diff --git a/src/main/java/io/github/randomcodespace/iq/analyzer/Analyzer.java b/src/main/java/io/github/randomcodespace/iq/analyzer/Analyzer.java
index 2093b74a..8b1430e8 100644
--- a/src/main/java/io/github/randomcodespace/iq/analyzer/Analyzer.java
+++ b/src/main/java/io/github/randomcodespace/iq/analyzer/Analyzer.java
@@ -61,6 +61,10 @@
  */
 @Service
 public class Analyzer {
+    private static final String PROP_FRAMEWORK = "framework";
+    private static final String PROP_ROOT = "root";
+    private static final String PROP_SERVICE = "service";
+
 
     private static final Logger log = LoggerFactory.getLogger(Analyzer.class);
 
@@ -335,7 +339,7 @@ private AnalysisResult runWithCache(Path root, Integer parallelism, AnalysisCach
         // 5b. Detect service boundaries and create SERVICE nodes
         report.accept("Detecting service boundaries...");
         var serviceDetector = new ServiceDetector();
-        String projectDirName = root.getFileName() != null ? root.getFileName().toString() : "root";
+        String projectDirName = root.getFileName() != null ? root.getFileName().toString() : PROP_ROOT;
         var serviceResult = serviceDetector.detect(allNodes, builder.getEdges(), projectDirName, root);
         if (!serviceResult.serviceNodes().isEmpty()) {
             serviceResult.serviceNodes().forEach(n -> n.setProvenance(builder.getProvenance()));
@@ -348,7 +352,7 @@ private AnalysisResult runWithCache(Path root, Integer parallelism, AnalysisCach
         String serviceName = config.getServiceName();
         if (serviceName != null && !serviceName.isBlank()) {
             for (CodeNode node : allNodes) {
-                node.getProperties().put("service", serviceName);
+                node.getProperties().put(PROP_SERVICE, serviceName);
             }
         }
 
@@ -381,7 +385,7 @@ private AnalysisResult runWithCache(Path root, Integer parallelism, AnalysisCach
         // 7b. Compute framework breakdown from node properties
         Map<String, Integer> frameworkBreakdown = new HashMap<>();
         for (CodeNode node : allNodes) {
-            Object fw = node.getProperties().get("framework");
+            Object fw = node.getProperties().get(PROP_FRAMEWORK);
             if (fw != null && !fw.toString().isEmpty()) {
                 frameworkBreakdown.merge(fw.toString(), 1, Integer::sum);
             }
@@ -611,13 +615,13 @@ private AnalysisResult runBatchedWithCache(Path root, Integer parallelism, int b
                         String svcName = config.getServiceName();
                         if (svcName != null && !svcName.isBlank()) {
                             for (CodeNode node : result.nodes()) {
-                                node.getProperties().put("service", svcName);
+                                node.getProperties().put(PROP_SERVICE, svcName);
                             }
                         }
                         // Track breakdowns
                         for (CodeNode node : result.nodes()) {
                             nodeBreakdown.merge(node.getKind().getValue(), 1, Integer::sum);
-                            Object fw = node.getProperties().get("framework");
+                            Object fw = node.getProperties().get(PROP_FRAMEWORK);
                             if (fw != null && !fw.toString().isEmpty()) {
                                 frameworkBreakdown.merge(fw.toString(), 1, Integer::sum);
                             }
@@ -971,12 +975,12 @@ private int[] processSmartBatch(
                 String svcName = config.getServiceName();
                 if (svcName != null && !svcName.isBlank()) {
                     for (CodeNode node : result.nodes()) {
-                        node.getProperties().put("service", svcName);
+                        node.getProperties().put(PROP_SERVICE, svcName);
                     }
                 }
                 for (CodeNode node : result.nodes()) {
                     nodeBreakdown.merge(node.getKind().getValue(), 1, Integer::sum);
-                    Object fw = node.getProperties().get("framework");
+                    Object fw = node.getProperties().get(PROP_FRAMEWORK);
                     if (fw != null && !fw.toString().isEmpty()) {
                         frameworkBreakdown.merge(fw.toString(), 1, Integer::sum);
                     }
@@ -1001,7 +1005,7 @@ private int[] processSmartBatch(
      * Partition discovered files into modules based on build-file boundary markers.
      * <p>
      * Files are assigned to the deepest module directory that contains them.
-     * Files with no matching module are placed in a {@code "root"} partition.
+     * Files with no matching module are placed in a {@code PROP_ROOT} partition.
      * The returned map is a {@link TreeMap} for deterministic iteration.
      *
      * @param root  absolute repository root (used only for logging)
@@ -1021,7 +1025,7 @@ Map<String, List<DiscoveredFile>> detectModules(Path root, List<DiscoveredFile>
         // If no module boundaries found, treat everything as root
         if (moduleDirs.isEmpty()) {
             Map<String, List<DiscoveredFile>> single = new TreeMap<>();
-            single.put("root", new ArrayList<>(files));
+            single.put(PROP_ROOT, new ArrayList<>(files));
             return single;
         }
 
@@ -1045,7 +1049,7 @@ Map<String, List<DiscoveredFile>> detectModules(Path root, List<DiscoveredFile>
                 }
             }
 
-            String key = bestModule != null ? bestModule : "root";
+            String key = bestModule != null ? bestModule : PROP_ROOT;
             result.computeIfAbsent(key, k -> new ArrayList<>()).add(file);
         }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/analyzer/ConfigScanner.java b/src/main/java/io/github/randomcodespace/iq/analyzer/ConfigScanner.java
index 12fbd486..9570a8d5 100644
--- a/src/main/java/io/github/randomcodespace/iq/analyzer/ConfigScanner.java
+++ b/src/main/java/io/github/randomcodespace/iq/analyzer/ConfigScanner.java
@@ -34,6 +34,22 @@
  */
 @Component
 public class ConfigScanner {
+    private static final String PROP_DEPENDENCY = "dependency";
+    private static final String PROP_DETECTION = "detection";
+    private static final String PROP_ELASTICSEARCH = "elasticsearch";
+    private static final String PROP_H2 = "h2";
+    private static final String PROP_KAFKA = "kafka";
+    private static final String PROP_MARIADB = "mariadb";
+    private static final String PROP_MONGO = "mongo";
+    private static final String PROP_MONGODB = "mongodb";
+    private static final String PROP_MYSQL = "mysql";
+    private static final String PROP_POM_XML = "pom.xml";
+    private static final String PROP_POSTGRESQL = "postgresql";
+    private static final String PROP_RABBITMQ = "rabbitmq";
+    private static final String PROP_REDIS = "redis";
+    private static final String PROP_SOURCE = "source";
+    private static final String PROP_SQL = "sql";
+
 
     private static final Logger log = LoggerFactory.getLogger(ConfigScanner.class);
 
@@ -152,7 +168,7 @@ private void processSpringFlatMap(Map<String, String> flat, InfrastructureRegist
                     "spring.datasource",
                     dbType,
                     dsUrl,
-                    Map.of("source", "spring.datasource.url")));
+                    Map.of(PROP_SOURCE, "spring.datasource.url")));
         }
 
         // Kafka bootstrap-servers
@@ -164,9 +180,9 @@ private void processSpringFlatMap(Map<String, String> flat, InfrastructureRegist
                     "topic:spring.kafka",
                     InfraEndpoint.Kind.TOPIC,
                     "spring.kafka",
-                    "kafka",
+                    PROP_KAFKA,
                     kafkaServers,
-                    Map.of("source", "spring.kafka.bootstrap-servers")));
+                    Map.of(PROP_SOURCE, "spring.kafka.bootstrap-servers")));
         }
 
         // Redis (spring.data.redis or spring.redis)
@@ -182,9 +198,9 @@ private void processSpringFlatMap(Map<String, String> flat, InfrastructureRegist
                     "cache:spring.redis",
                     InfraEndpoint.Kind.CACHE,
                     "spring.redis",
-                    "redis",
+                    PROP_REDIS,
                     "redis://" + redisHost + ":" + redisPort,
-                    Map.of("source", "spring.redis.host")));
+                    Map.of(PROP_SOURCE, "spring.redis.host")));
         }
 
         // RabbitMQ
@@ -195,9 +211,9 @@ private void processSpringFlatMap(Map<String, String> flat, InfrastructureRegist
                     "queue:spring.rabbitmq",
                     InfraEndpoint.Kind.QUEUE,
                     "spring.rabbitmq",
-                    "rabbitmq",
+                    PROP_RABBITMQ,
                     "amqp://" + rabbitHost + ":" + rabbitPort,
-                    Map.of("source", "spring.rabbitmq.host")));
+                    Map.of(PROP_SOURCE, "spring.rabbitmq.host")));
         }
     }
 
@@ -265,36 +281,36 @@ private void detectDockerInfra(String svcName, String image, String ports,
 
         Map<String, String> props = new TreeMap<>();
         props.put("image", image);
-        props.put("source", "docker-compose");
+        props.put(PROP_SOURCE, "docker-compose");
         if (ports != null) props.put("ports", ports);
 
         if (imageBase.contains("postgres")) {
             registry.register(new InfraEndpoint("db:compose:" + svcName,
-                    InfraEndpoint.Kind.DATABASE, svcName, "postgresql", null, props));
-        } else if (imageBase.contains("mariadb")) {
+                    InfraEndpoint.Kind.DATABASE, svcName, PROP_POSTGRESQL, null, props));
+        } else if (imageBase.contains(PROP_MARIADB)) {
             registry.register(new InfraEndpoint("db:compose:" + svcName,
-                    InfraEndpoint.Kind.DATABASE, svcName, "mariadb", null, props));
-        } else if (imageBase.contains("mysql")) {
+                    InfraEndpoint.Kind.DATABASE, svcName, PROP_MARIADB, null, props));
+        } else if (imageBase.contains(PROP_MYSQL)) {
             registry.register(new InfraEndpoint("db:compose:" + svcName,
-                    InfraEndpoint.Kind.DATABASE, svcName, "mysql", null, props));
-        } else if (imageBase.contains("mongo")) {
+                    InfraEndpoint.Kind.DATABASE, svcName, PROP_MYSQL, null, props));
+        } else if (imageBase.contains(PROP_MONGO)) {
             registry.register(new InfraEndpoint("db:compose:" + svcName,
-                    InfraEndpoint.Kind.DATABASE, svcName, "mongodb", null, props));
-        } else if (imageBase.contains("redis")) {
+                    InfraEndpoint.Kind.DATABASE, svcName, PROP_MONGODB, null, props));
+        } else if (imageBase.contains(PROP_REDIS)) {
             registry.register(new InfraEndpoint("cache:compose:" + svcName,
-                    InfraEndpoint.Kind.CACHE, svcName, "redis", null, props));
-        } else if (imageBase.contains("kafka") || imageBase.contains("cp-kafka")) {
+                    InfraEndpoint.Kind.CACHE, svcName, PROP_REDIS, null, props));
+        } else if (imageBase.contains(PROP_KAFKA) || imageBase.contains("cp-kafka")) {
             registry.register(new InfraEndpoint("topic:compose:" + svcName,
-                    InfraEndpoint.Kind.TOPIC, svcName, "kafka", null, props));
-        } else if (imageBase.contains("rabbitmq")) {
+                    InfraEndpoint.Kind.TOPIC, svcName, PROP_KAFKA, null, props));
+        } else if (imageBase.contains(PROP_RABBITMQ)) {
             registry.register(new InfraEndpoint("queue:compose:" + svcName,
-                    InfraEndpoint.Kind.QUEUE, svcName, "rabbitmq", null, props));
+                    InfraEndpoint.Kind.QUEUE, svcName, PROP_RABBITMQ, null, props));
         } else if (imageBase.contains("opensearch")) {
             registry.register(new InfraEndpoint("db:compose:" + svcName,
                     InfraEndpoint.Kind.DATABASE, svcName, "opensearch", null, props));
-        } else if (imageBase.contains("elasticsearch")) {
+        } else if (imageBase.contains(PROP_ELASTICSEARCH)) {
             registry.register(new InfraEndpoint("db:compose:" + svcName,
-                    InfraEndpoint.Kind.DATABASE, svcName, "elasticsearch", null, props));
+                    InfraEndpoint.Kind.DATABASE, svcName, PROP_ELASTICSEARCH, null, props));
         } else if (imageBase.contains("cassandra")) {
             registry.register(new InfraEndpoint("db:compose:" + svcName,
                     InfraEndpoint.Kind.DATABASE, svcName, "cassandra", null, props));
@@ -360,7 +376,7 @@ private void processEnvVars(Map<String, String> env, InfrastructureRegistry regi
             if (!registry.getDatabases().containsKey(id)) {
                 registry.register(new InfraEndpoint(id, InfraEndpoint.Kind.DATABASE,
                         "database_url", detectDatabaseTypeFromUrl(dbUrl), dbUrl,
-                        Map.of("source", ".env")));
+                        Map.of(PROP_SOURCE, ".env")));
             }
         } else {
             // DB_HOST fallback
@@ -370,8 +386,8 @@ private void processEnvVars(Map<String, String> env, InfrastructureRegistry regi
                 String id = "db:env:db_host";
                 if (!registry.getDatabases().containsKey(id)) {
                     registry.register(new InfraEndpoint(id, InfraEndpoint.Kind.DATABASE,
-                            "database", "postgresql", dbHost + ":" + dbPort,
-                            Map.of("source", ".env")));
+                            "database", PROP_POSTGRESQL, dbHost + ":" + dbPort,
+                            Map.of(PROP_SOURCE, ".env")));
                 }
             }
         }
@@ -382,7 +398,7 @@ private void processEnvVars(Map<String, String> env, InfrastructureRegistry regi
             String id = "cache:env:redis_url";
             if (!registry.getCaches().containsKey(id)) {
                 registry.register(new InfraEndpoint(id, InfraEndpoint.Kind.CACHE,
-                        "redis", "redis", redisUrl, Map.of("source", ".env")));
+                        PROP_REDIS, PROP_REDIS, redisUrl, Map.of(PROP_SOURCE, ".env")));
             }
         } else {
             String redisHost = env.get("REDIS_HOST");
@@ -391,8 +407,8 @@ private void processEnvVars(Map<String, String> env, InfrastructureRegistry regi
                 String id = "cache:env:redis_host";
                 if (!registry.getCaches().containsKey(id)) {
                     registry.register(new InfraEndpoint(id, InfraEndpoint.Kind.CACHE,
-                            "redis", "redis", "redis://" + redisHost + ":" + redisPort,
-                            Map.of("source", ".env")));
+                            PROP_REDIS, PROP_REDIS, "redis://" + redisHost + ":" + redisPort,
+                            Map.of(PROP_SOURCE, ".env")));
                 }
             }
         }
@@ -406,7 +422,7 @@ private void processEnvVars(Map<String, String> env, InfrastructureRegistry regi
             String id = "topic:env:kafka_brokers";
             if (!registry.getTopics().containsKey(id)) {
                 registry.register(new InfraEndpoint(id, InfraEndpoint.Kind.TOPIC,
-                        "kafka", "kafka", kafkaBrokers, Map.of("source", ".env")));
+                        PROP_KAFKA, PROP_KAFKA, kafkaBrokers, Map.of(PROP_SOURCE, ".env")));
             }
         }
     }
@@ -416,7 +432,7 @@ private void processEnvVars(Map<String, String> env, InfrastructureRegistry regi
     // -------------------------------------------------------------------------
 
     private void scanBuildFiles(Path root, InfrastructureRegistry registry) {
-        Path pomXml = root.resolve("pom.xml");
+        Path pomXml = root.resolve(PROP_POM_XML);
         if (Files.isRegularFile(pomXml)) {
             parsePomXml(pomXml, registry);
         }
@@ -428,26 +444,26 @@ private void parsePomXml(Path file, InfrastructureRegistry registry) {
             Set<String> artifactIds = extractPomArtifactIds(content);
 
             boolean hasJpa      = artifactIds.stream().anyMatch(a -> a.contains("jpa") || a.contains("hibernate") || a.contains("jdbc"));
-            boolean hasPostgres = artifactIds.contains("postgresql");
+            boolean hasPostgres = artifactIds.contains(PROP_POSTGRESQL);
             boolean hasMysql    = artifactIds.stream().anyMatch(a -> a.contains("mysql-connector"));
-            boolean hasH2       = artifactIds.contains("h2");
-            boolean hasMongo    = artifactIds.stream().anyMatch(a -> a.contains("mongo"));
-            boolean hasKafka    = artifactIds.stream().anyMatch(a -> a.contains("kafka"));
-            boolean hasRedis    = artifactIds.stream().anyMatch(a -> a.contains("redis") || a.equals("lettuce-core") || a.equals("jedis"));
-            boolean hasRabbit   = artifactIds.stream().anyMatch(a -> a.contains("amqp") || a.contains("rabbitmq"));
-            boolean hasElastic  = artifactIds.stream().anyMatch(a -> a.contains("elasticsearch"));
+            boolean hasH2       = artifactIds.contains(PROP_H2);
+            boolean hasMongo    = artifactIds.stream().anyMatch(a -> a.contains(PROP_MONGO));
+            boolean hasKafka    = artifactIds.stream().anyMatch(a -> a.contains(PROP_KAFKA));
+            boolean hasRedis    = artifactIds.stream().anyMatch(a -> a.contains(PROP_REDIS) || a.equals("lettuce-core") || a.equals("jedis"));
+            boolean hasRabbit   = artifactIds.stream().anyMatch(a -> a.contains("amqp") || a.contains(PROP_RABBITMQ));
+            boolean hasElastic  = artifactIds.stream().anyMatch(a -> a.contains(PROP_ELASTICSEARCH));
 
             if (hasJpa || hasPostgres || hasMysql || hasH2 || hasMongo) {
-                String dbType = hasPostgres ? "postgresql"
-                        : hasMysql ? "mysql"
-                        : hasMongo ? "mongodb"
-                        : hasH2    ? "h2"
-                        : "sql";
+                String dbType = hasPostgres ? PROP_POSTGRESQL
+                        : hasMysql ? PROP_MYSQL
+                        : hasMongo ? PROP_MONGODB
+                        : hasH2    ? PROP_H2
+                        : PROP_SQL;
                 String id = "db:pom:" + dbType;
                 if (!registry.getDatabases().containsKey(id)) {
                     registry.register(new InfraEndpoint(id, InfraEndpoint.Kind.DATABASE,
                             dbType, dbType, null,
-                            Map.of("source", "pom.xml", "detection", "dependency")));
+                            Map.of(PROP_SOURCE, PROP_POM_XML, PROP_DETECTION, PROP_DEPENDENCY)));
                 }
             }
 
@@ -455,8 +471,8 @@ private void parsePomXml(Path file, InfrastructureRegistry registry) {
                 String id = "topic:pom:kafka";
                 if (!registry.getTopics().containsKey(id)) {
                     registry.register(new InfraEndpoint(id, InfraEndpoint.Kind.TOPIC,
-                            "kafka", "kafka", null,
-                            Map.of("source", "pom.xml", "detection", "dependency")));
+                            PROP_KAFKA, PROP_KAFKA, null,
+                            Map.of(PROP_SOURCE, PROP_POM_XML, PROP_DETECTION, PROP_DEPENDENCY)));
                 }
             }
 
@@ -464,8 +480,8 @@ private void parsePomXml(Path file, InfrastructureRegistry registry) {
                 String id = "cache:pom:redis";
                 if (!registry.getCaches().containsKey(id)) {
                     registry.register(new InfraEndpoint(id, InfraEndpoint.Kind.CACHE,
-                            "redis", "redis", null,
-                            Map.of("source", "pom.xml", "detection", "dependency")));
+                            PROP_REDIS, PROP_REDIS, null,
+                            Map.of(PROP_SOURCE, PROP_POM_XML, PROP_DETECTION, PROP_DEPENDENCY)));
                 }
             }
 
@@ -473,8 +489,8 @@ private void parsePomXml(Path file, InfrastructureRegistry registry) {
                 String id = "queue:pom:rabbitmq";
                 if (!registry.getQueues().containsKey(id)) {
                     registry.register(new InfraEndpoint(id, InfraEndpoint.Kind.QUEUE,
-                            "rabbitmq", "rabbitmq", null,
-                            Map.of("source", "pom.xml", "detection", "dependency")));
+                            PROP_RABBITMQ, PROP_RABBITMQ, null,
+                            Map.of(PROP_SOURCE, PROP_POM_XML, PROP_DETECTION, PROP_DEPENDENCY)));
                 }
             }
 
@@ -482,8 +498,8 @@ private void parsePomXml(Path file, InfrastructureRegistry registry) {
                 String id = "db:pom:elasticsearch";
                 if (!registry.getDatabases().containsKey(id)) {
                     registry.register(new InfraEndpoint(id, InfraEndpoint.Kind.DATABASE,
-                            "elasticsearch", "elasticsearch", null,
-                            Map.of("source", "pom.xml", "detection", "dependency")));
+                            PROP_ELASTICSEARCH, PROP_ELASTICSEARCH, null,
+                            Map.of(PROP_SOURCE, PROP_POM_XML, PROP_DETECTION, PROP_DEPENDENCY)));
                 }
             }
         } catch (Exception e) {
@@ -505,17 +521,17 @@ private Set<String> extractPomArtifactIds(String content) {
     // -------------------------------------------------------------------------
 
     private String detectDatabaseTypeFromUrl(String url) {
-        if (url == null) return "sql";
+        if (url == null) return PROP_SQL;
         String lower = url.toLowerCase();
-        if (lower.contains("postgresql") || lower.contains("postgres")) return "postgresql";
-        if (lower.contains("mysql"))      return "mysql";
-        if (lower.contains("mariadb"))    return "mariadb";
+        if (lower.contains(PROP_POSTGRESQL) || lower.contains("postgres")) return PROP_POSTGRESQL;
+        if (lower.contains(PROP_MYSQL))      return PROP_MYSQL;
+        if (lower.contains(PROP_MARIADB))    return PROP_MARIADB;
         if (lower.contains("oracle"))     return "oracle";
         if (lower.contains("sqlserver") || lower.contains("mssql")) return "sqlserver";
-        if (lower.contains("h2"))         return "h2";
+        if (lower.contains(PROP_H2))         return PROP_H2;
         if (lower.contains("sqlite"))     return "sqlite";
-        if (lower.contains("mongodb") || lower.contains("mongo")) return "mongodb";
-        return "sql";
+        if (lower.contains(PROP_MONGODB) || lower.contains(PROP_MONGO)) return PROP_MONGODB;
+        return PROP_SQL;
     }
 
     private static String coalesce(String... values) {
diff --git a/src/main/java/io/github/randomcodespace/iq/analyzer/LayerClassifier.java b/src/main/java/io/github/randomcodespace/iq/analyzer/LayerClassifier.java
index 740498cc..3f6a4c39 100644
--- a/src/main/java/io/github/randomcodespace/iq/analyzer/LayerClassifier.java
+++ b/src/main/java/io/github/randomcodespace/iq/analyzer/LayerClassifier.java
@@ -17,6 +17,10 @@
  */
 @Service
 public class LayerClassifier {
+    private static final String PROP_BACKEND = "backend";
+    private static final String PROP_FRONTEND = "frontend";
+    private static final String PROP_UNKNOWN = "unknown";
+
 
     private static final Set<NodeKind> FRONTEND_NODE_KINDS = Set.of(
             NodeKind.COMPONENT, NodeKind.HOOK
@@ -67,7 +71,7 @@ public class LayerClassifier {
             "asp.net", "koa", "hapi", "fastify"
     );
 
-    // -- Fallback path heuristics (applied only to "unknown" nodes) --
+    // -- Fallback path heuristics (applied only to PROP_UNKNOWN nodes) --
 
     private static final Pattern BACKEND_PACKAGE_PATH_RE = Pattern.compile(
             "(?:^|/|\\.)(?:controller|controllers|api|web|rest|resource|resources|"
@@ -103,8 +107,8 @@ public void classify(List<CodeNode> nodes) {
      */
     String classifyOne(CodeNode node) {
         // 1. Node kind rules
-        if (FRONTEND_NODE_KINDS.contains(node.getKind())) return "frontend";
-        if (BACKEND_NODE_KINDS.contains(node.getKind())) return "backend";
+        if (FRONTEND_NODE_KINDS.contains(node.getKind())) return PROP_FRONTEND;
+        if (BACKEND_NODE_KINDS.contains(node.getKind())) return PROP_BACKEND;
         if (INFRA_NODE_KINDS.contains(node.getKind())) return "infra";
 
         // 2. Language rules
@@ -115,21 +119,21 @@ String classifyOne(CodeNode node) {
 
         // 3. File path rules
         String filePath = node.getFilePath() != null ? node.getFilePath() : "";
-        if (FRONTEND_EXT_RE.matcher(filePath).find()) return "frontend";
-        if (FRONTEND_PATH_RE.matcher(filePath).find()) return "frontend";
-        if (BACKEND_PATH_RE.matcher(filePath).find()) return "backend";
+        if (FRONTEND_EXT_RE.matcher(filePath).find()) return PROP_FRONTEND;
+        if (FRONTEND_PATH_RE.matcher(filePath).find()) return PROP_FRONTEND;
+        if (BACKEND_PATH_RE.matcher(filePath).find()) return PROP_BACKEND;
 
         // 4. Framework rules
         Object fw = node.getProperties().get("framework");
         if (fw instanceof String fwStr) {
-            if (FRONTEND_FRAMEWORKS.contains(fwStr)) return "frontend";
-            if (BACKEND_FRAMEWORKS.contains(fwStr)) return "backend";
+            if (FRONTEND_FRAMEWORKS.contains(fwStr)) return PROP_FRONTEND;
+            if (BACKEND_FRAMEWORKS.contains(fwStr)) return PROP_BACKEND;
         }
 
         // 5. Shared node kinds
         if (SHARED_NODE_KINDS.contains(node.getKind())) return "shared";
 
-        // 6. Fallback: package/path heuristics for remaining "unknown" nodes
+        // 6. Fallback: package/path heuristics for remaining PROP_UNKNOWN nodes
         return classifyByPathFallback(node);
     }
 
@@ -145,10 +149,10 @@ private String classifyByPathFallback(CodeNode node) {
         String combined = filePath + "|" + nodeId;
 
         // Check frontend path patterns first (components, views, pages, etc.)
-        if (FRONTEND_PACKAGE_PATH_RE.matcher(combined).find()) return "frontend";
+        if (FRONTEND_PACKAGE_PATH_RE.matcher(combined).find()) return PROP_FRONTEND;
 
         // Check backend path patterns (controller, model, repository, service, etc.)
-        if (BACKEND_PACKAGE_PATH_RE.matcher(combined).find()) return "backend";
+        if (BACKEND_PACKAGE_PATH_RE.matcher(combined).find()) return PROP_BACKEND;
 
         // Check shared path patterns (config, util, common, etc.)
         if (SHARED_PACKAGE_PATH_RE.matcher(combined).find()) return "shared";
@@ -158,7 +162,7 @@ private String classifyByPathFallback(CodeNode node) {
             return classifyJavaByPath(filePath);
         }
 
-        return "unknown";
+        return PROP_UNKNOWN;
     }
 
     /**
@@ -168,8 +172,8 @@ private String classifyByPathFallback(CodeNode node) {
     private String classifyJavaByPath(String filePath) {
         // Files in src/main/java or src/main/kotlin are virtually always backend
         if (filePath.contains("src/main/java/") || filePath.contains("src/main/kotlin/")) {
-            return "backend";
+            return PROP_BACKEND;
         }
-        return "unknown";
+        return PROP_UNKNOWN;
     }
 }
diff --git a/src/main/java/io/github/randomcodespace/iq/analyzer/ServiceDetector.java b/src/main/java/io/github/randomcodespace/iq/analyzer/ServiceDetector.java
index 0e8a614c..046c9957 100644
--- a/src/main/java/io/github/randomcodespace/iq/analyzer/ServiceDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/analyzer/ServiceDetector.java
@@ -40,6 +40,16 @@
  * </ul>
  */
 public class ServiceDetector {
+    private static final String PROP_DJANGO = "django";
+    private static final String PROP_DOCKER = "docker";
+    private static final String PROP_DOTNET = "dotnet";
+    private static final String PROP_GRADLE = "gradle";
+    private static final String PROP_HASKELL = "haskell";
+    private static final String PROP_PYPROJECT_TOML = "pyproject.toml";
+    private static final String PROP_PYTHON = "python";
+    private static final String PROP_RUBY = "ruby";
+    private static final String PROP_SETUP_PY = "setup.py";
+
 
     private static final Logger log = LoggerFactory.getLogger(ServiceDetector.class);
 
@@ -50,10 +60,10 @@ public class ServiceDetector {
     private static final Map<String, String> BUILD_FILES = Map.ofEntries(
             // Java/JVM
             Map.entry("pom.xml", "maven"),
-            Map.entry("build.gradle", "gradle"),
-            Map.entry("build.gradle.kts", "gradle"),
-            Map.entry("settings.gradle", "gradle"),
-            Map.entry("settings.gradle.kts", "gradle"),
+            Map.entry("build.gradle", PROP_GRADLE),
+            Map.entry("build.gradle.kts", PROP_GRADLE),
+            Map.entry("settings.gradle", PROP_GRADLE),
+            Map.entry("settings.gradle.kts", PROP_GRADLE),
             Map.entry("build.xml", "ant"),
             Map.entry("build.sbt", "sbt"),
             Map.entry("project.clj", "leiningen"),
@@ -66,18 +76,18 @@ public class ServiceDetector {
             // Rust
             Map.entry("Cargo.toml", "cargo"),
             // Python
-            Map.entry("pyproject.toml", "python"),
-            Map.entry("setup.py", "python"),
-            Map.entry("setup.cfg", "python"),
-            Map.entry("Pipfile", "python"),
-            Map.entry("requirements.txt", "python"),
-            Map.entry("manage.py", "django"),
+            Map.entry(PROP_PYPROJECT_TOML, PROP_PYTHON),
+            Map.entry(PROP_SETUP_PY, PROP_PYTHON),
+            Map.entry("setup.cfg", PROP_PYTHON),
+            Map.entry("Pipfile", PROP_PYTHON),
+            Map.entry("requirements.txt", PROP_PYTHON),
+            Map.entry("manage.py", PROP_DJANGO),
             // Ruby
-            Map.entry("Gemfile", "ruby"),
+            Map.entry("Gemfile", PROP_RUBY),
             // PHP
             Map.entry("composer.json", "php"),
             // .NET (csproj handled by suffix match below)
-            Map.entry("Directory.Build.props", "dotnet"),
+            Map.entry("Directory.Build.props", PROP_DOTNET),
             // Swift
             Map.entry("Package.swift", "swift"),
             // Elixir
@@ -86,7 +96,7 @@ public class ServiceDetector {
             Map.entry("pubspec.yaml", "dart"),
             // Scala (also build.sbt above)
             // Haskell
-            Map.entry("stack.yaml", "haskell"),
+            Map.entry("stack.yaml", PROP_HASKELL),
             // Zig
             Map.entry("build.zig", "zig"),
             // OCaml
@@ -102,11 +112,11 @@ public class ServiceDetector {
             Map.entry("turbo.json", "turbo"),
             Map.entry("rush.json", "rush"),
             // Docker (supplemental -- doesn't override other tools)
-            Map.entry("Dockerfile", "docker"),
-            Map.entry("docker-compose.yml", "docker"),
-            Map.entry("docker-compose.yaml", "docker"),
-            Map.entry("compose.yml", "docker"),
-            Map.entry("compose.yaml", "docker")
+            Map.entry("Dockerfile", PROP_DOCKER),
+            Map.entry("docker-compose.yml", PROP_DOCKER),
+            Map.entry("docker-compose.yaml", PROP_DOCKER),
+            Map.entry("compose.yml", PROP_DOCKER),
+            Map.entry("compose.yaml", PROP_DOCKER)
     );
 
     /** File extensions matched by suffix (not exact name). */
@@ -119,12 +129,12 @@ public class ServiceDetector {
 
     /** Build tools that are supplemental (don't override real build tools). */
     private static final java.util.Set<String> SUPPLEMENTAL_TOOLS = java.util.Set.of(
-            "docker", "nx", "lerna", "turbo", "rush"
+            PROP_DOCKER, "nx", "lerna", "turbo", "rush"
     );
 
     /** Python build files ranked by priority (first match wins for a directory). */
     private static final List<String> PYTHON_BUILD_FILES = List.of(
-            "pyproject.toml", "setup.py", "requirements.txt", "manage.py"
+            PROP_PYPROJECT_TOML, PROP_SETUP_PY, "requirements.txt", "manage.py"
     );
 
     /** Regex patterns for extracting names from build file contents. */
@@ -199,11 +209,11 @@ public ServiceDetectionResult detect(List<CodeNode> nodes, List<CodeEdge> edges,
             }
             if (fileName.endsWith(CSPROJ_EXTENSION) || fileName.endsWith(FSPROJ_EXTENSION)
                     || fileName.endsWith(VBPROJ_EXTENSION)) {
-                modules.putIfAbsent(dirPath, new ModuleInfo(dirPath, "dotnet", fileName));
+                modules.putIfAbsent(dirPath, new ModuleInfo(dirPath, PROP_DOTNET, fileName));
             } else if (fileName.endsWith(GEMSPEC_EXTENSION)) {
-                modules.putIfAbsent(dirPath, new ModuleInfo(dirPath, "ruby", fileName));
+                modules.putIfAbsent(dirPath, new ModuleInfo(dirPath, PROP_RUBY, fileName));
             } else if (fileName.endsWith(CABAL_EXTENSION)) {
-                modules.putIfAbsent(dirPath, new ModuleInfo(dirPath, "haskell", fileName));
+                modules.putIfAbsent(dirPath, new ModuleInfo(dirPath, PROP_HASKELL, fileName));
             } else if (fileName.endsWith(NIMBLE_EXTENSION)) {
                 modules.putIfAbsent(dirPath, new ModuleInfo(dirPath, "nim", fileName));
             }
@@ -356,11 +366,11 @@ public java.nio.file.FileVisitResult visitFile(Path file, java.nio.file.attribut
 
                     if (name.endsWith(CSPROJ_EXTENSION) || name.endsWith(FSPROJ_EXTENSION)
                             || name.endsWith(VBPROJ_EXTENSION)) {
-                        modules.putIfAbsent(relDir, new ModuleInfo(relDir, "dotnet", name));
+                        modules.putIfAbsent(relDir, new ModuleInfo(relDir, PROP_DOTNET, name));
                     } else if (name.endsWith(GEMSPEC_EXTENSION)) {
-                        modules.putIfAbsent(relDir, new ModuleInfo(relDir, "ruby", name));
+                        modules.putIfAbsent(relDir, new ModuleInfo(relDir, PROP_RUBY, name));
                     } else if (name.endsWith(CABAL_EXTENSION)) {
-                        modules.putIfAbsent(relDir, new ModuleInfo(relDir, "haskell", name));
+                        modules.putIfAbsent(relDir, new ModuleInfo(relDir, PROP_HASKELL, name));
                     } else if (name.endsWith(NIMBLE_EXTENSION)) {
                         modules.putIfAbsent(relDir, new ModuleInfo(relDir, "nim", name));
                     } else {
@@ -436,16 +446,16 @@ private String readNameFromBuildFile(Path projectRoot, String dir, ModuleInfo in
             String content = Files.readString(buildFile, StandardCharsets.UTF_8);
             return switch (info.buildTool()) {
                 case "maven" -> extractFromPom(content);
-                case "gradle" -> extractFromGradleSettings(content, info.buildFile());
+                case PROP_GRADLE -> extractFromGradleSettings(content, info.buildFile());
                 case "npm" -> extractFromPackageJson(content);
                 case "go" -> extractFromGoMod(content);
                 case "cargo" -> extractFromCargoToml(content);
-                case "python" -> extractFromPythonBuild(content, info.buildFile());
+                case PROP_PYTHON -> extractFromPythonBuild(content, info.buildFile());
                 case "sbt" -> extractWithPattern(content, SBT_NAME);
                 case "php" -> extractWithPattern(content, COMPOSER_NAME);
                 case "elixir" -> extractWithPattern(content, MIX_APP_NAME);
                 case "dart" -> extractWithPattern(content, PUBSPEC_NAME);
-                case "django" -> null;
+                case PROP_DJANGO -> null;
                 default -> null;
             };
         } catch (IOException e) {
diff --git a/src/main/java/io/github/randomcodespace/iq/analyzer/StructuredParser.java b/src/main/java/io/github/randomcodespace/iq/analyzer/StructuredParser.java
index c9a0cd49..5448c7ad 100644
--- a/src/main/java/io/github/randomcodespace/iq/analyzer/StructuredParser.java
+++ b/src/main/java/io/github/randomcodespace/iq/analyzer/StructuredParser.java
@@ -24,6 +24,9 @@
  */
 @Service
 public class StructuredParser {
+    private static final String PROP_DATA = "data";
+    private static final String PROP_TYPE = "type";
+
 
     private static final Logger log = LoggerFactory.getLogger(StructuredParser.class);
 
@@ -70,10 +73,10 @@ private Object parseYaml(String content) {
 
         Map<String, Object> result = new LinkedHashMap<>();
         if (docs.size() <= 1) {
-            result.put("type", "yaml");
-            result.put("data", docs.isEmpty() ? null : docs.getFirst());
+            result.put(PROP_TYPE, "yaml");
+            result.put(PROP_DATA, docs.isEmpty() ? null : docs.getFirst());
         } else {
-            result.put("type", "yaml_multi");
+            result.put(PROP_TYPE, "yaml_multi");
             result.put("documents", docs);
         }
         return result;
@@ -83,8 +86,8 @@ private Object parseYaml(String content) {
     private Object parseJson(String content) throws Exception {
         Object data = objectMapper.readValue(content, Object.class);
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("type", "json");
-        result.put("data", data);
+        result.put(PROP_TYPE, "json");
+        result.put(PROP_DATA, data);
         return result;
     }
 
@@ -107,7 +110,7 @@ private Object parseXml(String content, String filePath) throws Exception {
         var root = doc.getDocumentElement();
         // Return a simple map with root element info for structured detectors
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("type", "xml");
+        result.put(PROP_TYPE, "xml");
         result.put("file", filePath);
         result.put("rootElement", root.getTagName());
         result.put("rootNamespace", root.getNamespaceURI());
@@ -150,8 +153,8 @@ private Object parseToml(String content) {
             }
         }
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("type", "toml");
-        result.put("data", data);
+        result.put(PROP_TYPE, "toml");
+        result.put(PROP_DATA, data);
         return result;
     }
 
@@ -180,8 +183,8 @@ private Object parseIni(String content) {
             }
         }
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("type", "ini");
-        result.put("data", data);
+        result.put(PROP_TYPE, "ini");
+        result.put(PROP_DATA, data);
         return result;
     }
 
@@ -195,8 +198,8 @@ private Object parseProperties(String content) throws Exception {
             data.put(key, props.getProperty(key));
         }
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("type", "properties");
-        result.put("data", data);
+        result.put(PROP_TYPE, "properties");
+        result.put(PROP_DATA, data);
         return result;
     }
 }
diff --git a/src/main/java/io/github/randomcodespace/iq/cli/StatsCommand.java b/src/main/java/io/github/randomcodespace/iq/cli/StatsCommand.java
index 6576d8e3..933f2044 100644
--- a/src/main/java/io/github/randomcodespace/iq/cli/StatsCommand.java
+++ b/src/main/java/io/github/randomcodespace/iq/cli/StatsCommand.java
@@ -36,6 +36,15 @@
 @Command(name = "stats", mixinStandardHelpOptions = true,
         description = "Show rich statistics from analyzed graph")
 public class StatsCommand implements Callable<Integer> {
+    private static final String PROP_COUNT = "Count";
+    private static final String PROP_ARCHITECTURE = "architecture";
+    private static final String PROP_AUTH = "auth";
+    private static final String PROP_CONNECTIONS = "connections";
+    private static final String PROP_FRAMEWORKS = "frameworks";
+    private static final String PROP_GRAPH = "graph";
+    private static final String PROP_INFRA = "infra";
+    private static final String PROP_LANGUAGES = "languages";
+
 
     @Parameters(index = "0", defaultValue = ".", description = "Path to analyzed codebase")
     private Path path;
@@ -66,8 +75,8 @@ void setOut(PrintStream out) {
 
     private static final Set<String> VALID_FORMATS = Set.of("pretty", "yaml", "json", "markdown");
     private static final Set<String> VALID_CATEGORIES = Set.of(
-            "all", "graph", "languages", "frameworks", "infra",
-            "connections", "auth", "architecture");
+            "all", PROP_GRAPH, PROP_LANGUAGES, PROP_FRAMEWORKS, PROP_INFRA,
+            PROP_CONNECTIONS, PROP_AUTH, PROP_ARCHITECTURE);
 
     @Override
     public Integer call() {
@@ -136,18 +145,18 @@ int outputPretty(Map<String, Object> stats) {
         out.println();
 
         // Graph
-        if (stats.containsKey("graph")) {
+        if (stats.containsKey(PROP_GRAPH)) {
             @SuppressWarnings("unchecked")
-            Map<String, Object> graph = (Map<String, Object>) stats.get("graph");
+            Map<String, Object> graph = (Map<String, Object>) stats.get(PROP_GRAPH);
             out.println("  Graph:        " + nf.format(toLong(graph.get("nodes")))
                     + " nodes, " + nf.format(toLong(graph.get("edges")))
                     + " edges, " + nf.format(toLong(graph.get("files"))) + " files");
         }
 
         // Languages
-        if (stats.containsKey("languages")) {
+        if (stats.containsKey(PROP_LANGUAGES)) {
             @SuppressWarnings("unchecked")
-            Map<String, Object> languages = (Map<String, Object>) stats.get("languages");
+            Map<String, Object> languages = (Map<String, Object>) stats.get(PROP_LANGUAGES);
             if (!languages.isEmpty()) {
                 StringBuilder sb = new StringBuilder("  Languages:    ");
                 languages.entrySet().stream().limit(10).forEach(e ->
@@ -158,9 +167,9 @@ int outputPretty(Map<String, Object> stats) {
         }
 
         // Frameworks
-        if (stats.containsKey("frameworks")) {
+        if (stats.containsKey(PROP_FRAMEWORKS)) {
             @SuppressWarnings("unchecked")
-            Map<String, Object> frameworks = (Map<String, Object>) stats.get("frameworks");
+            Map<String, Object> frameworks = (Map<String, Object>) stats.get(PROP_FRAMEWORKS);
             if (!frameworks.isEmpty()) {
                 out.println();
                 StringBuilder sb = new StringBuilder("  Frameworks:   ");
@@ -174,7 +183,7 @@ int outputPretty(Map<String, Object> stats) {
         // Infrastructure
         if (stats.containsKey("infra")) {
             @SuppressWarnings("unchecked")
-            Map<String, Object> infra = (Map<String, Object>) stats.get("infra");
+            Map<String, Object> infra = (Map<String, Object>) stats.get(PROP_INFRA);
             boolean hasInfra = infra.values().stream()
                     .anyMatch(v -> v instanceof Map<?, ?> m && !m.isEmpty());
             if (hasInfra) {
@@ -187,9 +196,9 @@ int outputPretty(Map<String, Object> stats) {
         }
 
         // Connections
-        if (stats.containsKey("connections")) {
+        if (stats.containsKey(PROP_CONNECTIONS)) {
             @SuppressWarnings("unchecked")
-            Map<String, Object> conn = (Map<String, Object>) stats.get("connections");
+            Map<String, Object> conn = (Map<String, Object>) stats.get(PROP_CONNECTIONS);
             out.println();
             out.println("  Connections:");
 
@@ -220,7 +229,7 @@ int outputPretty(Map<String, Object> stats) {
         // Auth
         if (stats.containsKey("auth")) {
             @SuppressWarnings("unchecked")
-            Map<String, Object> auth = (Map<String, Object>) stats.get("auth");
+            Map<String, Object> auth = (Map<String, Object>) stats.get(PROP_AUTH);
             if (!auth.isEmpty()) {
                 out.println();
                 out.println("  Auth:");
@@ -230,9 +239,9 @@ int outputPretty(Map<String, Object> stats) {
         }
 
         // Architecture
-        if (stats.containsKey("architecture")) {
+        if (stats.containsKey(PROP_ARCHITECTURE)) {
             @SuppressWarnings("unchecked")
-            Map<String, Object> arch = (Map<String, Object>) stats.get("architecture");
+            Map<String, Object> arch = (Map<String, Object>) stats.get(PROP_ARCHITECTURE);
             if (!arch.isEmpty()) {
                 out.println();
                 out.println("  Architecture:");
@@ -274,7 +283,7 @@ int outputMarkdown(Map<String, Object> stats) {
 
         if (stats.containsKey("graph")) {
             @SuppressWarnings("unchecked")
-            Map<String, Object> graph = (Map<String, Object>) stats.get("graph");
+            Map<String, Object> graph = (Map<String, Object>) stats.get(PROP_GRAPH);
             out.println("## Graph");
             out.println();
             out.println("| Metric | Count |");
@@ -283,12 +292,12 @@ int outputMarkdown(Map<String, Object> stats) {
             out.println();
         }
 
-        printMarkdownSection(nf, stats, "languages", "Languages", "Language", "Count");
-        printMarkdownSection(nf, stats, "frameworks", "Frameworks", "Framework", "Count");
+        printMarkdownSection(nf, stats, PROP_LANGUAGES, "Languages", "Language", PROP_COUNT);
+        printMarkdownSection(nf, stats, PROP_FRAMEWORKS, "Frameworks", "Framework", PROP_COUNT);
 
-        if (stats.containsKey("infra")) {
+        if (stats.containsKey(PROP_INFRA)) {
             @SuppressWarnings("unchecked")
-            Map<String, Object> infra = (Map<String, Object>) stats.get("infra");
+            Map<String, Object> infra = (Map<String, Object>) stats.get(PROP_INFRA);
             out.println("## Infrastructure");
             out.println();
             for (Map.Entry<String, Object> section : infra.entrySet()) {
@@ -305,9 +314,9 @@ int outputMarkdown(Map<String, Object> stats) {
             }
         }
 
-        if (stats.containsKey("connections")) {
+        if (stats.containsKey(PROP_CONNECTIONS)) {
             @SuppressWarnings("unchecked")
-            Map<String, Object> conn = (Map<String, Object>) stats.get("connections");
+            Map<String, Object> conn = (Map<String, Object>) stats.get(PROP_CONNECTIONS);
             out.println("## Connections");
             out.println();
             out.println("| Type | Count |");
@@ -330,8 +339,8 @@ int outputMarkdown(Map<String, Object> stats) {
             out.println();
         }
 
-        printMarkdownSection(nf, stats, "auth", "Auth", "Type", "Count");
-        printMarkdownSection(nf, stats, "architecture", "Architecture", "Kind", "Count");
+        printMarkdownSection(nf, stats, PROP_AUTH, "Auth", "Type", PROP_COUNT);
+        printMarkdownSection(nf, stats, PROP_ARCHITECTURE, "Architecture", "Kind", PROP_COUNT);
 
         return 0;
     }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/auth/CertificateAuthDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/auth/CertificateAuthDetector.java
index 69f302f4..5dd1616f 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/auth/CertificateAuthDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/auth/CertificateAuthDetector.java
@@ -25,39 +25,44 @@
 )
 @Component
 public class CertificateAuthDetector extends AbstractRegexDetector {
+    private static final String PROP_AZURE_AD = "azure_ad";
+    private static final String PROP_MTLS = "mtls";
+    private static final String PROP_TLS_CONFIG = "tls_config";
+    private static final String PROP_X509 = "x509";
+
 
     private record PatternDef(Pattern regex, String authType) {}
 
     private static final List<PatternDef> MTLS_PATTERNS = List.of(
-            new PatternDef(Pattern.compile("\\bssl_verify_client\\b"), "mtls"),
-            new PatternDef(Pattern.compile("\\brequestCert\\s*:\\s*true\\b"), "mtls"),
-            new PatternDef(Pattern.compile("\\bclientAuth\\s*=\\s*\"true\""), "mtls"),
-            new PatternDef(Pattern.compile("\\bX509AuthenticationFilter\\b"), "mtls"),
-            new PatternDef(Pattern.compile("\\bAddCertificateForwarding\\b"), "mtls")
+            new PatternDef(Pattern.compile("\\bssl_verify_client\\b"), PROP_MTLS),
+            new PatternDef(Pattern.compile("\\brequestCert\\s*:\\s*true\\b"), PROP_MTLS),
+            new PatternDef(Pattern.compile("\\bclientAuth\\s*=\\s*\"true\""), PROP_MTLS),
+            new PatternDef(Pattern.compile("\\bX509AuthenticationFilter\\b"), PROP_MTLS),
+            new PatternDef(Pattern.compile("\\bAddCertificateForwarding\\b"), PROP_MTLS)
     );
 
     private static final List<PatternDef> X509_PATTERNS = List.of(
-            new PatternDef(Pattern.compile("\\bX509AuthenticationFilter\\b"), "x509"),
-            new PatternDef(Pattern.compile("\\bCertificateAuthenticationDefaults\\b"), "x509"),
-            new PatternDef(Pattern.compile("\\.x509\\s*\\("), "x509")
+            new PatternDef(Pattern.compile("\\bX509AuthenticationFilter\\b"), PROP_X509),
+            new PatternDef(Pattern.compile("\\bCertificateAuthenticationDefaults\\b"), PROP_X509),
+            new PatternDef(Pattern.compile("\\.x509\\s*\\("), PROP_X509)
     );
 
     private static final List<PatternDef> TLS_CONFIG_PATTERNS = List.of(
-            new PatternDef(Pattern.compile("\\bjavax\\.net\\.ssl\\.keyStore\\b"), "tls_config"),
-            new PatternDef(Pattern.compile("\\bssl\\.SSLContext\\b"), "tls_config"),
-            new PatternDef(Pattern.compile("\\btls\\.createServer\\b"), "tls_config"),
-            new PatternDef(Pattern.compile("(?:cert|key|ca)\\s*[=:]\\s*(?:fs\\.readFileSync\\s*\\(|['\"][\\w/.\\\\-]+\\.(?:pem|crt|key|cert)['\"])"), "tls_config"),
-            new PatternDef(Pattern.compile("\\btrustStore\\b"), "tls_config")
+            new PatternDef(Pattern.compile("\\bjavax\\.net\\.ssl\\.keyStore\\b"), PROP_TLS_CONFIG),
+            new PatternDef(Pattern.compile("\\bssl\\.SSLContext\\b"), PROP_TLS_CONFIG),
+            new PatternDef(Pattern.compile("\\btls\\.createServer\\b"), PROP_TLS_CONFIG),
+            new PatternDef(Pattern.compile("(?:cert|key|ca)\\s*[=:]\\s*(?:fs\\.readFileSync\\s*\\(|['\"][\\w/.\\\\-]+\\.(?:pem|crt|key|cert)['\"])"), PROP_TLS_CONFIG),
+            new PatternDef(Pattern.compile("\\btrustStore\\b"), PROP_TLS_CONFIG)
     );
 
     private static final List<PatternDef> AZURE_AD_PATTERNS = List.of(
-            new PatternDef(Pattern.compile("\\bAzureAd\\b"), "azure_ad"),
-            new PatternDef(Pattern.compile("\\bAZURE_TENANT_ID\\b"), "azure_ad"),
-            new PatternDef(Pattern.compile("\\bAZURE_CLIENT_ID\\b"), "azure_ad"),
-            new PatternDef(Pattern.compile("\\bmsal\\b"), "azure_ad"),
-            new PatternDef(Pattern.compile("['\"]@azure/msal-browser['\"]"), "azure_ad"),
-            new PatternDef(Pattern.compile("\\bAddMicrosoftIdentityWebApi\\b"), "azure_ad"),
-            new PatternDef(Pattern.compile("\\bClientCertificateCredential\\b"), "azure_ad")
+            new PatternDef(Pattern.compile("\\bAzureAd\\b"), PROP_AZURE_AD),
+            new PatternDef(Pattern.compile("\\bAZURE_TENANT_ID\\b"), PROP_AZURE_AD),
+            new PatternDef(Pattern.compile("\\bAZURE_CLIENT_ID\\b"), PROP_AZURE_AD),
+            new PatternDef(Pattern.compile("\\bmsal\\b"), PROP_AZURE_AD),
+            new PatternDef(Pattern.compile("['\"]@azure/msal-browser['\"]"), PROP_AZURE_AD),
+            new PatternDef(Pattern.compile("\\bAddMicrosoftIdentityWebApi\\b"), PROP_AZURE_AD),
+            new PatternDef(Pattern.compile("\\bClientCertificateCredential\\b"), PROP_AZURE_AD)
     );
 
     private static final List<PatternDef> ALL_PATTERNS;
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/auth/SessionHeaderAuthDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/auth/SessionHeaderAuthDetector.java
index 9d57e597..6ffe5718 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/auth/SessionHeaderAuthDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/auth/SessionHeaderAuthDetector.java
@@ -25,35 +25,40 @@
 )
 @Component
 public class SessionHeaderAuthDetector extends AbstractRegexDetector {
+    private static final String PROP_API_KEY = "api_key";
+    private static final String PROP_CSRF = "csrf";
+    private static final String PROP_HEADER = "header";
+    private static final String PROP_SESSION = "session";
+
 
     private record PatternDef(Pattern regex, String authType, NodeKind nodeKind) {}
 
     private static final List<PatternDef> SESSION_PATTERNS = List.of(
-            new PatternDef(Pattern.compile("['\"]express-session['\"]"), "session", NodeKind.MIDDLEWARE),
-            new PatternDef(Pattern.compile("['\"]cookie-session['\"]"), "session", NodeKind.MIDDLEWARE),
-            new PatternDef(Pattern.compile("@SessionAttributes\\b"), "session", NodeKind.GUARD),
-            new PatternDef(Pattern.compile("\\bSessionMiddleware\\b"), "session", NodeKind.MIDDLEWARE),
-            new PatternDef(Pattern.compile("\\bHttpSession\\b"), "session", NodeKind.GUARD),
-            new PatternDef(Pattern.compile("\\bSESSION_ENGINE\\b"), "session", NodeKind.GUARD)
+            new PatternDef(Pattern.compile("['\"]express-session['\"]"), PROP_SESSION, NodeKind.MIDDLEWARE),
+            new PatternDef(Pattern.compile("['\"]cookie-session['\"]"), PROP_SESSION, NodeKind.MIDDLEWARE),
+            new PatternDef(Pattern.compile("@SessionAttributes\\b"), PROP_SESSION, NodeKind.GUARD),
+            new PatternDef(Pattern.compile("\\bSessionMiddleware\\b"), PROP_SESSION, NodeKind.MIDDLEWARE),
+            new PatternDef(Pattern.compile("\\bHttpSession\\b"), PROP_SESSION, NodeKind.GUARD),
+            new PatternDef(Pattern.compile("\\bSESSION_ENGINE\\b"), PROP_SESSION, NodeKind.GUARD)
     );
 
     private static final List<PatternDef> HEADER_PATTERNS = List.of(
-            new PatternDef(Pattern.compile("['\"]X-API-Key['\"]", Pattern.CASE_INSENSITIVE), "header", NodeKind.GUARD),
-            new PatternDef(Pattern.compile("(?:req|request|ctx)\\.headers?\\s*\\[\\s*['\"]authorization['\"]\\s*]", Pattern.CASE_INSENSITIVE), "header", NodeKind.GUARD),
-            new PatternDef(Pattern.compile("getHeader\\s*\\(\\s*['\"]Authorization['\"]", Pattern.CASE_INSENSITIVE), "header", NodeKind.GUARD)
+            new PatternDef(Pattern.compile("['\"]X-API-Key['\"]", Pattern.CASE_INSENSITIVE), PROP_HEADER, NodeKind.GUARD),
+            new PatternDef(Pattern.compile("(?:req|request|ctx)\\.headers?\\s*\\[\\s*['\"]authorization['\"]\\s*]", Pattern.CASE_INSENSITIVE), PROP_HEADER, NodeKind.GUARD),
+            new PatternDef(Pattern.compile("getHeader\\s*\\(\\s*['\"]Authorization['\"]", Pattern.CASE_INSENSITIVE), PROP_HEADER, NodeKind.GUARD)
     );
 
     private static final List<PatternDef> API_KEY_PATTERNS = List.of(
-            new PatternDef(Pattern.compile("(?:req|request)\\.headers?\\s*\\[\\s*['\"]x-api-key['\"]\\s*]", Pattern.CASE_INSENSITIVE), "api_key", NodeKind.GUARD),
-            new PatternDef(Pattern.compile("\\bapi[_-]?key\\s*[=:]\\s*", Pattern.CASE_INSENSITIVE), "api_key", NodeKind.GUARD),
-            new PatternDef(Pattern.compile("\\bvalidate_?api_?key\\b", Pattern.CASE_INSENSITIVE), "api_key", NodeKind.GUARD)
+            new PatternDef(Pattern.compile("(?:req|request)\\.headers?\\s*\\[\\s*['\"]x-api-key['\"]\\s*]", Pattern.CASE_INSENSITIVE), PROP_API_KEY, NodeKind.GUARD),
+            new PatternDef(Pattern.compile("\\bapi[_-]?key\\s*[=:]\\s*", Pattern.CASE_INSENSITIVE), PROP_API_KEY, NodeKind.GUARD),
+            new PatternDef(Pattern.compile("\\bvalidate_?api_?key\\b", Pattern.CASE_INSENSITIVE), PROP_API_KEY, NodeKind.GUARD)
     );
 
     private static final List<PatternDef> CSRF_PATTERNS = List.of(
-            new PatternDef(Pattern.compile("@csrf_protect\\b"), "csrf", NodeKind.GUARD),
-            new PatternDef(Pattern.compile("\\bcsrf_exempt\\b"), "csrf", NodeKind.GUARD),
-            new PatternDef(Pattern.compile("\\bCsrfViewMiddleware\\b"), "csrf", NodeKind.MIDDLEWARE),
-            new PatternDef(Pattern.compile("['\"]csurf['\"]"), "csrf", NodeKind.MIDDLEWARE)
+            new PatternDef(Pattern.compile("@csrf_protect\\b"), PROP_CSRF, NodeKind.GUARD),
+            new PatternDef(Pattern.compile("\\bcsrf_exempt\\b"), PROP_CSRF, NodeKind.GUARD),
+            new PatternDef(Pattern.compile("\\bCsrfViewMiddleware\\b"), PROP_CSRF, NodeKind.MIDDLEWARE),
+            new PatternDef(Pattern.compile("['\"]csurf['\"]"), PROP_CSRF, NodeKind.MIDDLEWARE)
     );
 
     private static final List<PatternDef> ALL_PATTERNS;
@@ -67,10 +72,10 @@ private record PatternDef(Pattern regex, String authType, NodeKind nodeKind) {}
     }
 
     private static final Map<String, String> ID_TAG = Map.of(
-            "session", "session",
-            "header", "header",
-            "api_key", "apikey",
-            "csrf", "csrf"
+            PROP_SESSION, PROP_SESSION,
+            PROP_HEADER, PROP_HEADER,
+            PROP_API_KEY, "apikey",
+            PROP_CSRF, PROP_CSRF
     );
 
     @Override
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/CloudFormationDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/CloudFormationDetector.java
index acacd236..8b49c7b4 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/CloudFormationDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/CloudFormationDetector.java
@@ -34,6 +34,8 @@
 )
 @Component
 public class CloudFormationDetector extends AbstractStructuredDetector {
+    private static final String PROP_TYPE = "Type";
+
 
     @Override
     public String getName() {
@@ -66,7 +68,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 Map<String, Object> resource = asMap(entry.getValue());
                 if (resource.isEmpty()) continue;
 
-                String resourceType = getStringOrDefault(resource, "Type", "unknown");
+                String resourceType = getStringOrDefault(resource, PROP_TYPE, "unknown");
                 String nodeId = "cfn:" + fp + ":resource:" + logicalId;
 
                 Map<String, Object> props = new HashMap<>();
@@ -107,7 +109,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 Map<String, Object> paramDef = asMap(entry.getValue());
                 if (paramDef.isEmpty()) continue;
 
-                String paramType = getStringOrDefault(paramDef, "Type", "String");
+                String paramType = getStringOrDefault(paramDef, PROP_TYPE, "String");
                 Map<String, Object> props = new HashMap<>();
                 props.put("param_type", paramType);
                 props.put("cfn_type", "parameter");
@@ -179,7 +181,7 @@ private boolean isCfnTemplate(Map<String, Object> data) {
         Map<String, Object> resources = getMap(data, "Resources");
         for (Object val : resources.values()) {
             Map<String, Object> resource = asMap(val);
-            String rtype = getString(resource, "Type");
+            String rtype = getString(resource, PROP_TYPE);
             if (rtype != null && rtype.startsWith("AWS::")) return true;
         }
         return false;
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/GitLabCiDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/GitLabCiDetector.java
index 7a5598b3..d040f9a6 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/GitLabCiDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/GitLabCiDetector.java
@@ -33,10 +33,13 @@
 )
 @Component
 public class GitLabCiDetector extends AbstractStructuredDetector {
+    private static final String PROP_IMAGE = "image";
+    private static final String PROP_STAGE = "stage";
+
 
     private static final Set<String> GITLAB_CI_KEYWORDS = Set.of(
             "stages", "variables", "default", "workflow", "include",
-            "image", "services", "before_script", "after_script", "cache");
+            PROP_IMAGE, "services", "before_script", "after_script", "cache");
 
     private static final List<String> TOOL_KEYWORDS = List.of(
             "docker", "helm", "kubectl", "terraform", "maven", "gradle", "npm", "pip");
@@ -88,7 +91,7 @@ public DetectorResult detect(DetectorContext ctx) {
                     NodeKind.CONFIG_KEY, "stage:" + stageStr);
             stageNode.setModule(ctx.moduleName());
             stageNode.setFilePath(fp);
-            stageNode.setProperties(Map.of("stage", stageStr));
+            stageNode.setProperties(Map.of(PROP_STAGE, stageStr));
             nodes.add(stageNode);
         }
 
@@ -150,10 +153,10 @@ public DetectorResult detect(DetectorContext ctx) {
             String jobId = jobIds.get(jobName);
 
             Map<String, Object> props = new HashMap<>();
-            String stageVal = getString(jobDef, "stage");
-            if (stageVal != null) props.put("stage", stageVal);
-            String imageVal = getString(jobDef, "image");
-            if (imageVal != null) props.put("image", imageVal);
+            String stageVal = getString(jobDef, PROP_STAGE);
+            if (stageVal != null) props.put(PROP_STAGE, stageVal);
+            String imageVal = getString(jobDef, PROP_IMAGE);
+            if (imageVal != null) props.put(PROP_IMAGE, imageVal);
 
             List<Object> scripts = getList(jobDef, "script");
             List<String> tools = detectTools(scripts);
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/HelmChartDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/HelmChartDetector.java
index d6608106..120d3055 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/HelmChartDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/HelmChartDetector.java
@@ -35,6 +35,9 @@
 )
 @Component
 public class HelmChartDetector extends AbstractStructuredDetector {
+    private static final String PROP_TYPE = "type";
+    private static final String PROP_VERSION = "version";
+
 
     private static final Pattern VALUES_REF_RE = Pattern.compile(
             "\\{\\{\\s*\\.Values\\.([a-zA-Z0-9_.]+)\\s*\\}\\}");
@@ -76,13 +79,13 @@ private void detectChartYaml(DetectorContext ctx, List<CodeNode> nodes, List<Cod
         if (data == null) return;
 
         String chartName = getStringOrDefault(data, "name", "unknown");
-        String chartVersion = getStringOrDefault(data, "version", "0.0.0");
+        String chartVersion = getStringOrDefault(data, PROP_VERSION, "0.0.0");
         String chartNodeId = "helm:" + fp + ":chart:" + chartName;
 
         Map<String, Object> props = new HashMap<>();
         props.put("chart_name", chartName);
         props.put("chart_version", chartVersion);
-        props.put("type", "helm_chart");
+        props.put(PROP_TYPE, "helm_chart");
 
         CodeNode chartNode = new CodeNode(chartNodeId, NodeKind.MODULE, "helm:" + chartName);
         chartNode.setFqn("helm:" + chartName + ":" + chartVersion);
@@ -100,7 +103,7 @@ private void detectChartYaml(DetectorContext ctx, List<CodeNode> nodes, List<Cod
             String depName = getString(depMap, "name");
             if (depName == null || depName.isEmpty()) continue;
 
-            String depVersion = getStringOrDefault(depMap, "version", "");
+            String depVersion = getStringOrDefault(depMap, PROP_VERSION, "");
             String depRepo = getStringOrDefault(depMap, "repository", "");
             String depNodeId = "helm:" + fp + ":dep:" + depName;
 
@@ -108,7 +111,7 @@ private void detectChartYaml(DetectorContext ctx, List<CodeNode> nodes, List<Cod
             depProps.put("chart_name", depName);
             depProps.put("chart_version", depVersion);
             depProps.put("repository", depRepo);
-            depProps.put("type", "helm_dependency");
+            depProps.put(PROP_TYPE, "helm_dependency");
 
             CodeNode depNode = new CodeNode(depNodeId, NodeKind.MODULE, "helm-dep:" + depName);
             depNode.setFqn("helm:" + depName + ":" + depVersion);
@@ -122,7 +125,7 @@ private void detectChartYaml(DetectorContext ctx, List<CodeNode> nodes, List<Cod
             edge.setKind(EdgeKind.DEPENDS_ON);
             edge.setSourceId(chartNodeId);
             edge.setTarget(new CodeNode(depNodeId, null, null));
-            edge.setProperties(Map.of("version", depVersion));
+            edge.setProperties(Map.of(PROP_VERSION, depVersion));
             edges.add(edge);
         }
     }
@@ -191,7 +194,7 @@ private Map<String, Object> getYamlData(DetectorContext ctx) {
         if (parsedData == null) return null;
 
         Map<String, Object> pd = asMap(parsedData);
-        if (!"yaml".equals(getString(pd, "type"))) return null;
+        if (!"yaml".equals(getString(pd, PROP_TYPE))) return null;
 
         Map<String, Object> data = getMap(pd, "data");
         return data.isEmpty() ? null : data;
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/IniStructureDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/IniStructureDetector.java
index 82212c40..56fb93cf 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/IniStructureDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/IniStructureDetector.java
@@ -19,7 +19,7 @@
 /**
  * Detects INI file structures: sections, keys, and file identity.
  * <p>
- * Expects parsedData to be a Map with type "ini" and "data" containing
+ * Expects parsedData to be a Map with type PROP_INI and "data" containing
  * a Map of section names to Maps of key-value pairs.
  */
 @DetectorInfo(
@@ -33,6 +33,8 @@
 )
 @Component
 public class IniStructureDetector extends AbstractStructuredDetector {
+    private static final String PROP_INI = "ini";
+
 
     @Override
     public String getName() {
@@ -41,7 +43,7 @@ public String getName() {
 
     @Override
     public Set<String> getSupportedLanguages() {
-        return Set.of("ini");
+        return Set.of(PROP_INI);
     }
 
     @Override
@@ -52,7 +54,7 @@ public DetectorResult detect(DetectorContext ctx) {
         List<CodeEdge> edges = new ArrayList<>();
 
         // CONFIG_FILE node for the file itself
-        nodes.add(buildFileNode(ctx, "ini"));
+        nodes.add(buildFileNode(ctx, PROP_INI));
 
         Object parsedData = ctx.parsedData();
         if (parsedData == null) {
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/JsonStructureDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/JsonStructureDetector.java
index 60d9f979..4d544edd 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/JsonStructureDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/JsonStructureDetector.java
@@ -30,6 +30,8 @@
 )
 @Component
 public class JsonStructureDetector extends AbstractStructuredDetector {
+    private static final String PROP_JSON = "json";
+
 
     @Override
     public String getName() {
@@ -38,7 +40,7 @@ public String getName() {
 
     @Override
     public Set<String> getSupportedLanguages() {
-        return Set.of("json");
+        return Set.of(PROP_JSON);
     }
 
     @Override
@@ -49,7 +51,7 @@ public DetectorResult detect(DetectorContext ctx) {
         List<CodeEdge> edges = new ArrayList<>();
 
         // CONFIG_FILE node for the file itself
-        nodes.add(buildFileNode(ctx, "json"));
+        nodes.add(buildFileNode(ctx, PROP_JSON));
 
         // Extract data from parsed_data
         Object parsedData = ctx.parsedData();
@@ -65,7 +67,7 @@ public DetectorResult detect(DetectorContext ctx) {
         }
 
         for (String key : data.keySet()) {
-            addKeyNode(fileId, fp, key, "json", ctx, nodes, edges);
+            addKeyNode(fileId, fp, key, PROP_JSON, ctx, nodes, edges);
         }
 
         return DetectorResult.of(nodes, edges);
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/KubernetesDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/KubernetesDetector.java
index db226263..50714572 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/KubernetesDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/KubernetesDetector.java
@@ -33,18 +33,32 @@
 )
 @Component
 public class KubernetesDetector extends AbstractStructuredDetector {
+    private static final String PROP_CRONJOB = "CronJob";
+    private static final String PROP_DAEMONSET = "DaemonSet";
+    private static final String PROP_DEPLOYMENT = "Deployment";
+    private static final String PROP_POD = "Pod";
+    private static final String PROP_STATEFULSET = "StatefulSet";
+    private static final String PROP_DEFAULT = "default";
+    private static final String PROP_KIND = "kind";
+    private static final String PROP_LABELS = "labels";
+    private static final String PROP_METADATA = "metadata";
+    private static final String PROP_NAME = "name";
+    private static final String PROP_NAMESPACE = "namespace";
+    private static final String PROP_SELECTOR = "selector";
+    private static final String PROP_SPEC = "spec";
+
 
     private static final Set<String> K8S_KINDS = Set.of(
-            "Deployment", "Service", "ConfigMap", "Secret", "Ingress",
-            "Pod", "StatefulSet", "DaemonSet", "Job", "CronJob",
+            PROP_DEPLOYMENT, "Service", "ConfigMap", "Secret", "Ingress",
+            PROP_POD, PROP_STATEFULSET, PROP_DAEMONSET, "Job", PROP_CRONJOB,
             "Namespace", "PersistentVolumeClaim", "ServiceAccount",
             "Role", "RoleBinding", "ClusterRole", "ClusterRoleBinding");
 
     private static final Set<String> WORKLOAD_KINDS = Set.of(
-            "Deployment", "StatefulSet", "DaemonSet", "Job", "CronJob", "Pod");
+            PROP_DEPLOYMENT, PROP_STATEFULSET, PROP_DAEMONSET, "Job", PROP_CRONJOB, PROP_POD);
 
     private static final Set<String> LABEL_TRACKING_KINDS = Set.of(
-            "Deployment", "StatefulSet", "DaemonSet");
+            PROP_DEPLOYMENT, PROP_STATEFULSET, PROP_DAEMONSET);
 
     @Override
     public String getName() {
@@ -73,20 +87,20 @@ public DetectorResult detect(DetectorContext ctx) {
         List<IngressBackend> ingressBackends = new ArrayList<>();
 
         for (Map<String, Object> doc : documents) {
-            String kind = safeStr(doc.get("kind"));
-            Map<String, Object> metadata = asMap(doc.get("metadata"));
-            String name = safeStr(metadata.getOrDefault("name", "unknown"));
-            String namespace = safeStr(metadata.getOrDefault("namespace", "default"));
-            if (namespace.isEmpty()) namespace = "default";
+            String kind = safeStr(doc.get(PROP_KIND));
+            Map<String, Object> metadata = asMap(doc.get(PROP_METADATA));
+            String name = safeStr(metadata.getOrDefault(PROP_NAME, "unknown"));
+            String namespace = safeStr(metadata.getOrDefault(PROP_NAMESPACE, PROP_DEFAULT));
+            if (namespace.isEmpty()) namespace = PROP_DEFAULT;
 
             String nodeId = "k8s:" + fp + ":" + kind + ":" + namespace + "/" + name;
 
             Map<String, Object> props = new HashMap<>();
-            props.put("kind", kind);
-            props.put("namespace", namespace);
-            Object labels = metadata.get("labels");
+            props.put(PROP_KIND, kind);
+            props.put(PROP_NAMESPACE, namespace);
+            Object labels = metadata.get(PROP_LABELS);
             if (labels instanceof Map<?, ?>) {
-                props.put("labels", labels);
+                props.put(PROP_LABELS, labels);
             }
             Object annotations = metadata.get("annotations");
             if (annotations instanceof Map<?, ?>) {
@@ -101,13 +115,13 @@ public DetectorResult detect(DetectorContext ctx) {
             resourceNode.setProperties(props);
             nodes.add(resourceNode);
 
-            Map<String, Object> spec = asMap(doc.get("spec"));
+            Map<String, Object> spec = asMap(doc.get(PROP_SPEC));
 
             // Extract container specs from workload resources
             if (WORKLOAD_KINDS.contains(kind)) {
                 List<Map<String, Object>> containers = extractContainers(spec, kind);
                 for (Map<String, Object> container : containers) {
-                    String cName = safeStr(container.getOrDefault("name", "unnamed"));
+                    String cName = safeStr(container.getOrDefault(PROP_NAME, "unnamed"));
                     Map<String, Object> cProps = new HashMap<>();
 
                     String image = getString(container, "image");
@@ -135,7 +149,7 @@ public DetectorResult detect(DetectorContext ctx) {
                         List<String> envNames = new ArrayList<>();
                         for (Object e : envVars) {
                             Map<String, Object> em = asMap(e);
-                            String envName = getString(em, "name");
+                            String envName = getString(em, PROP_NAME);
                             if (envName != null) {
                                 envNames.add(envName);
                             }
@@ -157,13 +171,13 @@ public DetectorResult detect(DetectorContext ctx) {
             // Track deployment match labels
             if (LABEL_TRACKING_KINDS.contains(kind)) {
                 Map<String, Object> template = getMap(spec, "template");
-                Map<String, Object> tmplMeta = getMap(template, "metadata");
-                Map<String, Object> tmplLabels = getMap(tmplMeta, "labels");
+                Map<String, Object> tmplMeta = getMap(template, PROP_METADATA);
+                Map<String, Object> tmplLabels = getMap(tmplMeta, PROP_LABELS);
                 for (var le : tmplLabels.entrySet()) {
                     deploymentLabels.put(le.getKey() + "=" + le.getValue(), nodeId);
                 }
 
-                Map<String, Object> selector = getMap(spec, "selector");
+                Map<String, Object> selector = getMap(spec, PROP_SELECTOR);
                 Map<String, Object> matchLabels = getMap(selector, "matchLabels");
                 for (var le : matchLabels.entrySet()) {
                     deploymentLabels.put(le.getKey() + "=" + le.getValue(), nodeId);
@@ -172,7 +186,7 @@ public DetectorResult detect(DetectorContext ctx) {
 
             // Track service selectors
             if ("Service".equals(kind)) {
-                Map<String, Object> svcSelector = getMap(spec, "selector");
+                Map<String, Object> svcSelector = getMap(spec, PROP_SELECTOR);
                 if (!svcSelector.isEmpty()) {
                     serviceSelectors.add(new SelectorEntry(nodeId, svcSelector));
                 }
@@ -191,7 +205,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 String targetId = deploymentLabels.get(labelTag);
                 if (targetId != null) {
                     edges.add(createEdge(se.nodeId, targetId, EdgeKind.DEPENDS_ON,
-                            "service selects " + labelTag, Map.of("selector", labelTag)));
+                            "service selects " + labelTag, Map.of(PROP_SELECTOR, labelTag)));
                 }
             }
         }
@@ -199,11 +213,11 @@ public DetectorResult detect(DetectorContext ctx) {
         // Resolve ingress -> service edges
         Map<String, String> serviceNameToId = new LinkedHashMap<>();
         for (Map<String, Object> doc : documents) {
-            if (!"Service".equals(doc.get("kind"))) continue;
-            Map<String, Object> meta = asMap(doc.get("metadata"));
-            String svcName = safeStr(meta.getOrDefault("name", ""));
-            String ns = safeStr(meta.getOrDefault("namespace", "default"));
-            if (ns.isEmpty()) ns = "default";
+            if (!"Service".equals(doc.get(PROP_KIND))) continue;
+            Map<String, Object> meta = asMap(doc.get(PROP_METADATA));
+            String svcName = safeStr(meta.getOrDefault(PROP_NAME, ""));
+            String ns = safeStr(meta.getOrDefault(PROP_NAMESPACE, PROP_DEFAULT));
+            if (ns.isEmpty()) ns = PROP_DEFAULT;
             serviceNameToId.put(svcName, "k8s:" + fp + ":Service:" + ns + "/" + svcName);
         }
 
@@ -230,7 +244,7 @@ private List<Map<String, Object>> getDocuments(DetectorContext ctx) {
             List<Map<String, Object>> result = new ArrayList<>();
             for (Object d : docs) {
                 Map<String, Object> doc = asMap(d);
-                String docKind = getString(doc, "kind");
+                String docKind = getString(doc, PROP_KIND);
                 if (docKind != null && K8S_KINDS.contains(docKind)) {
                     result.add(doc);
                 }
@@ -240,7 +254,7 @@ private List<Map<String, Object>> getDocuments(DetectorContext ctx) {
 
         if ("yaml".equals(ptype)) {
             Map<String, Object> data = getMap(pd, "data");
-            String dataKind = getString(data, "kind");
+            String dataKind = getString(data, PROP_KIND);
             if (dataKind != null && K8S_KINDS.contains(dataKind)) {
                 return List.of(data);
             }
@@ -265,12 +279,12 @@ private List<Map<String, Object>> extractContainers(Map<String, Object> spec, St
         Map<String, Object> workSpec = spec;
         if ("CronJob".equals(kind)) {
             Map<String, Object> jobTemplate = getMap(spec, "jobTemplate");
-            workSpec = getMap(jobTemplate, "spec");
+            workSpec = getMap(jobTemplate, PROP_SPEC);
             if (workSpec.isEmpty()) return containers;
         }
 
         Map<String, Object> template = getMap(workSpec, "template");
-        Map<String, Object> podSpec = getMap(template, "spec");
+        Map<String, Object> podSpec = getMap(template, PROP_SPEC);
 
         List<Object> cs = getList(podSpec, "containers");
         for (Object c : cs) {
@@ -296,7 +310,7 @@ private void collectIngressBackends(Map<String, Object> spec, String ingressNode
         if (!defaultBackend.isEmpty()) {
             Map<String, Object> svc = getMap(defaultBackend, "service");
             if (svc.isEmpty()) svc = defaultBackend;
-            String svcName = getString(svc, "name");
+            String svcName = getString(svc, PROP_NAME);
             if (svcName == null) svcName = getString(svc, "serviceName");
             if (svcName != null) {
                 out.add(new IngressBackend(ingressNodeId, svcName));
@@ -315,7 +329,7 @@ private void collectIngressBackends(Map<String, Object> spec, String ingressNode
                 if (backend.isEmpty()) continue;
                 Map<String, Object> svc = getMap(backend, "service");
                 if (svc.isEmpty()) svc = backend;
-                String svcName = getString(svc, "name");
+                String svcName = getString(svc, PROP_NAME);
                 if (svcName == null) svcName = getString(svc, "serviceName");
                 if (svcName != null) {
                     out.add(new IngressBackend(ingressNodeId, svcName));
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/KubernetesRbacDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/KubernetesRbacDetector.java
index aef31d03..b5131125 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/KubernetesRbacDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/KubernetesRbacDetector.java
@@ -10,7 +10,6 @@
 import org.springframework.stereotype.Component;
 
 import java.util.ArrayList;
-import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
@@ -33,9 +32,20 @@
 )
 @Component
 public class KubernetesRbacDetector extends AbstractStructuredDetector {
+    private static final String PROP_CLUSTERROLE = "ClusterRole";
+    private static final String PROP_SERVICEACCOUNT = "ServiceAccount";
+    private static final String PROP_AUTH_TYPE = "auth_type";
+    private static final String PROP_DEFAULT = "default";
+    private static final String PROP_K8S_KIND = "k8s_kind";
+    private static final String PROP_K8S_RBAC = "k8s_rbac";
+    private static final String PROP_KIND = "kind";
+    private static final String PROP_NAME = "name";
+    private static final String PROP_NAMESPACE = "namespace";
+    private static final String PROP_RULES = "rules";
+
 
     private static final Set<String> RBAC_KINDS = Set.of(
-            "Role", "ClusterRole", "RoleBinding", "ClusterRoleBinding", "ServiceAccount");
+            "Role", PROP_CLUSTERROLE, "RoleBinding", "ClusterRoleBinding", PROP_SERVICEACCOUNT);
 
     @Override
     public String getName() {
@@ -63,16 +73,16 @@ public DetectorResult detect(DetectorContext ctx) {
         List<Map<String, Object>> bindings = new ArrayList<>();
 
         for (Map<String, Object> doc : documents) {
-            String kind = safeStr(doc.get("kind"));
+            String kind = safeStr(doc.get(PROP_KIND));
             Map<String, Object> metadata = asMap(doc.get("metadata"));
-            String name = safeStr(metadata.getOrDefault("name", "unknown"));
-            String namespace = safeStr(metadata.getOrDefault("namespace", "default"));
-            if (namespace.isEmpty()) namespace = "default";
+            String name = safeStr(metadata.getOrDefault(PROP_NAME, "unknown"));
+            String namespace = safeStr(metadata.getOrDefault(PROP_NAMESPACE, PROP_DEFAULT));
+            if (namespace.isEmpty()) namespace = PROP_DEFAULT;
 
             String nodeId = "k8s_rbac:" + fp + ":" + kind + ":" + namespace + "/" + name;
 
             if ("Role".equals(kind) || "ClusterRole".equals(kind)) {
-                List<Object> rules = getList(doc, "rules");
+                List<Object> rules = getList(doc, PROP_RULES);
                 List<Map<String, Object>> serializedRules = new ArrayList<>();
                 for (Object rule : rules) {
                     Map<String, Object> rm = asMap(rule);
@@ -86,10 +96,10 @@ public DetectorResult detect(DetectorContext ctx) {
                 }
 
                 Map<String, Object> props = new LinkedHashMap<>();
-                props.put("auth_type", "k8s_rbac");
-                props.put("k8s_kind", kind);
-                props.put("namespace", namespace);
-                props.put("rules", serializedRules);
+                props.put(PROP_AUTH_TYPE, PROP_K8S_RBAC);
+                props.put(PROP_K8S_KIND, kind);
+                props.put(PROP_NAMESPACE, namespace);
+                props.put(PROP_RULES, serializedRules);
 
                 CodeNode node = new CodeNode(nodeId, NodeKind.GUARD, kind + "/" + name);
                 node.setFqn("k8s:" + kind + ":" + namespace + "/" + name);
@@ -105,10 +115,10 @@ public DetectorResult detect(DetectorContext ctx) {
 
             } else if ("ServiceAccount".equals(kind)) {
                 Map<String, Object> props = new LinkedHashMap<>();
-                props.put("auth_type", "k8s_rbac");
-                props.put("k8s_kind", "ServiceAccount");
-                props.put("namespace", namespace);
-                props.put("rules", List.of());
+                props.put(PROP_AUTH_TYPE, PROP_K8S_RBAC);
+                props.put(PROP_K8S_KIND, PROP_SERVICEACCOUNT);
+                props.put(PROP_NAMESPACE, namespace);
+                props.put(PROP_RULES, List.of());
 
                 CodeNode node = new CodeNode(nodeId, NodeKind.GUARD,
                         "ServiceAccount/" + name);
@@ -122,10 +132,10 @@ public DetectorResult detect(DetectorContext ctx) {
 
             } else if ("RoleBinding".equals(kind) || "ClusterRoleBinding".equals(kind)) {
                 Map<String, Object> props = new LinkedHashMap<>();
-                props.put("auth_type", "k8s_rbac");
-                props.put("k8s_kind", kind);
-                props.put("namespace", namespace);
-                props.put("rules", List.of());
+                props.put(PROP_AUTH_TYPE, PROP_K8S_RBAC);
+                props.put(PROP_K8S_KIND, kind);
+                props.put(PROP_NAMESPACE, namespace);
+                props.put(PROP_RULES, List.of());
 
                 CodeNode node = new CodeNode(nodeId, NodeKind.GUARD, kind + "/" + name);
                 node.setFqn("k8s:" + kind + ":" + namespace + "/" + name);
@@ -140,16 +150,16 @@ public DetectorResult detect(DetectorContext ctx) {
 
         // Resolve RoleBinding/ClusterRoleBinding -> PROTECTS edges
         for (Map<String, Object> doc : bindings) {
-            String kind = safeStr(doc.get("kind"));
+            String kind = safeStr(doc.get(PROP_KIND));
             Map<String, Object> metadata = asMap(doc.get("metadata"));
-            String bindingNamespace = safeStr(metadata.getOrDefault("namespace", "default"));
-            if (bindingNamespace.isEmpty()) bindingNamespace = "default";
+            String bindingNamespace = safeStr(metadata.getOrDefault(PROP_NAMESPACE, PROP_DEFAULT));
+            if (bindingNamespace.isEmpty()) bindingNamespace = PROP_DEFAULT;
 
             Map<String, Object> roleRef = getMap(doc, "roleRef");
             if (roleRef.isEmpty()) continue;
 
-            String refKind = safeStr(roleRef.get("kind"));
-            String refName = safeStr(roleRef.get("name"));
+            String refKind = safeStr(roleRef.get(PROP_KIND));
+            String refName = safeStr(roleRef.get(PROP_NAME));
 
             String roleKey = "ClusterRole".equals(refKind)
                     ? "ClusterRole:cluster-wide/" + refName
@@ -163,9 +173,9 @@ public DetectorResult detect(DetectorContext ctx) {
                 Map<String, Object> subj = asMap(subject);
                 if (subj.isEmpty()) continue;
 
-                String subjKind = safeStr(subj.get("kind"));
-                String subjName = safeStr(subj.get("name"));
-                String subjNamespace = safeStr(subj.getOrDefault("namespace", bindingNamespace));
+                String subjKind = safeStr(subj.get(PROP_KIND));
+                String subjName = safeStr(subj.get(PROP_NAME));
+                String subjNamespace = safeStr(subj.getOrDefault(PROP_NAMESPACE, bindingNamespace));
                 if (subjNamespace.isEmpty()) subjNamespace = bindingNamespace;
 
                 if ("ServiceAccount".equals(subjKind)) {
@@ -199,7 +209,7 @@ private List<Map<String, Object>> getDocuments(DetectorContext ctx) {
             List<Map<String, Object>> result = new ArrayList<>();
             for (Object d : docs) {
                 Map<String, Object> doc = asMap(d);
-                String docKind = getString(doc, "kind");
+                String docKind = getString(doc, PROP_KIND);
                 if (docKind != null && RBAC_KINDS.contains(docKind)) {
                     result.add(doc);
                 }
@@ -209,7 +219,7 @@ private List<Map<String, Object>> getDocuments(DetectorContext ctx) {
 
         if ("yaml".equals(ptype)) {
             Map<String, Object> data = getMap(pd, "data");
-            String dataKind = getString(data, "kind");
+            String dataKind = getString(data, PROP_KIND);
             if (dataKind != null && RBAC_KINDS.contains(dataKind)) {
                 return List.of(data);
             }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/OpenApiDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/OpenApiDetector.java
index d5132921..3e8970a3 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/OpenApiDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/OpenApiDetector.java
@@ -33,13 +33,15 @@
 )
 @Component
 public class OpenApiDetector extends AbstractStructuredDetector {
+    private static final String PROP_OPENAPI = "openapi";
+
 
     private static final Set<String> HTTP_METHODS = Set.of(
             "get", "post", "put", "patch", "delete", "head", "options", "trace");
 
     @Override
     public String getName() {
-        return "openapi";
+        return PROP_OPENAPI;
     }
 
     @Override
@@ -57,7 +59,7 @@ public DetectorResult detect(DetectorContext ctx) {
         if (spec.isEmpty()) return DetectorResult.empty();
 
         // Only trigger for OpenAPI or Swagger spec
-        if (!spec.containsKey("openapi") && !spec.containsKey("swagger")) {
+        if (!spec.containsKey(PROP_OPENAPI) && !spec.containsKey("swagger")) {
             return DetectorResult.empty();
         }
 
@@ -71,13 +73,13 @@ public DetectorResult detect(DetectorContext ctx) {
         String apiTitle = getString(info, "title");
         if (apiTitle == null) apiTitle = filepath;
         String apiVersion = getStringOrDefault(info, "version", "");
-        Object specVersionObj = spec.get("openapi");
+        Object specVersionObj = spec.get(PROP_OPENAPI);
         if (specVersionObj == null) specVersionObj = spec.get("swagger");
         String specVersion = specVersionObj != null ? String.valueOf(specVersionObj) : "";
 
         // CONFIG_FILE node for the spec
         Map<String, Object> cfProps = new HashMap<>();
-        cfProps.put("config_type", "openapi");
+        cfProps.put("config_type", PROP_OPENAPI);
         cfProps.put("api_title", apiTitle);
         cfProps.put("api_version", apiVersion);
         cfProps.put("spec_version", specVersion);
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/PropertiesDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/PropertiesDetector.java
index 44556db5..31e34d90 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/PropertiesDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/PropertiesDetector.java
@@ -34,6 +34,8 @@
 )
 @Component
 public class PropertiesDetector extends AbstractStructuredDetector {
+    private static final String PROP_PROPERTIES = "properties";
+
 
     private static final Set<String> DB_URL_KEYWORDS = Set.of("url", "jdbc-url", "uri");
     private static final Pattern JDBC_DB_TYPE_RE = Pattern.compile(
@@ -54,12 +56,12 @@ public class PropertiesDetector extends AbstractStructuredDetector {
 
     @Override
     public String getName() {
-        return "properties";
+        return PROP_PROPERTIES;
     }
 
     @Override
     public Set<String> getSupportedLanguages() {
-        return Set.of("properties");
+        return Set.of(PROP_PROPERTIES);
     }
 
     @Override
@@ -86,7 +88,7 @@ public DetectorResult detect(DetectorContext ctx) {
         fileNode.setModule(ctx.moduleName());
         fileNode.setFilePath(filepath);
         fileNode.setLineStart(1);
-        fileNode.setProperties(Map.of("format", "properties"));
+        fileNode.setProperties(Map.of("format", PROP_PROPERTIES));
         nodes.add(fileNode);
 
         // Process keys (limit to avoid node explosion)
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/PyprojectTomlDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/PyprojectTomlDetector.java
index e52d6ba4..b2368d96 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/PyprojectTomlDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/PyprojectTomlDetector.java
@@ -35,6 +35,9 @@
 )
 @Component
 public class PyprojectTomlDetector extends AbstractStructuredDetector {
+    private static final String PROP_DESCRIPTION = "description";
+    private static final String PROP_VERSION = "version";
+
 
     @Override
     public String getName() {
@@ -76,12 +79,12 @@ public DetectorResult detect(DetectorContext ctx) {
 
         Map<String, Object> props = new HashMap<>();
         props.put("package_name", pkgName);
-        String version = getString(projectSection, "version");
-        if (version == null) version = getString(poetrySection, "version");
-        if (version != null) props.put("version", version);
-        String description = getString(projectSection, "description");
-        if (description == null) description = getString(poetrySection, "description");
-        if (description != null) props.put("description", description);
+        String version = getString(projectSection, PROP_VERSION);
+        if (version == null) version = getString(poetrySection, PROP_VERSION);
+        if (version != null) props.put(PROP_VERSION, version);
+        String description = getString(projectSection, PROP_DESCRIPTION);
+        if (description == null) description = getString(poetrySection, PROP_DESCRIPTION);
+        if (description != null) props.put(PROP_DESCRIPTION, description);
 
         CodeNode moduleNode = new CodeNode(moduleId, NodeKind.MODULE, pkgName);
         moduleNode.setFqn(pkgName);
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/SqlStructureDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/SqlStructureDetector.java
index 452c1baa..f6c4da59 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/SqlStructureDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/SqlStructureDetector.java
@@ -31,6 +31,8 @@
 )
 @Component
 public class SqlStructureDetector extends AbstractRegexDetector {
+    private static final String PROP_ENTITY_TYPE = "entity_type";
+
 
     private static final Pattern TABLE_RE = Pattern.compile(
             "CREATE\\s+TABLE\\s+(?:IF\\s+NOT\\s+EXISTS\\s+)?(?:\\w+\\.)?(\\w+)",
@@ -67,7 +69,6 @@ public DetectorResult detect(DetectorContext ctx) {
         List<CodeNode> nodes = new ArrayList<>();
         List<CodeEdge> edges = new ArrayList<>();
 
-        String currentTable = null;
         String currentTableId = null;
 
         for (IndexedLine il : iterLines(content)) {
@@ -79,7 +80,6 @@ public DetectorResult detect(DetectorContext ctx) {
             m = TABLE_RE.matcher(line);
             if (m.find()) {
                 String tableName = m.group(1);
-                currentTable = tableName;
                 currentTableId = "sql:" + filepath + ":table:" + tableName;
 
                 CodeNode node = new CodeNode(currentTableId, NodeKind.ENTITY, tableName);
@@ -87,7 +87,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 node.setModule(ctx.moduleName());
                 node.setFilePath(filepath);
                 node.setLineStart(lineNum);
-                node.setProperties(Map.of("entity_type", "table"));
+                node.setProperties(Map.of(PROP_ENTITY_TYPE, "table"));
                 nodes.add(node);
                 continue;
             }
@@ -102,9 +102,8 @@ public DetectorResult detect(DetectorContext ctx) {
                 node.setModule(ctx.moduleName());
                 node.setFilePath(filepath);
                 node.setLineStart(lineNum);
-                node.setProperties(Map.of("entity_type", "view"));
+                node.setProperties(Map.of(PROP_ENTITY_TYPE, "view"));
                 nodes.add(node);
-                currentTable = null;
                 currentTableId = null;
                 continue;
             }
@@ -134,9 +133,8 @@ public DetectorResult detect(DetectorContext ctx) {
                 node.setModule(ctx.moduleName());
                 node.setFilePath(filepath);
                 node.setLineStart(lineNum);
-                node.setProperties(Map.of("entity_type", "procedure"));
+                node.setProperties(Map.of(PROP_ENTITY_TYPE, "procedure"));
                 nodes.add(node);
-                currentTable = null;
                 currentTableId = null;
                 continue;
             }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/TomlStructureDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/TomlStructureDetector.java
index fed52902..9e6446fe 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/TomlStructureDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/TomlStructureDetector.java
@@ -21,7 +21,7 @@
 /**
  * Detects TOML file structures: sections, top-level keys, and file identity.
  * <p>
- * Expects parsedData to be a Map with type "toml" and "data" containing the parsed structure.
+ * Expects parsedData to be a Map with type PROP_TOML and "data" containing the parsed structure.
  */
 @DetectorInfo(
     name = "toml_structure",
@@ -34,6 +34,8 @@
 )
 @Component
 public class TomlStructureDetector extends AbstractStructuredDetector {
+    private static final String PROP_TOML = "toml";
+
 
     @Override
     public String getName() {
@@ -42,7 +44,7 @@ public String getName() {
 
     @Override
     public Set<String> getSupportedLanguages() {
-        return Set.of("toml");
+        return Set.of(PROP_TOML);
     }
 
     @Override
@@ -53,7 +55,7 @@ public DetectorResult detect(DetectorContext ctx) {
         List<CodeEdge> edges = new ArrayList<>();
 
         // CONFIG_FILE node for the file itself
-        nodes.add(buildFileNode(ctx, "toml"));
+        nodes.add(buildFileNode(ctx, PROP_TOML));
 
         Object parsedData = ctx.parsedData();
         if (parsedData == null) {
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/TsconfigJsonDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/TsconfigJsonDetector.java
index 4e6ace24..b6972d51 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/TsconfigJsonDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/TsconfigJsonDetector.java
@@ -33,6 +33,8 @@
 )
 @Component
 public class TsconfigJsonDetector extends AbstractStructuredDetector {
+    private static final String PROP_EXTENDS = "extends";
+
 
     private static final Pattern TSCONFIG_RE = Pattern.compile("^tsconfig(?:\\..+)?\\.json$");
     private static final List<String> TRACKED_COMPILER_OPTIONS = List.of(
@@ -75,15 +77,15 @@ public DetectorResult detect(DetectorContext ctx) {
         configNode.setProperties(Map.of("config_type", "tsconfig"));
         nodes.add(configNode);
 
-        // DEPENDS_ON edge for "extends"
-        String extendsVal = getString(cfg, "extends");
+        // DEPENDS_ON edge for PROP_EXTENDS
+        String extendsVal = getString(cfg, PROP_EXTENDS);
         if (extendsVal != null && !extendsVal.isEmpty()) {
             CodeEdge edge = new CodeEdge();
             edge.setId(configId + "->" + extendsVal);
             edge.setKind(EdgeKind.DEPENDS_ON);
             edge.setSourceId(configId);
             edge.setTarget(new CodeNode(extendsVal, null, null));
-            edge.setProperties(Map.of("relation", "extends"));
+            edge.setProperties(Map.of("relation", PROP_EXTENDS));
             edges.add(edge);
         }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/config/YamlStructureDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/config/YamlStructureDetector.java
index 4b529872..0b0b8e1b 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/config/YamlStructureDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/config/YamlStructureDetector.java
@@ -31,6 +31,8 @@
 )
 @Component
 public class YamlStructureDetector extends AbstractStructuredDetector {
+    private static final String PROP_YAML = "yaml";
+
 
     @Override
     public String getName() {
@@ -39,7 +41,7 @@ public String getName() {
 
     @Override
     public Set<String> getSupportedLanguages() {
-        return Set.of("yaml");
+        return Set.of(PROP_YAML);
     }
 
     @Override
@@ -50,7 +52,7 @@ public DetectorResult detect(DetectorContext ctx) {
         List<CodeEdge> edges = new ArrayList<>();
 
         // CONFIG_FILE node for the file itself
-        nodes.add(buildFileNode(ctx, "yaml"));
+        nodes.add(buildFileNode(ctx, PROP_YAML));
 
         Object parsedData = ctx.parsedData();
         if (parsedData == null) {
@@ -78,7 +80,7 @@ public DetectorResult detect(DetectorContext ctx) {
         }
 
         for (String keyStr : topLevelKeys) {
-            addKeyNode(fileId, fp, keyStr, "yaml", ctx, nodes, edges);
+            addKeyNode(fileId, fp, keyStr, PROP_YAML, ctx, nodes, edges);
         }
 
         return DetectorResult.of(nodes, edges);
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/csharp/CSharpEfcoreDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/csharp/CSharpEfcoreDetector.java
index 36fb55f6..f30261d0 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/csharp/CSharpEfcoreDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/csharp/CSharpEfcoreDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.csharp;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeEdge;
@@ -30,6 +29,9 @@
 )
 @Component
 public class CSharpEfcoreDetector extends AbstractAntlrDetector {
+    private static final String PROP_EFCORE = "efcore";
+    private static final String PROP_FRAMEWORK = "framework";
+
 
     private static final Pattern DBCONTEXT_RE = Pattern.compile("class\\s+(\\w+)\\s*:\\s*(?:[\\w.]+\\.)?DbContext", Pattern.MULTILINE);
     private static final Pattern DBSET_RE = Pattern.compile("DbSet<(\\w+)>", Pattern.MULTILINE);
@@ -71,7 +73,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFqn(contextName);
             node.setFilePath(filePath);
             node.setLineStart(findLineNumber(text, m.start()));
-            node.getProperties().put("framework", "efcore");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_EFCORE);
             nodes.add(node);
         }
 
@@ -87,7 +89,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFqn(entityName);
             node.setFilePath(filePath);
             node.setLineStart(findLineNumber(text, m.start()));
-            node.getProperties().put("framework", "efcore");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_EFCORE);
             nodes.add(node);
 
             for (String ctxId : contextIds) {
@@ -111,7 +113,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFqn(migrationName);
             node.setFilePath(filePath);
             node.setLineStart(findLineNumber(text, m.start()));
-            node.getProperties().put("framework", "efcore");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_EFCORE);
             nodes.add(node);
         }
 
@@ -129,7 +131,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setFqn(tableName);
                 node.setFilePath(filePath);
                 node.setLineStart(findLineNumber(text, m.start()));
-                node.getProperties().put("framework", "efcore");
+                node.getProperties().put(PROP_FRAMEWORK, PROP_EFCORE);
                 node.getProperties().put("source", "migration");
                 nodes.add(node);
             }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/csharp/CSharpMinimalApisDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/csharp/CSharpMinimalApisDetector.java
index 1eecfc69..50eb5fbc 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/csharp/CSharpMinimalApisDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/csharp/CSharpMinimalApisDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.csharp;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeEdge;
@@ -30,6 +29,9 @@
 )
 @Component
 public class CSharpMinimalApisDetector extends AbstractAntlrDetector {
+    private static final String PROP_DOTNET_MINIMAL_API = "dotnet_minimal_api";
+    private static final String PROP_FRAMEWORK = "framework";
+
 
     private static final Pattern MAP_RE = Pattern.compile("\\.Map(Get|Post|Put|Delete|Patch)\\s*\\(\\s*\"([^\"]*)\"", Pattern.MULTILINE);
     private static final Pattern BUILDER_RE = Pattern.compile("WebApplication\\.CreateBuilder\\s*\\(", Pattern.MULTILINE);
@@ -68,7 +70,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFqn(filePath);
             node.setFilePath(filePath);
             node.setLineStart(findLineNumber(text, bm.start()));
-            node.getProperties().put("framework", "dotnet_minimal_api");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_DOTNET_MINIMAL_API);
             nodes.add(node);
         }
 
@@ -87,7 +89,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setLineStart(line);
             node.getProperties().put("http_method", httpMethod);
             node.getProperties().put("path", path);
-            node.getProperties().put("framework", "dotnet_minimal_api");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_DOTNET_MINIMAL_API);
             nodes.add(node);
 
             if (appModuleId != null) {
@@ -114,7 +116,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setFilePath(filePath);
                 node.setLineStart(line);
                 node.getProperties().put("guard_type", authType.toLowerCase());
-                node.getProperties().put("framework", "dotnet_minimal_api");
+                node.getProperties().put(PROP_FRAMEWORK, PROP_DOTNET_MINIMAL_API);
                 nodes.add(node);
             }
         }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/frontend/AngularComponentDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/frontend/AngularComponentDetector.java
index 9160d371..2fd61ac9 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/frontend/AngularComponentDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/frontend/AngularComponentDetector.java
@@ -22,6 +22,10 @@
 )
 @Component
 public class AngularComponentDetector extends AbstractRegexDetector {
+    private static final String PROP_ANGULAR = "angular";
+    private static final String PROP_COMPONENT = "component";
+    private static final String PROP_DECORATOR = "decorator";
+
 
     private static final Pattern COMPONENT_DECORATOR = Pattern.compile(
             "@Component\\s*\\(\\s*\\{.*?selector\\s*:\\s*['\"]([^'\"]+)['\"].*?\\}\\s*\\)\\s*\\n?\\s*(?:export\\s+)?class\\s+(\\w+)",
@@ -71,10 +75,10 @@ public DetectorResult detect(DetectorContext ctx) {
             String selector = m.group(1);
             String className = m.group(2);
             if (!seen.add(className)) continue;
-            CodeNode node = FrontendDetectorHelper.createComponentNode("angular", filePath, "component",
+            CodeNode node = FrontendDetectorHelper.createComponentNode(PROP_ANGULAR, filePath, PROP_COMPONENT,
                     className, NodeKind.COMPONENT, FrontendDetectorHelper.lineAt(text, m.start()));
             node.getProperties().put("selector", selector);
-            node.getProperties().put("decorator", "Component");
+            node.getProperties().put(PROP_DECORATOR, "Component");
             nodes.add(node);
         }
 
@@ -84,10 +88,10 @@ public DetectorResult detect(DetectorContext ctx) {
             String providedIn = m.group(1);
             String className = m.group(2);
             if (!seen.add(className)) continue;
-            CodeNode node = FrontendDetectorHelper.createComponentNode("angular", filePath, "service",
+            CodeNode node = FrontendDetectorHelper.createComponentNode(PROP_ANGULAR, filePath, "service",
                     className, NodeKind.MIDDLEWARE, FrontendDetectorHelper.lineAt(text, m.start()));
             node.getProperties().put("provided_in", providedIn);
-            node.getProperties().put("decorator", "Injectable");
+            node.getProperties().put(PROP_DECORATOR, "Injectable");
             nodes.add(node);
         }
 
@@ -97,10 +101,10 @@ public DetectorResult detect(DetectorContext ctx) {
             String selector = m.group(1);
             String className = m.group(2);
             if (!seen.add(className)) continue;
-            CodeNode node = FrontendDetectorHelper.createComponentNode("angular", filePath, "component",
+            CodeNode node = FrontendDetectorHelper.createComponentNode(PROP_ANGULAR, filePath, PROP_COMPONENT,
                     className, NodeKind.COMPONENT, FrontendDetectorHelper.lineAt(text, m.start()));
             node.getProperties().put("selector", selector);
-            node.getProperties().put("decorator", "Directive");
+            node.getProperties().put(PROP_DECORATOR, "Directive");
             nodes.add(node);
         }
 
@@ -110,10 +114,10 @@ public DetectorResult detect(DetectorContext ctx) {
             String pipeName = m.group(1);
             String className = m.group(2);
             if (!seen.add(className)) continue;
-            CodeNode node = FrontendDetectorHelper.createComponentNode("angular", filePath, "component",
+            CodeNode node = FrontendDetectorHelper.createComponentNode(PROP_ANGULAR, filePath, PROP_COMPONENT,
                     className, NodeKind.COMPONENT, FrontendDetectorHelper.lineAt(text, m.start()));
             node.getProperties().put("pipe_name", pipeName);
-            node.getProperties().put("decorator", "Pipe");
+            node.getProperties().put(PROP_DECORATOR, "Pipe");
             nodes.add(node);
         }
 
@@ -122,9 +126,9 @@ public DetectorResult detect(DetectorContext ctx) {
         while (m.find()) {
             String className = m.group(1);
             if (!seen.add(className)) continue;
-            CodeNode node = FrontendDetectorHelper.createComponentNode("angular", filePath, "component",
+            CodeNode node = FrontendDetectorHelper.createComponentNode(PROP_ANGULAR, filePath, PROP_COMPONENT,
                     className, NodeKind.COMPONENT, FrontendDetectorHelper.lineAt(text, m.start()));
-            node.getProperties().put("decorator", "NgModule");
+            node.getProperties().put(PROP_DECORATOR, "NgModule");
             nodes.add(node);
         }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/frontend/ReactComponentDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/frontend/ReactComponentDetector.java
index bd87ddd8..d346483f 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/frontend/ReactComponentDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/frontend/ReactComponentDetector.java
@@ -25,6 +25,8 @@
 )
 @Component
 public class ReactComponentDetector extends AbstractRegexDetector {
+    private static final String PROP_REACT = "react";
+
 
     private static final Pattern EXPORT_DEFAULT_FUNC = Pattern.compile("export\\s+default\\s+function\\s+([A-Z]\\w*)\\s*\\(");
     private static final Pattern EXPORT_CONST_ARROW = Pattern.compile("export\\s+const\\s+([A-Z]\\w*)\\s*=\\s*\\(");
@@ -68,7 +70,7 @@ record ComponentEntry(String name, String sourceId, int matchStart) {}
                 String name = m.group(1);
                 if (componentNames.contains(name)) continue;
                 String sourceId = "react:" + filePath + ":component:" + name;
-                CodeNode node = FrontendDetectorHelper.createComponentNode("react", filePath, "component",
+                CodeNode node = FrontendDetectorHelper.createComponentNode(PROP_REACT, filePath, "component",
                         name, NodeKind.COMPONENT, FrontendDetectorHelper.lineAt(text, m.start()));
                 node.getProperties().put("component_type", "function");
                 nodes.add(node);
@@ -84,7 +86,7 @@ record ComponentEntry(String name, String sourceId, int matchStart) {}
                 String name = m.group(1);
                 if (componentNames.contains(name)) continue;
                 String sourceId = "react:" + filePath + ":component:" + name;
-                CodeNode node = FrontendDetectorHelper.createComponentNode("react", filePath, "component",
+                CodeNode node = FrontendDetectorHelper.createComponentNode(PROP_REACT, filePath, "component",
                         name, NodeKind.COMPONENT, FrontendDetectorHelper.lineAt(text, m.start()));
                 node.getProperties().put("component_type", "class");
                 nodes.add(node);
@@ -100,7 +102,7 @@ record ComponentEntry(String name, String sourceId, int matchStart) {}
             while (m.find()) {
                 String name = m.group(1);
                 if (hookNames.contains(name)) continue;
-                nodes.add(FrontendDetectorHelper.createComponentNode("react", filePath, "hook",
+                nodes.add(FrontendDetectorHelper.createComponentNode(PROP_REACT, filePath, "hook",
                         name, NodeKind.HOOK, FrontendDetectorHelper.lineAt(text, m.start())));
                 hookNames.add(name);
             }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/frontend/VueComponentDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/frontend/VueComponentDetector.java
index 8c8d85c0..70a34a74 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/frontend/VueComponentDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/frontend/VueComponentDetector.java
@@ -24,6 +24,10 @@
 )
 @Component
 public class VueComponentDetector extends AbstractRegexDetector {
+    private static final String PROP_API_STYLE = "api_style";
+    private static final String PROP_COMPONENT = "component";
+    private static final String PROP_VUE = "vue";
+
 
     private static final Pattern DEFINE_COMPONENT_NAME = Pattern.compile(
             "export\\s+default\\s+defineComponent\\s*\\(\\s*\\{[^}]*?name\\s*:\\s*['\"]([\\w]+)['\"]",
@@ -49,7 +53,7 @@ public String getName() {
 
     @Override
     public Set<String> getSupportedLanguages() {
-        return Set.of("typescript", "javascript", "vue");
+        return Set.of("typescript", "javascript", PROP_VUE);
     }
 
     @Override
@@ -68,9 +72,9 @@ public DetectorResult detect(DetectorContext ctx) {
         while (m.find()) {
             String name = m.group(1);
             if (componentNames.contains(name)) continue;
-            CodeNode node = FrontendDetectorHelper.createComponentNode("vue", filePath, "component",
+            CodeNode node = FrontendDetectorHelper.createComponentNode(PROP_VUE, filePath, PROP_COMPONENT,
                     name, NodeKind.COMPONENT, FrontendDetectorHelper.lineAt(text, m.start()));
-            node.getProperties().put("api_style", "composition");
+            node.getProperties().put(PROP_API_STYLE, "composition");
             nodes.add(node);
             componentNames.add(name);
         }
@@ -80,9 +84,9 @@ public DetectorResult detect(DetectorContext ctx) {
         while (m.find()) {
             String name = m.group(1);
             if (componentNames.contains(name)) continue;
-            CodeNode node = FrontendDetectorHelper.createComponentNode("vue", filePath, "component",
+            CodeNode node = FrontendDetectorHelper.createComponentNode(PROP_VUE, filePath, PROP_COMPONENT,
                     name, NodeKind.COMPONENT, FrontendDetectorHelper.lineAt(text, m.start()));
-            node.getProperties().put("api_style", "options");
+            node.getProperties().put(PROP_API_STYLE, "options");
             nodes.add(node);
             componentNames.add(name);
         }
@@ -92,9 +96,9 @@ public DetectorResult detect(DetectorContext ctx) {
         while (m.find()) {
             String compName = extractScriptSetupName(filePath);
             if (compName == null || componentNames.contains(compName)) continue;
-            CodeNode node = FrontendDetectorHelper.createComponentNode("vue", filePath, "component",
+            CodeNode node = FrontendDetectorHelper.createComponentNode(PROP_VUE, filePath, PROP_COMPONENT,
                     compName, NodeKind.COMPONENT, FrontendDetectorHelper.lineAt(text, m.start()));
-            node.getProperties().put("api_style", "script_setup");
+            node.getProperties().put(PROP_API_STYLE, "script_setup");
             nodes.add(node);
             componentNames.add(compName);
         }
@@ -106,7 +110,7 @@ public DetectorResult detect(DetectorContext ctx) {
             while (hm.find()) {
                 String name = hm.group(1);
                 if (hookNames.contains(name)) continue;
-                nodes.add(FrontendDetectorHelper.createComponentNode("vue", filePath, "hook",
+                nodes.add(FrontendDetectorHelper.createComponentNode(PROP_VUE, filePath, "hook",
                         name, NodeKind.HOOK, FrontendDetectorHelper.lineAt(text, hm.start())));
                 hookNames.add(name);
             }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/go/GoOrmDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/go/GoOrmDetector.java
index f0e0d4a2..ad675b26 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/go/GoOrmDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/go/GoOrmDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.go;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeEdge;
@@ -30,6 +29,13 @@
 )
 @Component
 public class GoOrmDetector extends AbstractAntlrDetector {
+    private static final String PROP_DATABASE_SQL = "database_sql";
+    private static final String PROP_FRAMEWORK = "framework";
+    private static final String PROP_GORM = "gorm";
+    private static final String PROP_OP = "op";
+    private static final String PROP_OPERATION = "operation";
+    private static final String PROP_SQLX = "sqlx";
+
 
     private static final Pattern GORM_MODEL_RE = Pattern.compile("type\\s+(?<name>\\w+)\\s+struct\\s*\\{[^}]*gorm\\.Model", Pattern.DOTALL);
     private static final Pattern GORM_MIGRATE_RE = Pattern.compile("\\.AutoMigrate\\s*\\(", Pattern.MULTILINE);
@@ -53,9 +59,9 @@ public Set<String> getSupportedLanguages() {
     }
 
     private static String detectOrm(String text) {
-        if (HAS_GORM_RE.matcher(text).find()) return "gorm";
-        if (HAS_SQLX_RE.matcher(text).find()) return "sqlx";
-        if (HAS_DATABASE_SQL_RE.matcher(text).find()) return "database_sql";
+        if (HAS_GORM_RE.matcher(text).find()) return PROP_GORM;
+        if (HAS_SQLX_RE.matcher(text).find()) return PROP_SQLX;
+        if (HAS_DATABASE_SQL_RE.matcher(text).find()) return PROP_DATABASE_SQL;
         return null;
     }
     @Override
@@ -87,7 +93,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFqn(filePath + "::" + modelName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "gorm");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_GORM);
             node.getProperties().put("type", "model");
             nodes.add(node);
         }
@@ -103,7 +109,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFqn(filePath + "::AutoMigrate");
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "gorm");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_GORM);
             node.getProperties().put("type", "auto_migrate");
             nodes.add(node);
         }
@@ -112,7 +118,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
         if ("gorm".equals(orm)) {
             m = GORM_QUERY_RE.matcher(text);
             while (m.find()) {
-                String op = m.group("op");
+                String op = m.group(PROP_OP);
                 int line = findLineNumber(text, m.start());
                 String sourceId = "go_orm:" + filePath + ":query:" + op + ":" + line;
                 CodeEdge edge = new CodeEdge();
@@ -120,8 +126,8 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 edge.setKind(EdgeKind.QUERIES);
                 edge.setSourceId(filePath);
                 edge.setTarget(new CodeNode(sourceId, NodeKind.QUERY, "gorm." + op));
-                edge.getProperties().put("framework", "gorm");
-                edge.getProperties().put("operation", op);
+                edge.getProperties().put(PROP_FRAMEWORK, PROP_GORM);
+                edge.getProperties().put(PROP_OPERATION, op);
                 edges.add(edge);
             }
         }
@@ -129,7 +135,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
         // sqlx connections
         m = SQLX_CONNECT_RE.matcher(text);
         while (m.find()) {
-            String op = m.group("op");
+            String op = m.group(PROP_OP);
             int line = findLineNumber(text, m.start());
             CodeNode node = new CodeNode();
             node.setId("go_orm:" + filePath + ":connection:sqlx:" + line);
@@ -138,8 +144,8 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFqn(filePath + "::sqlx." + op);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "sqlx");
-            node.getProperties().put("operation", op);
+            node.getProperties().put(PROP_FRAMEWORK, PROP_SQLX);
+            node.getProperties().put(PROP_OPERATION, op);
             nodes.add(node);
         }
 
@@ -147,7 +153,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
         if ("sqlx".equals(orm)) {
             m = SQLX_QUERY_RE.matcher(text);
             while (m.find()) {
-                String op = m.group("op");
+                String op = m.group(PROP_OP);
                 int line = findLineNumber(text, m.start());
                 String targetId = "go_orm:" + filePath + ":query:sqlx:" + op + ":" + line;
                 CodeEdge edge = new CodeEdge();
@@ -155,8 +161,8 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 edge.setKind(EdgeKind.QUERIES);
                 edge.setSourceId(filePath);
                 edge.setTarget(new CodeNode(targetId, NodeKind.QUERY, "sqlx." + op));
-                edge.getProperties().put("framework", "sqlx");
-                edge.getProperties().put("operation", op);
+                edge.getProperties().put(PROP_FRAMEWORK, PROP_SQLX);
+                edge.getProperties().put(PROP_OPERATION, op);
                 edges.add(edge);
             }
         }
@@ -172,8 +178,8 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFqn(filePath + "::sql.Open");
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "database_sql");
-            node.getProperties().put("operation", "Open");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_DATABASE_SQL);
+            node.getProperties().put(PROP_OPERATION, "Open");
             nodes.add(node);
         }
 
@@ -181,7 +187,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
         if ("database_sql".equals(orm)) {
             m = SQL_QUERY_RE.matcher(text);
             while (m.find()) {
-                String op = m.group("op");
+                String op = m.group(PROP_OP);
                 int line = findLineNumber(text, m.start());
                 String targetId = "go_orm:" + filePath + ":query:sql:" + op + ":" + line;
                 CodeEdge edge = new CodeEdge();
@@ -189,8 +195,8 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 edge.setKind(EdgeKind.QUERIES);
                 edge.setSourceId(filePath);
                 edge.setTarget(new CodeNode(targetId, NodeKind.QUERY, "sql." + op));
-                edge.getProperties().put("framework", "database_sql");
-                edge.getProperties().put("operation", op);
+                edge.getProperties().put(PROP_FRAMEWORK, PROP_DATABASE_SQL);
+                edge.getProperties().put(PROP_OPERATION, op);
                 edges.add(edge);
             }
         }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/go/GoStructuresDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/go/GoStructuresDetector.java
index 647b8380..b940cef3 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/go/GoStructuresDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/go/GoStructuresDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.go;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeEdge;
@@ -27,6 +26,8 @@
 )
 @Component
 public class GoStructuresDetector extends AbstractAntlrDetector {
+    private static final String PROP_EXPORTED = "exported";
+
 
     private static final Pattern STRUCT_RE = Pattern.compile("type\\s+(\\w+)\\s+struct\\s*\\{");
     private static final Pattern INTERFACE_RE = Pattern.compile("type\\s+(\\w+)\\s+interface\\s*\\{");
@@ -115,7 +116,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFqn(pkgName != null ? pkgName + "." + name : name);
             node.setFilePath(filePath);
             node.setLineStart(findLineNumber(text, sm.start()));
-            node.getProperties().put("exported", exported);
+            node.getProperties().put(PROP_EXPORTED, exported);
             node.getProperties().put("type", "struct");
             nodes.add(node);
         }
@@ -132,7 +133,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFqn(pkgName != null ? pkgName + "." + name : name);
             node.setFilePath(filePath);
             node.setLineStart(findLineNumber(text, ifm.start()));
-            node.getProperties().put("exported", exported);
+            node.getProperties().put(PROP_EXPORTED, exported);
             nodes.add(node);
         }
 
@@ -151,7 +152,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFqn(pkgName != null ? pkgName + "." + receiver + "." + methodName : receiver + "." + methodName);
             node.setFilePath(filePath);
             node.setLineStart(findLineNumber(text, mm.start()));
-            node.getProperties().put("exported", exported);
+            node.getProperties().put(PROP_EXPORTED, exported);
             node.getProperties().put("receiver_type", receiver);
             nodes.add(node);
 
@@ -181,7 +182,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFqn(pkgName != null ? pkgName + "." + funcName : funcName);
             node.setFilePath(filePath);
             node.setLineStart(findLineNumber(text, fm.start()));
-            node.getProperties().put("exported", exported);
+            node.getProperties().put(PROP_EXPORTED, exported);
             node.getProperties().put("type", "function");
             nodes.add(node);
         }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/go/GoWebDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/go/GoWebDetector.java
index f082c149..2be22027 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/go/GoWebDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/go/GoWebDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.go;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeNode;
@@ -25,6 +24,10 @@
 )
 @Component
 public class GoWebDetector extends AbstractAntlrDetector {
+    private static final String PROP_METHOD = "method";
+    private static final String PROP_MUX = "mux";
+    private static final String PROP_PATH = "path";
+
 
     private static final Pattern UPPER_ROUTE_RE = Pattern.compile("\\.(?<method>GET|POST|PUT|DELETE|PATCH|HEAD|OPTIONS)\\s*\\(\\s*\"(?<path>[^\"]*)\"", Pattern.MULTILINE);
     private static final Pattern LOWER_ROUTE_RE = Pattern.compile("\\.(?<method>Get|Post|Put|Delete|Patch|Head|Options)\\s*\\(\\s*\"(?<path>[^\"]*)\"", Pattern.MULTILINE);
@@ -51,7 +54,7 @@ private static String detectFramework(String text) {
         if (GIN_RE.matcher(text).find()) return "gin";
         if (ECHO_RE.matcher(text).find()) return "echo";
         if (CHI_RE.matcher(text).find()) return "chi";
-        if (MUX_RE.matcher(text).find()) return "mux";
+        if (MUX_RE.matcher(text).find()) return PROP_MUX;
         return "net_http";
     }
     @Override
@@ -73,8 +76,8 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
         // Gin/Echo uppercase routes
         Matcher m = UPPER_ROUTE_RE.matcher(text);
         while (m.find()) {
-            String method = m.group("method");
-            String path = m.group("path");
+            String method = m.group(PROP_METHOD);
+            String path = m.group(PROP_PATH);
             int line = findLineNumber(text, m.start());
             nodes.add(endpointNode(filePath, method, path, line, framework));
         }
@@ -82,8 +85,8 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
         // Chi lowercase routes
         m = LOWER_ROUTE_RE.matcher(text);
         while (m.find()) {
-            String method = m.group("method").toUpperCase();
-            String path = m.group("path");
+            String method = m.group(PROP_METHOD).toUpperCase();
+            String path = m.group(PROP_PATH);
             int line = findLineNumber(text, m.start());
             nodes.add(endpointNode(filePath, method, path, line, "chi"));
         }
@@ -92,10 +95,10 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
         Set<Integer> handleFuncWithMethodPositions = new HashSet<>();
         m = HANDLEFUNC_RE.matcher(text);
         while (m.find()) {
-            String method = m.group("method");
-            String path = m.group("path");
+            String method = m.group(PROP_METHOD);
+            String path = m.group(PROP_PATH);
             int line = findLineNumber(text, m.start());
-            nodes.add(endpointNode(filePath, method, path, line, "mux"));
+            nodes.add(endpointNode(filePath, method, path, line, PROP_MUX));
             handleFuncWithMethodPositions.add(m.start());
         }
 
@@ -104,16 +107,16 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             m = HANDLEFUNC_NO_METHOD_RE.matcher(text);
             while (m.find()) {
                 if (handleFuncWithMethodPositions.contains(m.start())) continue;
-                String path = m.group("path");
+                String path = m.group(PROP_PATH);
                 int line = findLineNumber(text, m.start());
-                nodes.add(endpointNode(filePath, "ANY", path, line, "mux"));
+                nodes.add(endpointNode(filePath, "ANY", path, line, PROP_MUX));
             }
         }
 
         // net/http Handle/HandleFunc
         m = HTTP_HANDLE_RE.matcher(text);
         while (m.find()) {
-            String path = m.group("path");
+            String path = m.group(PROP_PATH);
             int line = findLineNumber(text, m.start());
             nodes.add(endpointNode(filePath, "ANY", path, line, "net_http"));
         }
@@ -148,7 +151,7 @@ private static CodeNode endpointNode(String filePath, String method, String path
         node.setLineStart(line);
         node.getProperties().put("framework", fw);
         node.getProperties().put("http_method", method);
-        node.getProperties().put("path", path);
+        node.getProperties().put(PROP_PATH, path);
         return node;
     }
 }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/iac/TerraformDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/iac/TerraformDetector.java
index 09cf468a..2f0f8da7 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/iac/TerraformDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/iac/TerraformDetector.java
@@ -27,6 +27,9 @@
 )
 @Component
 public class TerraformDetector extends AbstractRegexDetector {
+    private static final String PROP_PROVIDER = "provider";
+    private static final String PROP_RESOURCE_TYPE = "resource_type";
+
 
     private static final Pattern RESOURCE_RE = Pattern.compile("resource\\s+\"([^\"]+)\"\\s+\"([^\"]+)\"");
     private static final Pattern DATA_RE = Pattern.compile("data\\s+\"([^\"]+)\"\\s+\"([^\"]+)\"");
@@ -58,8 +61,8 @@ public DetectorResult detect(DetectorContext ctx) {
             n.setKind(NodeKind.INFRA_RESOURCE); n.setLabel(resourceType + "." + resourceName);
             n.setFqn(resourceType + "." + resourceName); n.setFilePath(ctx.filePath());
             n.setLineStart(findLineNumber(text, m.start()));
-            n.getProperties().put("resource_type", resourceType);
-            if (provider != null) n.getProperties().put("provider", provider);
+            n.getProperties().put(PROP_RESOURCE_TYPE, resourceType);
+            if (provider != null) n.getProperties().put(PROP_PROVIDER, provider);
             nodes.add(n);
         }
 
@@ -71,8 +74,8 @@ public DetectorResult detect(DetectorContext ctx) {
             n.setKind(NodeKind.INFRA_RESOURCE); n.setLabel("data." + dataType + "." + dataName);
             n.setFqn("data." + dataType + "." + dataName); n.setFilePath(ctx.filePath());
             n.setLineStart(findLineNumber(text, m.start()));
-            n.getProperties().put("resource_type", dataType); n.getProperties().put("data_source", true);
-            if (provider != null) n.getProperties().put("provider", provider);
+            n.getProperties().put(PROP_RESOURCE_TYPE, dataType); n.getProperties().put("data_source", true);
+            if (provider != null) n.getProperties().put(PROP_PROVIDER, provider);
             nodes.add(n);
         }
 
@@ -119,7 +122,7 @@ public DetectorResult detect(DetectorContext ctx) {
             n.setKind(NodeKind.INFRA_RESOURCE); n.setLabel("provider." + m.group(1));
             n.setFqn("provider." + m.group(1)); n.setFilePath(ctx.filePath());
             n.setLineStart(findLineNumber(text, m.start()));
-            n.getProperties().put("resource_type", "provider"); n.getProperties().put("provider", m.group(1));
+            n.getProperties().put(PROP_RESOURCE_TYPE, PROP_PROVIDER); n.getProperties().put(PROP_PROVIDER, m.group(1));
             nodes.add(n);
         }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/AzureFunctionsDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/AzureFunctionsDetector.java
index 198a6cff..55fa00e1 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/AzureFunctionsDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/AzureFunctionsDetector.java
@@ -28,6 +28,9 @@
 )
 @Component
 public class AzureFunctionsDetector extends AbstractRegexDetector {
+    private static final String PROP_BROKER = "broker";
+    private static final String PROP_TRIGGER_TYPE = "trigger_type";
+
 
     private static final Pattern FUNCTION_NAME_RE = Pattern.compile("@FunctionName\\s*\\(\\s*\"([^\"]+)\"");
     private static final Pattern HTTP_TRIGGER_RE = Pattern.compile("@HttpTrigger\\s*\\(");
@@ -79,7 +82,7 @@ public DetectorResult detect(DetectorContext ctx) {
             Map<String, Object> props = new LinkedHashMap<>();
 
             if (HTTP_TRIGGER_RE.matcher(contextLines).find()) {
-                props.put("trigger_type", "http");
+                props.put(PROP_TRIGGER_TYPE, "http");
                 nodes.add(funcNode(funcNodeId, funcName, className, i + 1, ctx,
                         List.of("@FunctionName", "@HttpTrigger"), props));
 
@@ -102,14 +105,14 @@ public DetectorResult detect(DetectorContext ctx) {
             Matcher sbq = SB_QUEUE_RE.matcher(contextLines);
             if (sbq.find()) {
                 String queueName = sbq.group(1);
-                props.put("trigger_type", "serviceBusQueue");
+                props.put(PROP_TRIGGER_TYPE, "serviceBusQueue");
                 props.put("queue_name", queueName);
                 nodes.add(funcNode(funcNodeId, funcName, className, i + 1, ctx,
                         List.of("@FunctionName", "@ServiceBusQueueTrigger"), props));
 
                 String queueNodeId = "azure:servicebus:queue:" + queueName;
                 CodeNode qNode = new CodeNode(queueNodeId, NodeKind.QUEUE, "servicebus:" + queueName);
-                qNode.getProperties().put("broker", "azure_servicebus");
+                qNode.getProperties().put(PROP_BROKER, "azure_servicebus");
                 qNode.getProperties().put("queue", queueName);
                 nodes.add(qNode);
                 addEdge(queueNodeId, funcNodeId, EdgeKind.TRIGGERS,
@@ -120,14 +123,14 @@ public DetectorResult detect(DetectorContext ctx) {
             Matcher sbt = SB_TOPIC_RE.matcher(contextLines);
             if (sbt.find()) {
                 String topicName = sbt.group(1);
-                props.put("trigger_type", "serviceBusTopic");
+                props.put(PROP_TRIGGER_TYPE, "serviceBusTopic");
                 props.put("topic_name", topicName);
                 nodes.add(funcNode(funcNodeId, funcName, className, i + 1, ctx,
                         List.of("@FunctionName", "@ServiceBusTopicTrigger"), props));
 
                 String topicNodeId = "azure:servicebus:topic:" + topicName;
                 CodeNode tNode = new CodeNode(topicNodeId, NodeKind.TOPIC, "servicebus:" + topicName);
-                tNode.getProperties().put("broker", "azure_servicebus");
+                tNode.getProperties().put(PROP_BROKER, "azure_servicebus");
                 tNode.getProperties().put("topic", topicName);
                 nodes.add(tNode);
                 addEdge(topicNodeId, funcNodeId, EdgeKind.TRIGGERS,
@@ -138,14 +141,14 @@ public DetectorResult detect(DetectorContext ctx) {
             Matcher ehm = EH_TRIGGER_RE.matcher(contextLines);
             if (ehm.find()) {
                 String hubName = ehm.group(1);
-                props.put("trigger_type", "eventHub");
+                props.put(PROP_TRIGGER_TYPE, "eventHub");
                 props.put("event_hub_name", hubName);
                 nodes.add(funcNode(funcNodeId, funcName, className, i + 1, ctx,
                         List.of("@FunctionName", "@EventHubTrigger"), props));
 
                 String hubNodeId = "azure:eventhub:" + hubName;
                 CodeNode hNode = new CodeNode(hubNodeId, NodeKind.TOPIC, "eventhub:" + hubName);
-                hNode.getProperties().put("broker", "azure_eventhub");
+                hNode.getProperties().put(PROP_BROKER, "azure_eventhub");
                 hNode.getProperties().put("event_hub", hubName);
                 nodes.add(hNode);
                 addEdge(hubNodeId, funcNodeId, EdgeKind.TRIGGERS,
@@ -156,7 +159,7 @@ public DetectorResult detect(DetectorContext ctx) {
             Matcher tm = TIMER_RE.matcher(contextLines);
             if (tm.find()) {
                 String schedule = tm.group(1);
-                props.put("trigger_type", "timer");
+                props.put(PROP_TRIGGER_TYPE, "timer");
                 props.put("schedule", schedule);
                 nodes.add(funcNode(funcNodeId, funcName, className, i + 1, ctx,
                         List.of("@FunctionName", "@TimerTrigger"), props));
@@ -164,7 +167,7 @@ public DetectorResult detect(DetectorContext ctx) {
             }
 
             if (COSMOS_TRIGGER_RE.matcher(contextLines).find()) {
-                props.put("trigger_type", "cosmosDB");
+                props.put(PROP_TRIGGER_TYPE, "cosmosDB");
                 nodes.add(funcNode(funcNodeId, funcName, className, i + 1, ctx,
                         List.of("@FunctionName", "@CosmosDBTrigger"), props));
 
@@ -178,7 +181,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 continue;
             }
 
-            props.put("trigger_type", "unknown");
+            props.put(PROP_TRIGGER_TYPE, "unknown");
             nodes.add(funcNode(funcNodeId, funcName, className, i + 1, ctx,
                     List.of("@FunctionName"), props));
         }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/AzureMessagingDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/AzureMessagingDetector.java
index 2216ba3d..386d4b78 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/AzureMessagingDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/AzureMessagingDetector.java
@@ -28,6 +28,14 @@
 )
 @Component
 public class AzureMessagingDetector extends AbstractRegexDetector {
+    private static final String PROP_AZURE_EVENTHUB = "azure_eventhub";
+    private static final String PROP_AZURE_SERVICEBUS = "azure_servicebus";
+    private static final String PROP_BROKER = "broker";
+    private static final String PROP_EVENT_HUB = "event_hub";
+    private static final String PROP_QUEUE = "queue";
+    private static final String PROP_ROLE = "role";
+    private static final String PROP_TOPIC = "topic";
+
 
     private static final Pattern CLASS_RE = Pattern.compile("(?:public\\s+)?class\\s+(\\w+)");
     private static final Pattern SB_SENDER_CLIENT_RE = Pattern.compile("\\bServiceBusSenderClient\\b");
@@ -102,53 +110,53 @@ public DetectorResult detect(DetectorContext ctx) {
         for (String qname : queueNames) {
             String queueId = ensureSbQueueNode(qname, seenSbQueues, nodes);
             if (isSbSender) addMessagingEdge(classNodeId, queueId, EdgeKind.SENDS_TO,
-                    className + " sends to " + qname, Map.of("queue", qname), edges);
+                    className + " sends to " + qname, Map.of(PROP_QUEUE, qname), edges);
             if (isSbReceiver) addMessagingEdge(classNodeId, queueId, EdgeKind.RECEIVES_FROM,
-                    className + " receives from " + qname, Map.of("queue", qname), edges);
+                    className + " receives from " + qname, Map.of(PROP_QUEUE, qname), edges);
         }
 
         for (String tname : topicNames) {
             String topicId = ensureSbTopicNode(tname, seenSbTopics, nodes);
             if (isSbSender) addMessagingEdge(classNodeId, topicId, EdgeKind.SENDS_TO,
-                    className + " sends to " + tname, Map.of("topic", tname), edges);
+                    className + " sends to " + tname, Map.of(PROP_TOPIC, tname), edges);
             if (isSbReceiver) addMessagingEdge(classNodeId, topicId, EdgeKind.RECEIVES_FROM,
-                    className + " receives from " + tname, Map.of("topic", tname), edges);
+                    className + " receives from " + tname, Map.of(PROP_TOPIC, tname), edges);
         }
 
         for (String ehname : ehNames) {
             String ehId = ensureEventhubNode(ehname, seenEventHubs, nodes);
             if (isEhProducer) addMessagingEdge(classNodeId, ehId, EdgeKind.SENDS_TO,
-                    className + " sends to " + ehname, Map.of("event_hub", ehname), edges);
+                    className + " sends to " + ehname, Map.of(PROP_EVENT_HUB, ehname), edges);
             if (isEhConsumer) addMessagingEdge(classNodeId, ehId, EdgeKind.RECEIVES_FROM,
-                    className + " receives from " + ehname, Map.of("event_hub", ehname), edges);
+                    className + " receives from " + ehname, Map.of(PROP_EVENT_HUB, ehname), edges);
         }
 
         // Generic fallbacks
         if (isSbSender && queueNames.isEmpty() && topicNames.isEmpty()) {
             nodes.add(genericNode("azure:servicebus:__sender__", NodeKind.QUEUE, "azure:servicebus:sender",
-                    Map.of("broker", "azure_servicebus", "role", "sender")));
+                    Map.of(PROP_BROKER, PROP_AZURE_SERVICEBUS, PROP_ROLE, "sender")));
             addMessagingEdge(classNodeId, "azure:servicebus:__sender__", EdgeKind.SENDS_TO,
                     className + " sends to Azure Service Bus", Map.of(), edges);
         } else if (isSbReceiver && queueNames.isEmpty() && topicNames.isEmpty()) {
             nodes.add(genericNode("azure:servicebus:__receiver__", NodeKind.QUEUE, "azure:servicebus:receiver",
-                    Map.of("broker", "azure_servicebus", "role", "receiver")));
+                    Map.of(PROP_BROKER, PROP_AZURE_SERVICEBUS, PROP_ROLE, "receiver")));
             addMessagingEdge(classNodeId, "azure:servicebus:__receiver__", EdgeKind.RECEIVES_FROM,
                     className + " receives from Azure Service Bus", Map.of(), edges);
         } else if (hasSbClient && queueNames.isEmpty() && topicNames.isEmpty() && !isSbSender && !isSbReceiver) {
             nodes.add(genericNode("azure:servicebus:__client__", NodeKind.QUEUE, "azure:servicebus:client",
-                    Map.of("broker", "azure_servicebus", "role", "client")));
+                    Map.of(PROP_BROKER, PROP_AZURE_SERVICEBUS, PROP_ROLE, "client")));
             addMessagingEdge(classNodeId, "azure:servicebus:__client__", EdgeKind.CONNECTS_TO,
                     className + " connects to Azure Service Bus", Map.of(), edges);
         }
 
         if (isEhProducer && ehNames.isEmpty()) {
             nodes.add(genericNode("azure:eventhub:__producer__", NodeKind.TOPIC, "azure:eventhub:producer",
-                    Map.of("broker", "azure_eventhub", "role", "producer")));
+                    Map.of(PROP_BROKER, PROP_AZURE_EVENTHUB, PROP_ROLE, "producer")));
             addMessagingEdge(classNodeId, "azure:eventhub:__producer__", EdgeKind.SENDS_TO,
                     className + " sends to Azure Event Hub", Map.of(), edges);
         } else if (isEhConsumer && ehNames.isEmpty()) {
             nodes.add(genericNode("azure:eventhub:__consumer__", NodeKind.TOPIC, "azure:eventhub:consumer",
-                    Map.of("broker", "azure_eventhub", "role", "consumer")));
+                    Map.of(PROP_BROKER, PROP_AZURE_EVENTHUB, PROP_ROLE, "consumer")));
             addMessagingEdge(classNodeId, "azure:eventhub:__consumer__", EdgeKind.RECEIVES_FROM,
                     className + " receives from Azure Event Hub", Map.of(), edges);
         }
@@ -161,7 +169,7 @@ private String ensureSbQueueNode(String name, Set<String> seen, List<CodeNode> n
         if (!seen.contains(name)) {
             seen.add(name);
             nodes.add(genericNode(nodeId, NodeKind.QUEUE, "azure:servicebus:" + name,
-                    Map.of("broker", "azure_servicebus", "queue", name)));
+                    Map.of(PROP_BROKER, PROP_AZURE_SERVICEBUS, PROP_QUEUE, name)));
         }
         return nodeId;
     }
@@ -171,7 +179,7 @@ private String ensureSbTopicNode(String name, Set<String> seen, List<CodeNode> n
         if (!seen.contains(name)) {
             seen.add(name);
             nodes.add(genericNode(nodeId, NodeKind.TOPIC, "azure:servicebus:" + name,
-                    Map.of("broker", "azure_servicebus", "topic", name)));
+                    Map.of(PROP_BROKER, PROP_AZURE_SERVICEBUS, PROP_TOPIC, name)));
         }
         return nodeId;
     }
@@ -181,7 +189,7 @@ private String ensureEventhubNode(String name, Set<String> seen, List<CodeNode>
         if (!seen.contains(name)) {
             seen.add(name);
             nodes.add(genericNode(nodeId, NodeKind.TOPIC, "azure:eventhub:" + name,
-                    Map.of("broker", "azure_eventhub", "event_hub", name)));
+                    Map.of(PROP_BROKER, PROP_AZURE_EVENTHUB, PROP_EVENT_HUB, name)));
         }
         return nodeId;
     }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/ClassHierarchyDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/ClassHierarchyDetector.java
index 8ba6fed1..279f6e9f 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/ClassHierarchyDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/ClassHierarchyDetector.java
@@ -34,6 +34,13 @@
 )
 @Component
 public class ClassHierarchyDetector extends AbstractJavaParserDetector {
+    private static final String PROP_PROTECTED = "protected";
+
+
+    private static final String PROP_INTERFACES = "interfaces";
+    private static final String PROP_IS_ABSTRACT = "is_abstract";
+    private static final String PROP_IS_FINAL = "is_final";
+    private static final String PROP_VISIBILITY = "visibility";
 
     // ---- Regex patterns for fallback ----
     private static final Pattern CLASS_DECL_RE = Pattern.compile(
@@ -100,9 +107,9 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
             }
 
             Map<String, Object> props = new LinkedHashMap<>();
-            props.put("visibility", visibility);
-            props.put("is_abstract", isAbstract);
-            props.put("is_final", isFinal);
+            props.put(PROP_VISIBILITY, visibility);
+            props.put(PROP_IS_ABSTRACT, isAbstract);
+            props.put(PROP_IS_FINAL, isFinal);
 
             // Extended types
             List<String> extendedTypes = new ArrayList<>();
@@ -111,7 +118,7 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
             }
             if (!extendedTypes.isEmpty()) {
                 if (isInterface) {
-                    props.put("interfaces", extendedTypes);
+                    props.put(PROP_INTERFACES, extendedTypes);
                 } else {
                     props.put("superclass", extendedTypes.get(0));
                 }
@@ -123,7 +130,7 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
                 implementedTypes.add(impl.getNameAsString());
             }
             if (!implementedTypes.isEmpty()) {
-                props.put("interfaces", implementedTypes);
+                props.put(PROP_INTERFACES, implementedTypes);
             }
 
             CodeNode node = new CodeNode();
@@ -179,7 +186,7 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
             int lineEnd = decl.getEnd().map(p -> p.line).orElse(line);
 
             String visibility = decl.isPublic() ? "public"
-                    : decl.isProtected() ? "protected"
+                    : decl.isProtected() ? PROP_PROTECTED
                     : decl.isPrivate() ? "private"
                     : "package-private";
 
@@ -189,10 +196,10 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
             }
 
             Map<String, Object> props = new LinkedHashMap<>();
-            props.put("visibility", visibility);
-            props.put("is_abstract", false);
-            props.put("is_final", false);
-            if (!interfaces.isEmpty()) props.put("interfaces", interfaces);
+            props.put(PROP_VISIBILITY, visibility);
+            props.put(PROP_IS_ABSTRACT, false);
+            props.put(PROP_IS_FINAL, false);
+            if (!interfaces.isEmpty()) props.put(PROP_INTERFACES, interfaces);
 
             CodeNode node = new CodeNode();
             node.setId(nodeId);
@@ -224,14 +231,14 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
             int lineEnd = decl.getEnd().map(p -> p.line).orElse(line);
 
             String visibility = decl.isPublic() ? "public"
-                    : decl.isProtected() ? "protected"
+                    : decl.isProtected() ? PROP_PROTECTED
                     : decl.isPrivate() ? "private"
                     : "package-private";
 
             Map<String, Object> props = new LinkedHashMap<>();
-            props.put("visibility", visibility);
-            props.put("is_abstract", false);
-            props.put("is_final", false);
+            props.put(PROP_VISIBILITY, visibility);
+            props.put(PROP_IS_ABSTRACT, false);
+            props.put(PROP_IS_FINAL, false);
 
             CodeNode node = new CodeNode();
             node.setId(nodeId);
@@ -250,7 +257,7 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
 
     private String resolveVisibility(ClassOrInterfaceDeclaration decl) {
         if (decl.isPublic()) return "public";
-        if (decl.isProtected()) return "protected";
+        if (decl.isProtected()) return PROP_PROTECTED;
         if (decl.isPrivate()) return "private";
         return "package-private";
     }
@@ -278,11 +285,11 @@ private DetectorResult detectWithRegex(DetectorContext ctx) {
                 NodeKind kind = isAbstract ? NodeKind.ABSTRACT_CLASS : NodeKind.CLASS;
 
                 Map<String, Object> props = new LinkedHashMap<>();
-                props.put("visibility", visibility);
-                props.put("is_abstract", isAbstract);
-                props.put("is_final", isFinal);
+                props.put(PROP_VISIBILITY, visibility);
+                props.put(PROP_IS_ABSTRACT, isAbstract);
+                props.put(PROP_IS_FINAL, isFinal);
                 if (superclass != null) props.put("superclass", superclass);
-                if (!interfaces.isEmpty()) props.put("interfaces", interfaces);
+                if (!interfaces.isEmpty()) props.put(PROP_INTERFACES, interfaces);
 
                 CodeNode node = new CodeNode();
                 node.setId(nodeId);
@@ -322,10 +329,10 @@ private DetectorResult detectWithRegex(DetectorContext ctx) {
 
                 String nodeId = ctx.filePath() + ":" + name;
                 Map<String, Object> props = new LinkedHashMap<>();
-                props.put("visibility", visibility);
-                props.put("is_abstract", false);
-                props.put("is_final", false);
-                if (!extended.isEmpty()) props.put("interfaces", extended);
+                props.put(PROP_VISIBILITY, visibility);
+                props.put(PROP_IS_ABSTRACT, false);
+                props.put(PROP_IS_FINAL, false);
+                if (!extended.isEmpty()) props.put(PROP_INTERFACES, extended);
 
                 CodeNode node = new CodeNode();
                 node.setId(nodeId);
@@ -357,10 +364,10 @@ private DetectorResult detectWithRegex(DetectorContext ctx) {
 
                 String nodeId = ctx.filePath() + ":" + name;
                 Map<String, Object> props = new LinkedHashMap<>();
-                props.put("visibility", visibility);
-                props.put("is_abstract", false);
-                props.put("is_final", false);
-                if (!interfaces.isEmpty()) props.put("interfaces", interfaces);
+                props.put(PROP_VISIBILITY, visibility);
+                props.put(PROP_IS_ABSTRACT, false);
+                props.put(PROP_IS_FINAL, false);
+                if (!interfaces.isEmpty()) props.put(PROP_INTERFACES, interfaces);
 
                 CodeNode node = new CodeNode();
                 node.setId(nodeId);
@@ -391,9 +398,9 @@ private DetectorResult detectWithRegex(DetectorContext ctx) {
 
                 String nodeId = ctx.filePath() + ":" + name;
                 Map<String, Object> props = new LinkedHashMap<>();
-                props.put("visibility", visibility);
-                props.put("is_abstract", false);
-                props.put("is_final", false);
+                props.put(PROP_VISIBILITY, visibility);
+                props.put(PROP_IS_ABSTRACT, false);
+                props.put(PROP_IS_FINAL, false);
 
                 CodeNode node = new CodeNode();
                 node.setId(nodeId);
@@ -413,7 +420,7 @@ private DetectorResult detectWithRegex(DetectorContext ctx) {
     private String parseVisibility(String modifier) {
         if (modifier == null) return "package-private";
         String trimmed = modifier.trim();
-        if (trimmed.equals("public") || trimmed.equals("protected") || trimmed.equals("private")) {
+        if (trimmed.equals("public") || trimmed.equals(PROP_PROTECTED) || trimmed.equals("private")) {
             return trimmed;
         }
         return "package-private";
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/ConfigDefDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/ConfigDefDetector.java
index 3d776c20..6ba7d641 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/ConfigDefDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/ConfigDefDetector.java
@@ -4,10 +4,8 @@
 import com.github.javaparser.ast.body.ClassOrInterfaceDeclaration;
 import com.github.javaparser.ast.body.FieldDeclaration;
 import com.github.javaparser.ast.body.MethodDeclaration;
-import com.github.javaparser.ast.body.Parameter;
 import com.github.javaparser.ast.expr.AnnotationExpr;
 import com.github.javaparser.ast.expr.MethodCallExpr;
-import com.github.javaparser.ast.expr.StringLiteralExpr;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeEdge;
@@ -37,6 +35,9 @@
 )
 @Component
 public class ConfigDefDetector extends AbstractJavaParserDetector {
+    private static final String PROP_CONFIGDEF = "ConfigDef";
+    private static final String PROP_SPRING_VALUE = "spring_value";
+
 
     // ---- Regex fallback patterns ----
     private static final Pattern CLASS_RE = Pattern.compile("(?:public\\s+)?class\\s+(\\w+)");
@@ -62,7 +63,7 @@ public DetectorResult detect(DetectorContext ctx) {
         String text = ctx.content();
         if (text == null) return DetectorResult.empty();
 
-        boolean hasConfigDef = text.contains("ConfigDef");
+        boolean hasConfigDef = text.contains(PROP_CONFIGDEF);
         boolean hasValue = text.contains("@Value");
         boolean hasConfigProps = text.contains("@ConfigurationProperties");
 
@@ -89,7 +90,7 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
             String classNodeId = ctx.filePath() + ":" + className;
 
             // 1. Kafka ConfigDef.define() calls
-            // Discriminator: receiver must mention "ConfigDef" or "CONFIG" to avoid matching
+            // Discriminator: receiver must mention PROP_CONFIGDEF or "CONFIG" to avoid matching
             // unrelated .define() calls (per CLAUDE.md: framework detectors must have guards).
             classDecl.findAll(MethodCallExpr.class).forEach(call -> {
                 if (!"define".equals(call.getNameAsString())) return;
@@ -98,7 +99,7 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
                 boolean receiverIsConfigDef = call.getScope()
                         .map(scope -> {
                             String s = scope.toString();
-                            return s.contains("ConfigDef") || s.toUpperCase().contains("CONFIG");
+                            return s.contains(PROP_CONFIGDEF) || s.toUpperCase().contains("CONFIG");
                         })
                         .orElse(false);
                 if (!receiverIsConfigDef) return;
@@ -118,7 +119,7 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
                     extractValueKey(ann).ifPresent(key -> {
                         if (seenKeys.add(key)) {
                             int line = ann.getBegin().map(p -> p.line).orElse(1);
-                            addConfigNode(key, "spring_value", classNodeId, ctx.filePath(), line, nodes, edges);
+                            addConfigNode(key, PROP_SPRING_VALUE, classNodeId, ctx.filePath(), line, nodes, edges);
                         }
                     });
                 });
@@ -131,7 +132,7 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
                         extractValueKey(ann).ifPresent(key -> {
                             if (seenKeys.add(key)) {
                                 int line = ann.getBegin().map(p -> p.line).orElse(1);
-                                addConfigNode(key, "spring_value", classNodeId, ctx.filePath(), line, nodes, edges);
+                                addConfigNode(key, PROP_SPRING_VALUE, classNodeId, ctx.filePath(), line, nodes, edges);
                             }
                         });
                     });
@@ -225,7 +226,7 @@ private DetectorResult detectWithRegex(DetectorContext ctx) {
             while (vm.find()) {
                 String key = vm.group(1);
                 if (seenKeys.add(key)) {
-                    addConfigNode(key, "spring_value", classNodeId, ctx.filePath(), i + 1, nodes, edges);
+                    addConfigNode(key, PROP_SPRING_VALUE, classNodeId, ctx.filePath(), i + 1, nodes, edges);
                 }
             }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/IbmMqDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/IbmMqDetector.java
index 9f9f298b..786a40fa 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/IbmMqDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/IbmMqDetector.java
@@ -27,6 +27,10 @@
 )
 @Component
 public class IbmMqDetector extends AbstractJavaMessagingDetector {
+    private static final String PROP_BROKER = "broker";
+    private static final String PROP_IBM_MQ = "ibm_mq";
+    private static final String PROP_QUEUE = "queue";
+
 
     private static final Pattern QM_NEW_RE = Pattern.compile("new\\s+MQQueueManager\\s*\\(\\s*\"([^\"]+)\"");
     private static final Pattern ACCESS_QUEUE_RE = Pattern.compile("accessQueue\\s*\\(\\s*\"([^\"]+)\"");
@@ -38,7 +42,7 @@ public class IbmMqDetector extends AbstractJavaMessagingDetector {
 
     @Override
     public String getName() {
-        return "ibm_mq";
+        return PROP_IBM_MQ;
     }
 
     @Override
@@ -77,7 +81,7 @@ public DetectorResult detect(DetectorContext ctx) {
             if (m.find()) {
                 String qmName = m.group(1);
                 String qmId = ensureNode("ibmmq:qm:" + qmName, qmName, NodeKind.MESSAGE_QUEUE,
-                        "ibmmq:qm:" + qmName, Map.of("broker", "ibm_mq", "queue_manager", qmName),
+                        "ibmmq:qm:" + qmName, Map.of(PROP_BROKER, PROP_IBM_MQ, "queue_manager", qmName),
                         seenQms, nodes);
                 addMessagingEdge(classNodeId, qmId, EdgeKind.CONNECTS_TO,
                         className + " connects to queue manager " + qmName,
@@ -91,14 +95,14 @@ public DetectorResult detect(DetectorContext ctx) {
             if (m.find()) {
                 String queueName = m.group(1);
                 String queueId = ensureNode("ibmmq:queue:" + queueName, queueName, NodeKind.QUEUE,
-                        "ibmmq:queue:" + queueName, Map.of("broker", "ibm_mq", "queue", queueName),
+                        "ibmmq:queue:" + queueName, Map.of(PROP_BROKER, PROP_IBM_MQ, PROP_QUEUE, queueName),
                         seenQueues, nodes);
                 if (hasPut) addMessagingEdge(classNodeId, queueId, EdgeKind.SENDS_TO,
-                        className + " sends to " + queueName, Map.of("queue", queueName), edges);
+                        className + " sends to " + queueName, Map.of(PROP_QUEUE, queueName), edges);
                 if (hasGet) addMessagingEdge(classNodeId, queueId, EdgeKind.RECEIVES_FROM,
-                        className + " receives from " + queueName, Map.of("queue", queueName), edges);
+                        className + " receives from " + queueName, Map.of(PROP_QUEUE, queueName), edges);
                 if (!hasPut && !hasGet) addMessagingEdge(classNodeId, queueId, EdgeKind.CONNECTS_TO,
-                        className + " accesses " + queueName, Map.of("queue", queueName), edges);
+                        className + " accesses " + queueName, Map.of(PROP_QUEUE, queueName), edges);
             }
         }
 
@@ -106,11 +110,11 @@ public DetectorResult detect(DetectorContext ctx) {
         for (int i = 0; i < lines.length; i++) {
             Matcher m = JMS_CREATE_QUEUE_RE.matcher(lines[i]);
             if (m.find()) ensureNode("ibmmq:queue:" + m.group(1), m.group(1), NodeKind.QUEUE,
-                    "ibmmq:queue:" + m.group(1), Map.of("broker", "ibm_mq", "queue", m.group(1)),
+                    "ibmmq:queue:" + m.group(1), Map.of(PROP_BROKER, PROP_IBM_MQ, PROP_QUEUE, m.group(1)),
                     seenQueues, nodes);
             m = JMS_CREATE_TOPIC_RE.matcher(lines[i]);
             if (m.find()) ensureNode("ibmmq:topic:" + m.group(1), m.group(1), NodeKind.TOPIC,
-                    "ibmmq:topic:" + m.group(1), Map.of("broker", "ibm_mq", "topic", m.group(1)),
+                    "ibmmq:topic:" + m.group(1), Map.of(PROP_BROKER, PROP_IBM_MQ, "topic", m.group(1)),
                     seenTopics, nodes);
         }
 
@@ -119,7 +123,7 @@ public DetectorResult detect(DetectorContext ctx) {
             node.setId("ibmmq:topic:__unknown__");
             node.setKind(NodeKind.TOPIC);
             node.setLabel("ibmmq:topic:unknown");
-            node.getProperties().put("broker", "ibm_mq");
+            node.getProperties().put(PROP_BROKER, PROP_IBM_MQ);
             nodes.add(node);
         }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/JdbcDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/JdbcDetector.java
index 56efab65..74a739b9 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/JdbcDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/JdbcDetector.java
@@ -28,6 +28,10 @@
 )
 @Component
 public class JdbcDetector extends AbstractRegexDetector {
+    private static final String PROP_DB_TYPE = "db_type";
+    private static final String PROP_HOST = "host";
+    private static final String PROP_UNKNOWN = "unknown";
+
 
     private static final Pattern CLASS_RE = Pattern.compile("(?:public\\s+)?class\\s+(\\w+)");
     private static final Pattern DRIVER_MANAGER_RE = Pattern.compile(
@@ -94,8 +98,8 @@ public DetectorResult detect(DetectorContext ctx) {
             if (!m.find()) continue;
             String url = m.group(1);
             Map<String, String> props = parseJdbcUrl(url);
-            String dbType = props.getOrDefault("db_type", "unknown");
-            String host = props.getOrDefault("host", "unknown");
+            String dbType = props.getOrDefault(PROP_DB_TYPE, PROP_UNKNOWN);
+            String host = props.getOrDefault(PROP_HOST, PROP_UNKNOWN);
             String dbId = "db:" + dbType + ":" + host;
             ensureDbNode(dbId, dbType + "@" + host, i + 1, ctx, new LinkedHashMap<>(props), seenDbs, nodes);
             addConnectEdge(classNodeId, dbId, className + " connects to " + dbType + "@" + host, edges, nodes);
@@ -130,8 +134,8 @@ public DetectorResult detect(DetectorContext ctx) {
                 if (!m.find()) continue;
                 String url = m.group(1);
                 Map<String, String> props = parseJdbcUrl(url);
-                String dbType = props.getOrDefault("db_type", "unknown");
-                String host = props.getOrDefault("host", "unknown");
+                String dbType = props.getOrDefault(PROP_DB_TYPE, PROP_UNKNOWN);
+                String host = props.getOrDefault(PROP_HOST, PROP_UNKNOWN);
                 String dbId = "db:" + dbType + ":" + host;
                 ensureDbNode(dbId, dbType + "@" + host, i + 1, ctx, new LinkedHashMap<>(props), seenDbs, nodes);
             }
@@ -146,8 +150,8 @@ public DetectorResult detect(DetectorContext ctx) {
             while (urlMatcher.find()) {
                 String url = urlMatcher.group(1);
                 Map<String, String> props = parseJdbcUrl(url);
-                String dbType = props.getOrDefault("db_type", "unknown");
-                String host = props.getOrDefault("host", "unknown");
+                String dbType = props.getOrDefault(PROP_DB_TYPE, PROP_UNKNOWN);
+                String host = props.getOrDefault(PROP_HOST, PROP_UNKNOWN);
                 String dbId = "db:" + dbType + ":" + host;
                 ensureDbNode(dbId, dbType + "@" + host, i + 1, ctx, new LinkedHashMap<>(props), seenDbs, nodes);
                 addConnectEdge(classNodeId, dbId, className + " connects to " + dbType + "@" + host, edges, nodes);
@@ -162,9 +166,9 @@ private Map<String, String> parseJdbcUrl(String url) {
         props.put("connection_url", url);
         Matcher m = JDBC_URL_RE.matcher(url);
         if (m.find()) {
-            props.put("db_type", m.group(1));
+            props.put(PROP_DB_TYPE, m.group(1));
             if (m.group(2) != null) {
-                props.put("host", m.group(2));
+                props.put(PROP_HOST, m.group(2));
             }
         }
         return props;
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/JmsDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/JmsDetector.java
index 029c9577..a3d740f1 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/JmsDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/JmsDetector.java
@@ -27,6 +27,9 @@
 )
 @Component
 public class JmsDetector extends AbstractJavaMessagingDetector {
+    private static final String PROP_DESTINATION = "destination";
+    private static final String PROP_JMS = "jms";
+
 
     private static final Pattern JMS_LISTENER_RE = Pattern.compile(
             "@JmsListener\\s*\\(\\s*(?:.*?destination\\s*=\\s*)?\"([^\"]+)\"");
@@ -36,7 +39,7 @@ public class JmsDetector extends AbstractJavaMessagingDetector {
 
     @Override
     public String getName() {
-        return "jms";
+        return PROP_JMS;
     }
 
     @Override
@@ -68,9 +71,9 @@ public DetectorResult detect(DetectorContext ctx) {
             Matcher m = JMS_LISTENER_RE.matcher(lines[i]);
             if (!m.find()) continue;
             String destination = m.group(1);
-            String queueId = ensureQueueNode("jms", destination, seenQueues, nodes);
+            String queueId = ensureQueueNode(PROP_JMS, destination, seenQueues, nodes);
             Map<String, Object> props = new LinkedHashMap<>();
-            props.put("destination", destination);
+            props.put(PROP_DESTINATION, destination);
             Matcher cf = CONTAINER_FACTORY_RE.matcher(lines[i]);
             if (cf.find()) props.put("container_factory", cf.group(1));
             addMessagingEdge(classNodeId, queueId, EdgeKind.CONSUMES,
@@ -82,10 +85,10 @@ public DetectorResult detect(DetectorContext ctx) {
             Matcher m = JMS_SEND_RE.matcher(lines[i]);
             if (!m.find()) continue;
             String destination = m.group(1);
-            String queueId = ensureQueueNode("jms", destination, seenQueues, nodes);
+            String queueId = ensureQueueNode(PROP_JMS, destination, seenQueues, nodes);
             addMessagingEdge(classNodeId, queueId, EdgeKind.PRODUCES,
                     className + " produces to " + destination,
-                    Map.of("destination", destination), edges);
+                    Map.of(PROP_DESTINATION, destination), edges);
         }
 
         return DetectorResult.of(nodes, edges);
@@ -99,7 +102,7 @@ private String ensureQueueNode(String broker, String destination, Set<String> se
             node.setKind(NodeKind.QUEUE);
             node.setLabel(broker + ":" + destination);
             node.getProperties().put("broker", broker);
-            node.getProperties().put("destination", destination);
+            node.getProperties().put(PROP_DESTINATION, destination);
             nodes.add(node);
         }
         return queueId;
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/JpaEntityDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/JpaEntityDetector.java
index 7734c802..c6b2c8fa 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/JpaEntityDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/JpaEntityDetector.java
@@ -38,6 +38,10 @@
 )
 @Component
 public class JpaEntityDetector extends AbstractJavaParserDetector {
+    private static final String PROP_FIELD = "field";
+    private static final String PROP_NAME = "name";
+    private static final String PROP_TYPE = "type";
+
 
     private static final Set<String> RELATIONSHIP_ANNOTATIONS = Set.of(
             "OneToMany", "ManyToOne", "OneToOne", "ManyToMany");
@@ -88,7 +92,6 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
         List<CodeEdge> edges = new ArrayList<>();
 
         cu.findAll(ClassOrInterfaceDeclaration.class).forEach(classDecl -> {
-            // Only process @Entity annotated classes
             boolean isEntity = classDecl.getAnnotations().stream()
                     .anyMatch(a -> "Entity".equals(a.getNameAsString()));
             if (!isEntity) return;
@@ -96,39 +99,8 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
             String className = classDecl.getNameAsString();
             String fqn = resolveFqn(cu, className);
             int classLine = classDecl.getBegin().map(p -> p.line).orElse(1);
-
-            // Extract table name from @Table annotation
-            String tableName = className.toLowerCase();
-            for (AnnotationExpr ann : classDecl.getAnnotations()) {
-                if ("Table".equals(ann.getNameAsString())) {
-                    String name = extractAnnotationStringAttr(ann, "name");
-                    if (name == null) {
-                        // Try bare value
-                        name = extractAnnotationValue(ann);
-                    }
-                    if (name != null) tableName = name;
-                }
-            }
-
-            // Extract columns from fields
-            List<Map<String, String>> columns = new ArrayList<>();
-            for (FieldDeclaration field : classDecl.getFields()) {
-                for (VariableDeclarator var : field.getVariables()) {
-                    String fieldName = var.getNameAsString();
-                    String fieldType = var.getTypeAsString();
-
-                    // Check for @Column annotation
-                    for (AnnotationExpr ann : field.getAnnotations()) {
-                        if ("Column".equals(ann.getNameAsString())) {
-                            String colName = extractAnnotationStringAttr(ann, "name");
-                            if (colName == null) colName = fieldName;
-                            columns.add(Map.of("name", colName, "field", fieldName, "type", fieldType));
-                        } else if ("Id".equals(ann.getNameAsString())) {
-                            columns.add(Map.of("name", fieldName, "field", fieldName, "type", fieldType));
-                        }
-                    }
-                }
-            }
+            String tableName = extractTableName(classDecl, className);
+            List<Map<String, String>> columns = extractColumns(classDecl);
 
             String entityId = ctx.filePath() + ":" + className;
             Map<String, Object> properties = new LinkedHashMap<>();
@@ -148,59 +120,92 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
             nodes.add(node);
             DetectorDbHelper.addDbEdge(entityId, ctx.registry(), nodes, edges);
 
-            // Extract relationship edges from fields
-            for (FieldDeclaration field : classDecl.getFields()) {
-                for (AnnotationExpr ann : field.getAnnotations()) {
-                    String annName = ann.getNameAsString();
-                    if (!RELATIONSHIP_ANNOTATIONS.contains(annName)) continue;
+            extractRelationshipEdges(classDecl, entityId, edges);
+        });
 
-                    String relType = RELATIONSHIP_TYPES.get(annName);
+        return DetectorResult.of(nodes, edges);
+    }
 
-                    // Resolve target entity
-                    String targetEntity = extractAnnotationStringAttr(ann, "targetEntity");
-                    if (targetEntity != null && targetEntity.endsWith(".class")) {
-                        targetEntity = targetEntity.replace(".class", "");
-                    }
+    private String extractTableName(ClassOrInterfaceDeclaration classDecl, String className) {
+        for (AnnotationExpr ann : classDecl.getAnnotations()) {
+            if (!"Table".equals(ann.getNameAsString())) continue;
+            String name = extractAnnotationStringAttr(ann, PROP_NAME);
+            if (name == null) name = extractAnnotationValue(ann);
+            if (name != null) return name;
+        }
+        return className.toLowerCase();
+    }
 
-                    if (targetEntity == null) {
-                        // Try to resolve from field type / generic type argument
-                        for (VariableDeclarator var : field.getVariables()) {
-                            Type type = var.getType();
-                            if (type.isClassOrInterfaceType()) {
-                                ClassOrInterfaceType cit = type.asClassOrInterfaceType();
-                                if (cit.getTypeArguments().isPresent()) {
-                                    // Generic type like List<Order> -> Order
-                                    var typeArgs = cit.getTypeArguments().get();
-                                    if (!typeArgs.isEmpty()) {
-                                        targetEntity = typeArgs.get(0).asString();
-                                    }
-                                } else {
-                                    targetEntity = cit.getNameAsString();
-                                }
-                                break;
-                            }
-                        }
-                    }
+    private List<Map<String, String>> extractColumns(ClassOrInterfaceDeclaration classDecl) {
+        List<Map<String, String>> columns = new ArrayList<>();
+        for (FieldDeclaration field : classDecl.getFields()) {
+            for (VariableDeclarator var : field.getVariables()) {
+                addColumnFromAnnotations(field, var.getNameAsString(), var.getTypeAsString(), columns);
+            }
+        }
+        return columns;
+    }
 
-                    if (targetEntity != null) {
-                        String mappedBy = extractAnnotationStringAttr(ann, "mappedBy");
-                        Map<String, Object> edgeProps = new LinkedHashMap<>();
-                        edgeProps.put("relationship_type", relType);
-                        if (mappedBy != null) edgeProps.put("mapped_by", mappedBy);
-
-                        CodeEdge edge = new CodeEdge();
-                        edge.setId(entityId + "->maps_to->*:" + targetEntity);
-                        edge.setKind(EdgeKind.MAPS_TO);
-                        edge.setSourceId(entityId);
-                        edge.setTarget(new CodeNode("*:" + targetEntity, NodeKind.ENTITY, targetEntity));
-                        edge.setProperties(edgeProps);
-                        edges.add(edge);
-                    }
-                }
+    private void addColumnFromAnnotations(FieldDeclaration field, String fieldName,
+                                           String fieldType, List<Map<String, String>> columns) {
+        for (AnnotationExpr ann : field.getAnnotations()) {
+            if ("Column".equals(ann.getNameAsString())) {
+                String colName = extractAnnotationStringAttr(ann, PROP_NAME);
+                if (colName == null) colName = fieldName;
+                columns.add(Map.of(PROP_NAME, colName, PROP_FIELD, fieldName, PROP_TYPE, fieldType));
+            } else if ("Id".equals(ann.getNameAsString())) {
+                columns.add(Map.of(PROP_NAME, fieldName, PROP_FIELD, fieldName, PROP_TYPE, fieldType));
             }
-        });
+        }
+    }
 
-        return DetectorResult.of(nodes, edges);
+    private void extractRelationshipEdges(ClassOrInterfaceDeclaration classDecl,
+                                            String entityId, List<CodeEdge> edges) {
+        for (FieldDeclaration field : classDecl.getFields()) {
+            for (AnnotationExpr ann : field.getAnnotations()) {
+                String annName = ann.getNameAsString();
+                if (!RELATIONSHIP_ANNOTATIONS.contains(annName)) continue;
+
+                String relType = RELATIONSHIP_TYPES.get(annName);
+                String targetEntity = resolveTargetEntity(ann, field);
+                if (targetEntity == null) continue;
+
+                String mappedBy = extractAnnotationStringAttr(ann, "mappedBy");
+                Map<String, Object> edgeProps = new LinkedHashMap<>();
+                edgeProps.put("relationship_type", relType);
+                if (mappedBy != null) edgeProps.put("mapped_by", mappedBy);
+
+                CodeEdge edge = new CodeEdge();
+                edge.setId(entityId + "->maps_to->*:" + targetEntity);
+                edge.setKind(EdgeKind.MAPS_TO);
+                edge.setSourceId(entityId);
+                edge.setTarget(new CodeNode("*:" + targetEntity, NodeKind.ENTITY, targetEntity));
+                edge.setProperties(edgeProps);
+                edges.add(edge);
+            }
+        }
+    }
+
+    private String resolveTargetEntity(AnnotationExpr ann, FieldDeclaration field) {
+        String targetEntity = extractAnnotationStringAttr(ann, "targetEntity");
+        if (targetEntity != null && targetEntity.endsWith(".class")) {
+            targetEntity = targetEntity.replace(".class", "");
+        }
+        if (targetEntity != null) return targetEntity;
+
+        for (VariableDeclarator var : field.getVariables()) {
+            Type type = var.getType();
+            if (!type.isClassOrInterfaceType()) continue;
+            ClassOrInterfaceType cit = type.asClassOrInterfaceType();
+            if (cit.getTypeArguments().isPresent()) {
+                var typeArgs = cit.getTypeArguments().get();
+                if (!typeArgs.isEmpty()) return typeArgs.get(0).asString();
+            } else {
+                return cit.getNameAsString();
+            }
+            break;
+        }
+        return null;
     }
 
     private String extractAnnotationStringAttr(AnnotationExpr ann, String attrName) {
@@ -256,7 +261,7 @@ private DetectorResult detectWithRegex(DetectorContext ctx) {
                     Matcher fm = FIELD_RE.matcher(lines[k]);
                     if (fm.find()) {
                         String colName = colNameMatch.find() ? colNameMatch.group(1) : fm.group(2);
-                        columns.add(Map.of("name", colName, "field", fm.group(2), "type", fm.group(1).trim()));
+                        columns.add(Map.of(PROP_NAME, colName, PROP_FIELD, fm.group(2), PROP_TYPE, fm.group(1).trim()));
                         break;
                     }
                 }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/KafkaDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/KafkaDetector.java
index 737dd416..69866a2c 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/KafkaDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/KafkaDetector.java
@@ -28,6 +28,8 @@
 )
 @Component
 public class KafkaDetector extends AbstractRegexDetector {
+    private static final String PROP_TOPIC = "topic";
+
 
     private static final Pattern CLASS_RE = Pattern.compile(
             "(?:(?:public|internal|private|protected|data|abstract|open|sealed|enum|inline|value)\\s+)*" +
@@ -87,7 +89,7 @@ public DetectorResult detect(DetectorContext ctx) {
                         String topic = fallback.group(1);
                         String topicId = ensureTopicNode(topic, seenTopics, nodes, registry);
                         Map<String, Object> props = new LinkedHashMap<>();
-                        props.put("topic", topic);
+                        props.put(PROP_TOPIC, topic);
                         addEdge(classNodeId, topicId, EdgeKind.CONSUMES,
                                 className + " consumes " + topic, props, edges, nodes);
                     }
@@ -97,7 +99,7 @@ public DetectorResult detect(DetectorContext ctx) {
             String topic = m.group(1);
             String topicId = ensureTopicNode(topic, seenTopics, nodes, registry);
             Map<String, Object> props = new LinkedHashMap<>();
-            props.put("topic", topic);
+            props.put(PROP_TOPIC, topic);
             Matcher gm = GROUP_ID_RE.matcher(lines[i]);
             if (gm.find()) props.put("group_id", gm.group(1));
             addEdge(classNodeId, topicId, EdgeKind.CONSUMES,
@@ -112,7 +114,7 @@ public DetectorResult detect(DetectorContext ctx) {
             String topicId = ensureTopicNode(topic, seenTopics, nodes, registry);
             addEdge(classNodeId, topicId, EdgeKind.PRODUCES,
                     className + " produces to " + topic,
-                    Map.of("topic", topic), edges, nodes);
+                    Map.of(PROP_TOPIC, topic), edges, nodes);
         }
 
         return DetectorResult.of(nodes, edges);
@@ -133,7 +135,7 @@ private String ensureTopicNode(String topic, Set<String> seen, List<CodeNode> no
             node.setKind(NodeKind.TOPIC);
             node.setLabel("kafka:" + topic);
             node.getProperties().put("broker", "kafka");
-            node.getProperties().put("topic", topic);
+            node.getProperties().put(PROP_TOPIC, topic);
             nodes.add(node);
         }
         return topicId;
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/MicronautDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/MicronautDetector.java
index 9ac5a959..ae78b423 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/MicronautDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/MicronautDetector.java
@@ -28,6 +28,9 @@
 )
 @Component
 public class MicronautDetector extends AbstractRegexDetector {
+    private static final String PROP_FRAMEWORK = "framework";
+    private static final String PROP_MICRONAUT = "micronaut";
+
 
     private static final Pattern CONTROLLER_RE = Pattern.compile("@Controller\\s*\\(\\s*\"([^\"]*)\"");
     private static final Pattern HTTP_METHOD_RE = Pattern.compile("@(Get|Post|Put|Delete)(?!Mapping)\\s*(?:\\(\\s*\"([^\"]*)\")?\\s*\\)?");
@@ -42,7 +45,7 @@ public class MicronautDetector extends AbstractRegexDetector {
 
     @Override
     public String getName() {
-        return "micronaut";
+        return PROP_MICRONAUT;
     }
 
     @Override
@@ -101,7 +104,7 @@ public DetectorResult detect(DetectorContext ctx) {
             ctrlNode.setFilePath(ctx.filePath());
             ctrlNode.setLineStart(1);
             ctrlNode.getAnnotations().add("@Controller");
-            ctrlNode.getProperties().put("framework", "micronaut");
+            ctrlNode.getProperties().put(PROP_FRAMEWORK, PROP_MICRONAUT);
             ctrlNode.getProperties().put("path", controllerPath);
             nodes.add(ctrlNode);
         }
@@ -137,7 +140,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 node.setFilePath(ctx.filePath());
                 node.setLineStart(lineno);
                 node.getAnnotations().add("@" + hm.group(1));
-                node.getProperties().put("framework", "micronaut");
+                node.getProperties().put(PROP_FRAMEWORK, PROP_MICRONAUT);
                 node.getProperties().put("http_method", httpMethod);
                 node.getProperties().put("path", fullPath);
                 nodes.add(node);
@@ -163,7 +166,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 node.setFilePath(ctx.filePath());
                 node.setLineStart(lineno);
                 node.getAnnotations().add("@" + scope);
-                node.getProperties().put("framework", "micronaut");
+                node.getProperties().put(PROP_FRAMEWORK, PROP_MICRONAUT);
                 node.getProperties().put("bean_scope", scope);
                 nodes.add(node);
             }
@@ -181,7 +184,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 node.setFilePath(ctx.filePath());
                 node.setLineStart(lineno);
                 node.getAnnotations().add("@Client");
-                node.getProperties().put("framework", "micronaut");
+                node.getProperties().put(PROP_FRAMEWORK, PROP_MICRONAUT);
                 node.getProperties().put("client_target", clientTarget);
                 nodes.add(node);
 
@@ -204,7 +207,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 node.setFilePath(ctx.filePath());
                 node.setLineStart(lineno);
                 node.getAnnotations().add("@Inject");
-                node.getProperties().put("framework", "micronaut");
+                node.getProperties().put(PROP_FRAMEWORK, PROP_MICRONAUT);
                 nodes.add(node);
             }
 
@@ -221,7 +224,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 node.setFilePath(ctx.filePath());
                 node.setLineStart(lineno);
                 node.getAnnotations().add("@Scheduled");
-                node.getProperties().put("framework", "micronaut");
+                node.getProperties().put(PROP_FRAMEWORK, PROP_MICRONAUT);
                 node.getProperties().put("fixed_rate", rate);
                 nodes.add(node);
             }
@@ -237,7 +240,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 node.setFilePath(ctx.filePath());
                 node.setLineStart(lineno);
                 node.getAnnotations().add("@EventListener");
-                node.getProperties().put("framework", "micronaut");
+                node.getProperties().put(PROP_FRAMEWORK, PROP_MICRONAUT);
                 nodes.add(node);
             }
         }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/ModuleDepsDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/ModuleDepsDetector.java
index 3f842a78..1d1a9673 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/ModuleDepsDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/ModuleDepsDetector.java
@@ -28,6 +28,10 @@
 )
 @Component
 public class ModuleDepsDetector extends AbstractRegexDetector {
+    private static final String PROP_BUILD_TOOL = "build_tool";
+    private static final String PROP_GRADLE = "gradle";
+    private static final String PROP_UNKNOWN = "unknown";
+
 
     private static final Pattern GRADLE_DEPENDENCY_RE = Pattern.compile(
             "(?:implementation|api|compile|compileOnly|runtimeOnly|testImplementation)\\s+"
@@ -49,7 +53,7 @@ public String getName() {
 
     @Override
     public Set<String> getSupportedLanguages() {
-        return Set.of("java", "xml", "gradle");
+        return Set.of("java", "xml", PROP_GRADLE);
     }
 
     @Override
@@ -78,9 +82,9 @@ private DetectorResult detectMaven(DetectorContext ctx) {
         if (depsIdx > 0) topSection = text.substring(0, depsIdx);
 
         Matcher gm = GROUP_ID_RE.matcher(topSection);
-        String groupId = gm.find() ? gm.group(1) : "unknown";
+        String groupId = gm.find() ? gm.group(1) : PROP_UNKNOWN;
         Matcher am = ARTIFACT_ID_RE.matcher(topSection);
-        String artifactId = am.find() ? am.group(1) : "unknown";
+        String artifactId = am.find() ? am.group(1) : PROP_UNKNOWN;
 
         String moduleId = "module:" + groupId + ":" + artifactId;
         CodeNode moduleNode = new CodeNode();
@@ -92,7 +96,7 @@ private DetectorResult detectMaven(DetectorContext ctx) {
         moduleNode.setLineStart(1);
         moduleNode.getProperties().put("group_id", groupId);
         moduleNode.getProperties().put("artifact_id", artifactId);
-        moduleNode.getProperties().put("build_tool", "maven");
+        moduleNode.getProperties().put(PROP_BUILD_TOOL, "maven");
         nodes.add(moduleNode);
 
         // Sub-modules
@@ -104,7 +108,7 @@ private DetectorResult detectMaven(DetectorContext ctx) {
             subNode.setKind(NodeKind.MODULE);
             subNode.setLabel(subModule);
             subNode.setFqn(groupId + ":" + subModule);
-            subNode.getProperties().put("build_tool", "maven");
+            subNode.getProperties().put(PROP_BUILD_TOOL, "maven");
             subNode.getProperties().put("parent", artifactId);
             nodes.add(subNode);
 
@@ -122,7 +126,7 @@ private DetectorResult detectMaven(DetectorContext ctx) {
             Matcher dg = GROUP_ID_RE.matcher(block);
             Matcher da = ARTIFACT_ID_RE.matcher(block);
             if (da.find()) {
-                String depGroup = dg.find() ? dg.group(1) : "unknown";
+                String depGroup = dg.find() ? dg.group(1) : PROP_UNKNOWN;
                 String depArtifact = da.group(1);
                 String depId = "module:" + depGroup + ":" + depArtifact;
                 CodeEdge edge = new CodeEdge();
@@ -167,7 +171,7 @@ private DetectorResult detectGradle(DetectorContext ctx) {
         moduleNode.setFqn(moduleName);
         moduleNode.setFilePath(ctx.filePath());
         moduleNode.setLineStart(1);
-        moduleNode.getProperties().put("build_tool", "gradle");
+        moduleNode.getProperties().put(PROP_BUILD_TOOL, PROP_GRADLE);
         nodes.add(moduleNode);
 
         for (int i = 0; i < lines.length; i++) {
@@ -217,7 +221,7 @@ private DetectorResult detectGradleSettings(DetectorContext ctx) {
             node.setLabel(modulePath);
             node.setFqn(modulePath);
             node.setFilePath(ctx.filePath());
-            node.getProperties().put("build_tool", "gradle");
+            node.getProperties().put(PROP_BUILD_TOOL, PROP_GRADLE);
             nodes.add(node);
         }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/QuarkusDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/QuarkusDetector.java
index 5da73741..9a14109e 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/QuarkusDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/QuarkusDetector.java
@@ -25,6 +25,9 @@
 )
 @Component
 public class QuarkusDetector extends AbstractRegexDetector {
+    private static final String PROP_FRAMEWORK = "framework";
+    private static final String PROP_QUARKUS = "quarkus";
+
 
     private static final Pattern QUARKUS_TEST_RE = Pattern.compile("@QuarkusTest\\b");
     private static final Pattern CONFIG_PROPERTY_RE = Pattern.compile("@ConfigProperty\\s*\\(\\s*name\\s*=\\s*\"([^\"]+)\"");
@@ -36,7 +39,7 @@ public class QuarkusDetector extends AbstractRegexDetector {
 
     @Override
     public String getName() {
-        return "quarkus";
+        return PROP_QUARKUS;
     }
 
     @Override
@@ -83,7 +86,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 nodes.add(makeNode("quarkus:" + ctx.filePath() + ":quarkus_test:" + lineno,
                         NodeKind.CLASS, "@QuarkusTest " + (className != null ? className : "unknown"),
                         className, lineno, ctx, List.of("@QuarkusTest"),
-                        Map.of("framework", "quarkus", "test", true)));
+                        Map.of(PROP_FRAMEWORK, PROP_QUARKUS, "test", true)));
             }
 
             Matcher cpm = CONFIG_PROPERTY_RE.matcher(lines[i]);
@@ -92,7 +95,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 nodes.add(makeNode("quarkus:" + ctx.filePath() + ":config_property:" + lineno,
                         NodeKind.CONFIG_KEY, "@ConfigProperty(" + configKey + ")",
                         configKey, lineno, ctx, List.of("@ConfigProperty"),
-                        Map.of("framework", "quarkus", "config_key", configKey)));
+                        Map.of(PROP_FRAMEWORK, PROP_QUARKUS, "config_key", configKey)));
             }
 
             Matcher cdim = CDI_SCOPE_RE.matcher(lines[i]);
@@ -102,7 +105,7 @@ public DetectorResult detect(DetectorContext ctx) {
                         NodeKind.MIDDLEWARE, "@" + annotation + " (CDI)",
                         className != null ? className + "." + annotation : annotation, lineno, ctx,
                         List.of("@" + annotation),
-                        Map.of("framework", "quarkus", "cdi_scope", annotation)));
+                        Map.of(PROP_FRAMEWORK, PROP_QUARKUS, "cdi_scope", annotation)));
             }
 
             Matcher sm = SCHEDULED_RE.matcher(lines[i]);
@@ -112,7 +115,7 @@ public DetectorResult detect(DetectorContext ctx) {
                         NodeKind.EVENT, "@Scheduled(" + scheduleExpr + ")",
                         className != null ? className + ".scheduled" : "scheduled", lineno, ctx,
                         List.of("@Scheduled"),
-                        Map.of("framework", "quarkus", "schedule", scheduleExpr)));
+                        Map.of(PROP_FRAMEWORK, PROP_QUARKUS, "schedule", scheduleExpr)));
             }
 
             if (TRANSACTIONAL_RE.matcher(lines[i]).find()) {
@@ -120,14 +123,14 @@ public DetectorResult detect(DetectorContext ctx) {
                         NodeKind.MIDDLEWARE, "@Transactional",
                         className != null ? className + ".transactional" : "transactional", lineno, ctx,
                         List.of("@Transactional"),
-                        Map.of("framework", "quarkus")));
+                        Map.of(PROP_FRAMEWORK, PROP_QUARKUS)));
             }
 
             if (STARTUP_RE.matcher(lines[i]).find()) {
                 nodes.add(makeNode("quarkus:" + ctx.filePath() + ":startup:" + lineno,
                         NodeKind.MIDDLEWARE, "@Startup " + (className != null ? className : "unknown"),
                         className, lineno, ctx, List.of("@Startup"),
-                        Map.of("framework", "quarkus")));
+                        Map.of(PROP_FRAMEWORK, PROP_QUARKUS)));
             }
         }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/RabbitmqDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/RabbitmqDetector.java
index a32cc676..688cafd3 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/RabbitmqDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/RabbitmqDetector.java
@@ -27,6 +27,10 @@
 )
 @Component
 public class RabbitmqDetector extends AbstractJavaMessagingDetector {
+    private static final String PROP_BROKER = "broker";
+    private static final String PROP_EXCHANGE = "exchange";
+    private static final String PROP_RABBITMQ = "rabbitmq";
+
 
     private static final Pattern RABBIT_LISTENER_RE = Pattern.compile(
             "@RabbitListener\\s*\\(\\s*(?:.*?queues?\\s*=\\s*)?[\\{\"]?\\s*\"([^\"]+)\"");
@@ -38,7 +42,7 @@ public class RabbitmqDetector extends AbstractJavaMessagingDetector {
 
     @Override
     public String getName() {
-        return "rabbitmq";
+        return PROP_RABBITMQ;
     }
 
     @Override
@@ -82,7 +86,7 @@ public DetectorResult detect(DetectorContext ctx) {
             if (!m.find()) continue;
             String exchangeOrQueue = m.group(1);
             Map<String, Object> props = new LinkedHashMap<>();
-            props.put("exchange", exchangeOrQueue);
+            props.put(PROP_EXCHANGE, exchangeOrQueue);
             Matcher rk = ROUTING_KEY_RE.matcher(lines[i]);
             if (rk.find()) props.put("routing_key", rk.group(1));
 
@@ -93,8 +97,8 @@ public DetectorResult detect(DetectorContext ctx) {
                 node.setId(queueId);
                 node.setKind(NodeKind.QUEUE);
                 node.setLabel("rabbitmq:" + exchangeOrQueue);
-                node.getProperties().put("broker", "rabbitmq");
-                node.getProperties().put("exchange", exchangeOrQueue);
+                node.getProperties().put(PROP_BROKER, PROP_RABBITMQ);
+                node.getProperties().put(PROP_EXCHANGE, exchangeOrQueue);
                 nodes.add(node);
             }
 
@@ -114,8 +118,8 @@ public DetectorResult detect(DetectorContext ctx) {
                 node.setLabel("rabbitmq:exchange:" + exchangeName);
                 node.setFilePath(ctx.filePath());
                 node.setLineStart(lineNum);
-                node.getProperties().put("broker", "rabbitmq");
-                node.getProperties().put("exchange", exchangeName);
+                node.getProperties().put(PROP_BROKER, PROP_RABBITMQ);
+                node.getProperties().put(PROP_EXCHANGE, exchangeName);
                 nodes.add(node);
             }
         }
@@ -131,7 +135,7 @@ private String ensureQueueNode(String queue, Set<String> seen, List<CodeNode> no
             node.setId(queueId);
             node.setKind(NodeKind.QUEUE);
             node.setLabel("rabbitmq:" + queue);
-            node.getProperties().put("broker", "rabbitmq");
+            node.getProperties().put(PROP_BROKER, PROP_RABBITMQ);
             node.getProperties().put("queue", queue);
             nodes.add(node);
         }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/SpringRestDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/SpringRestDetector.java
index 6c858273..824ee90a 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/SpringRestDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/SpringRestDetector.java
@@ -34,6 +34,11 @@
 )
 @Component
 public class SpringRestDetector extends AbstractJavaParserDetector {
+    private static final String PROP_REQUESTMAPPING = "RequestMapping";
+    private static final String PROP_CONSUMES = "consumes";
+    private static final String PROP_PATH = "path";
+    private static final String PROP_PRODUCES = "produces";
+
 
     // ---- Regex fallback patterns ----
     private static final Pattern MAPPING_RE = Pattern.compile(
@@ -134,8 +139,8 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
                     if (httpMethod == null) continue;
 
                     String path = extractAnnotationPath(ann);
-                    String produces = extractAnnotationAttr(ann, "produces");
-                    String consumes = extractAnnotationAttr(ann, "consumes");
+                    String produces = extractAnnotationAttr(ann, PROP_PRODUCES);
+                    String consumes = extractAnnotationAttr(ann, PROP_CONSUMES);
 
                     String fullPath;
                     if (path != null && !path.isEmpty()) {
@@ -163,10 +168,10 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
                     node.getAnnotations().add("@" + annName);
                     node.getProperties().put("framework", "spring_boot");
                     node.getProperties().put("http_method", httpMethod);
-                    node.getProperties().put("path", fullPath);
+                    node.getProperties().put(PROP_PATH, fullPath);
                     node.getProperties().put("method", methodName);
-                    if (produces != null) node.getProperties().put("produces", produces);
-                    if (consumes != null) node.getProperties().put("consumes", consumes);
+                    if (produces != null) node.getProperties().put(PROP_PRODUCES, produces);
+                    if (consumes != null) node.getProperties().put(PROP_CONSUMES, consumes);
 
                     // Extract parameter annotations
                     List<Map<String, String>> params = new ArrayList<>();
@@ -373,9 +378,9 @@ private DetectorResult detectWithRegex(DetectorContext ctx) {
             node.getAnnotations().add("@" + annotationName);
             node.getProperties().put("framework", "spring_boot");
             node.getProperties().put("http_method", httpMethod);
-            node.getProperties().put("path", fullPath);
-            if (produces != null) node.getProperties().put("produces", produces);
-            if (consumes != null) node.getProperties().put("consumes", consumes);
+            node.getProperties().put(PROP_PATH, fullPath);
+            if (produces != null) node.getProperties().put(PROP_PRODUCES, produces);
+            if (consumes != null) node.getProperties().put(PROP_CONSUMES, consumes);
             nodes.add(node);
 
             CodeEdge edge = new CodeEdge();
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/SpringSecurityDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/SpringSecurityDetector.java
index efecfeb7..342290dc 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/SpringSecurityDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/SpringSecurityDetector.java
@@ -30,6 +30,11 @@
 )
 @Component
 public class SpringSecurityDetector extends AbstractJavaParserDetector {
+    private static final String PROP_AUTH_REQUIRED = "auth_required";
+    private static final String PROP_AUTH_TYPE = "auth_type";
+    private static final String PROP_ROLES = "roles";
+    private static final String PROP_SPRING_SECURITY = "spring_security";
+
 
     // ---- Regex fallback patterns ----
     private static final Pattern SECURED_RE = Pattern.compile(
@@ -51,7 +56,7 @@ public class SpringSecurityDetector extends AbstractJavaParserDetector {
 
     @Override
     public String getName() {
-        return "spring_security";
+        return PROP_SPRING_SECURITY;
     }
 
     @Override
@@ -85,11 +90,11 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
                 if ("EnableWebSecurity".equals(annName)) {
                     nodes.add(guardNode("auth:" + ctx.filePath() + ":EnableWebSecurity:" + line,
                             "@EnableWebSecurity", line, ctx, List.of("@EnableWebSecurity"),
-                            Map.of("auth_type", "spring_security", "roles", List.of(), "auth_required", true)));
+                            Map.of(PROP_AUTH_TYPE, PROP_SPRING_SECURITY, PROP_ROLES, List.of(), PROP_AUTH_REQUIRED, true)));
                 } else if ("EnableMethodSecurity".equals(annName)) {
                     nodes.add(guardNode("auth:" + ctx.filePath() + ":EnableMethodSecurity:" + line,
                             "@EnableMethodSecurity", line, ctx, List.of("@EnableMethodSecurity"),
-                            Map.of("auth_type", "spring_security", "roles", List.of(), "auth_required", true)));
+                            Map.of(PROP_AUTH_TYPE, PROP_SPRING_SECURITY, PROP_ROLES, List.of(), PROP_AUTH_REQUIRED, true)));
                 }
             }
 
@@ -102,7 +107,7 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
                     String methodName = method.getNameAsString();
                     nodes.add(guardNode("auth:" + ctx.filePath() + ":SecurityFilterChain:" + methodLine,
                             "SecurityFilterChain:" + methodName, methodLine, ctx, List.of(),
-                            Map.of("auth_type", "spring_security", "roles", List.of(), "method_name", methodName, "auth_required", true)));
+                            Map.of(PROP_AUTH_TYPE, PROP_SPRING_SECURITY, PROP_ROLES, List.of(), "method_name", methodName, PROP_AUTH_REQUIRED, true)));
                 }
 
                 for (AnnotationExpr ann : method.getAnnotations()) {
@@ -113,22 +118,22 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
                         List<String> roles = extractRolesFromAstAnnotation(ann);
                         nodes.add(guardNode("auth:" + ctx.filePath() + ":Secured:" + line,
                                 "@Secured", line, ctx, List.of("@Secured"),
-                                Map.of("auth_type", "spring_security", "roles", roles, "auth_required", true)));
+                                Map.of(PROP_AUTH_TYPE, PROP_SPRING_SECURITY, PROP_ROLES, roles, PROP_AUTH_REQUIRED, true)));
                     } else if ("PreAuthorize".equals(annName)) {
                         String expr = extractAnnotationStringValue(ann);
                         List<String> roles = expr != null ? extractRolesFromSpel(expr) : List.of();
                         Map<String, Object> props = new LinkedHashMap<>();
-                        props.put("auth_type", "spring_security");
-                        props.put("roles", roles);
+                        props.put(PROP_AUTH_TYPE, PROP_SPRING_SECURITY);
+                        props.put(PROP_ROLES, roles);
                         if (expr != null) props.put("expression", expr);
-                        props.put("auth_required", true);
+                        props.put(PROP_AUTH_REQUIRED, true);
                         nodes.add(guardNode("auth:" + ctx.filePath() + ":PreAuthorize:" + line,
                                 "@PreAuthorize", line, ctx, List.of("@PreAuthorize"), props));
                     } else if ("RolesAllowed".equals(annName)) {
                         List<String> roles = extractRolesFromAstAnnotation(ann);
                         nodes.add(guardNode("auth:" + ctx.filePath() + ":RolesAllowed:" + line,
                                 "@RolesAllowed", line, ctx, List.of("@RolesAllowed"),
-                                Map.of("auth_type", "spring_security", "roles", roles, "auth_required", true)));
+                                Map.of(PROP_AUTH_TYPE, PROP_SPRING_SECURITY, PROP_ROLES, roles, PROP_AUTH_REQUIRED, true)));
                     }
                 }
             }
@@ -140,7 +145,7 @@ private DetectorResult detectWithAst(CompilationUnit cu, DetectorContext ctx) {
             int line = findLineNumber(text, m.start());
             nodes.add(guardNode("auth:" + ctx.filePath() + ":authorizeHttpRequests:" + line,
                     ".authorizeHttpRequests()", line, ctx, List.of(),
-                    Map.of("auth_type", "spring_security", "roles", List.of(), "auth_required", true)));
+                    Map.of(PROP_AUTH_TYPE, PROP_SPRING_SECURITY, PROP_ROLES, List.of(), PROP_AUTH_REQUIRED, true)));
         }
 
         return DetectorResult.of(nodes, List.of());
@@ -199,7 +204,7 @@ private DetectorResult detectWithRegex(DetectorContext ctx) {
             List<String> roles = extractRolesFromAnnotation(m.group(1), m.group(2));
             nodes.add(guardNode("auth:" + ctx.filePath() + ":Secured:" + line,
                     "@Secured", line, ctx, List.of("@Secured"),
-                    Map.of("auth_type", "spring_security", "roles", roles, "auth_required", true)));
+                    Map.of(PROP_AUTH_TYPE, PROP_SPRING_SECURITY, PROP_ROLES, roles, PROP_AUTH_REQUIRED, true)));
         }
 
         for (Matcher m = PRE_AUTHORIZE_RE.matcher(text); m.find(); ) {
@@ -207,10 +212,10 @@ private DetectorResult detectWithRegex(DetectorContext ctx) {
             String expr = m.group(1);
             List<String> roles = extractRolesFromSpel(expr);
             Map<String, Object> props = new LinkedHashMap<>();
-            props.put("auth_type", "spring_security");
-            props.put("roles", roles);
+            props.put(PROP_AUTH_TYPE, PROP_SPRING_SECURITY);
+            props.put(PROP_ROLES, roles);
             props.put("expression", expr);
-            props.put("auth_required", true);
+            props.put(PROP_AUTH_REQUIRED, true);
             nodes.add(guardNode("auth:" + ctx.filePath() + ":PreAuthorize:" + line,
                     "@PreAuthorize", line, ctx, List.of("@PreAuthorize"), props));
         }
@@ -220,21 +225,21 @@ private DetectorResult detectWithRegex(DetectorContext ctx) {
             List<String> roles = extractRolesFromAnnotation(m.group(1), m.group(2));
             nodes.add(guardNode("auth:" + ctx.filePath() + ":RolesAllowed:" + line,
                     "@RolesAllowed", line, ctx, List.of("@RolesAllowed"),
-                    Map.of("auth_type", "spring_security", "roles", roles, "auth_required", true)));
+                    Map.of(PROP_AUTH_TYPE, PROP_SPRING_SECURITY, PROP_ROLES, roles, PROP_AUTH_REQUIRED, true)));
         }
 
         for (Matcher m = ENABLE_WEB_SECURITY_RE.matcher(text); m.find(); ) {
             int line = findLineNumber(text, m.start());
             nodes.add(guardNode("auth:" + ctx.filePath() + ":EnableWebSecurity:" + line,
                     "@EnableWebSecurity", line, ctx, List.of("@EnableWebSecurity"),
-                    Map.of("auth_type", "spring_security", "roles", List.of(), "auth_required", true)));
+                    Map.of(PROP_AUTH_TYPE, PROP_SPRING_SECURITY, PROP_ROLES, List.of(), PROP_AUTH_REQUIRED, true)));
         }
 
         for (Matcher m = ENABLE_METHOD_SECURITY_RE.matcher(text); m.find(); ) {
             int line = findLineNumber(text, m.start());
             nodes.add(guardNode("auth:" + ctx.filePath() + ":EnableMethodSecurity:" + line,
                     "@EnableMethodSecurity", line, ctx, List.of("@EnableMethodSecurity"),
-                    Map.of("auth_type", "spring_security", "roles", List.of(), "auth_required", true)));
+                    Map.of(PROP_AUTH_TYPE, PROP_SPRING_SECURITY, PROP_ROLES, List.of(), PROP_AUTH_REQUIRED, true)));
         }
 
         for (Matcher m = SECURITY_FILTER_CHAIN_RE.matcher(text); m.find(); ) {
@@ -242,14 +247,14 @@ private DetectorResult detectWithRegex(DetectorContext ctx) {
             String methodName = m.group(1);
             nodes.add(guardNode("auth:" + ctx.filePath() + ":SecurityFilterChain:" + line,
                     "SecurityFilterChain:" + methodName, line, ctx, List.of(),
-                    Map.of("auth_type", "spring_security", "roles", List.of(), "method_name", methodName, "auth_required", true)));
+                    Map.of(PROP_AUTH_TYPE, PROP_SPRING_SECURITY, PROP_ROLES, List.of(), "method_name", methodName, PROP_AUTH_REQUIRED, true)));
         }
 
         for (Matcher m = AUTHORIZE_HTTP_REQUESTS_RE.matcher(text); m.find(); ) {
             int line = findLineNumber(text, m.start());
             nodes.add(guardNode("auth:" + ctx.filePath() + ":authorizeHttpRequests:" + line,
                     ".authorizeHttpRequests()", line, ctx, List.of(),
-                    Map.of("auth_type", "spring_security", "roles", List.of(), "auth_required", true)));
+                    Map.of(PROP_AUTH_TYPE, PROP_SPRING_SECURITY, PROP_ROLES, List.of(), PROP_AUTH_REQUIRED, true)));
         }
 
         return DetectorResult.of(nodes, List.of());
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/TibcoEmsDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/TibcoEmsDetector.java
index 475523b6..07512504 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/TibcoEmsDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/TibcoEmsDetector.java
@@ -27,6 +27,11 @@
 )
 @Component
 public class TibcoEmsDetector extends AbstractJavaMessagingDetector {
+    private static final String PROP_BROKER = "broker";
+    private static final String PROP_QUEUE = "queue";
+    private static final String PROP_TIBCO_EMS = "tibco_ems";
+    private static final String PROP_TOPIC = "topic";
+
 
     private static final Pattern TIBJMS_FACTORY_RE = Pattern.compile(
             "\\b(TibjmsConnectionFactory|TibjmsQueueConnectionFactory|TibjmsTopicConnectionFactory)\\b");
@@ -44,7 +49,7 @@ public class TibcoEmsDetector extends AbstractJavaMessagingDetector {
 
     @Override
     public String getName() {
-        return "tibco_ems";
+        return PROP_TIBCO_EMS;
     }
 
     @Override
@@ -94,7 +99,7 @@ public DetectorResult detect(DetectorContext ctx) {
                 node.setId(nodeId);
                 node.setKind(NodeKind.MESSAGE_QUEUE);
                 node.setLabel("ems:" + factoryType);
-                node.getProperties().put("broker", "tibco_ems");
+                node.getProperties().put(PROP_BROKER, PROP_TIBCO_EMS);
                 node.getProperties().put("factory_type", factoryType);
                 if (!serverUrls.isEmpty()) node.getProperties().put("server_url", serverUrls.get(0));
                 nodes.add(node);
@@ -116,18 +121,18 @@ public DetectorResult detect(DetectorContext ctx) {
                 String queueName = m.group(1);
                 String queueId = ensureQueueNode(queueName, seenQueues, nodes);
                 if (isProducer) addMessagingEdge(classNodeId, queueId, EdgeKind.SENDS_TO,
-                        className + " sends to " + queueName, Map.of("queue", queueName), edges);
+                        className + " sends to " + queueName, Map.of(PROP_QUEUE, queueName), edges);
                 if (isConsumer) addMessagingEdge(classNodeId, queueId, EdgeKind.RECEIVES_FROM,
-                        className + " receives from " + queueName, Map.of("queue", queueName), edges);
+                        className + " receives from " + queueName, Map.of(PROP_QUEUE, queueName), edges);
             }
             m = CREATE_TOPIC_RE.matcher(lines[i]);
             if (m.find()) {
                 String topicName = m.group(1);
                 String topicId = ensureTopicNode(topicName, seenTopics, nodes);
                 if (isProducer) addMessagingEdge(classNodeId, topicId, EdgeKind.SENDS_TO,
-                        className + " sends to " + topicName, Map.of("topic", topicName), edges);
+                        className + " sends to " + topicName, Map.of(PROP_TOPIC, topicName), edges);
                 if (isConsumer) addMessagingEdge(classNodeId, topicId, EdgeKind.RECEIVES_FROM,
-                        className + " receives from " + topicName, Map.of("topic", topicName), edges);
+                        className + " receives from " + topicName, Map.of(PROP_TOPIC, topicName), edges);
             }
         }
 
@@ -150,8 +155,8 @@ private String ensureQueueNode(String name, Set<String> seen, List<CodeNode> nod
             node.setId(id);
             node.setKind(NodeKind.QUEUE);
             node.setLabel("ems:queue:" + name);
-            node.getProperties().put("broker", "tibco_ems");
-            node.getProperties().put("queue", name);
+            node.getProperties().put(PROP_BROKER, PROP_TIBCO_EMS);
+            node.getProperties().put(PROP_QUEUE, name);
             nodes.add(node);
         }
         return id;
@@ -165,8 +170,8 @@ private String ensureTopicNode(String name, Set<String> seen, List<CodeNode> nod
             node.setId(id);
             node.setKind(NodeKind.TOPIC);
             node.setLabel("ems:topic:" + name);
-            node.getProperties().put("broker", "tibco_ems");
-            node.getProperties().put("topic", name);
+            node.getProperties().put(PROP_BROKER, PROP_TIBCO_EMS);
+            node.getProperties().put(PROP_TOPIC, name);
             nodes.add(node);
         }
         return id;
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/java/WebSocketDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/java/WebSocketDetector.java
index 4982bd25..562775c2 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/java/WebSocketDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/java/WebSocketDetector.java
@@ -28,6 +28,11 @@
 )
 @Component
 public class WebSocketDetector extends AbstractRegexDetector {
+    private static final String PROP_DESTINATION = "destination";
+    private static final String PROP_PROTOCOL = "protocol";
+    private static final String PROP_TYPE = "type";
+    private static final String PROP_WEBSOCKET = "websocket";
+
 
     private static final Pattern CLASS_RE = Pattern.compile("(?:public\\s+)?class\\s+(\\w+)");
     private static final Pattern SERVER_ENDPOINT_RE = Pattern.compile("@ServerEndpoint\\s*\\(\\s*(?:value\\s*=\\s*)?\"([^\"]+)\"");
@@ -42,7 +47,7 @@ public class WebSocketDetector extends AbstractRegexDetector {
 
     @Override
     public String getName() {
-        return "websocket";
+        return PROP_WEBSOCKET;
     }
 
     @Override
@@ -89,8 +94,8 @@ public DetectorResult detect(DetectorContext ctx) {
             node.setLineStart(lineNum);
             node.getAnnotations().add("@ServerEndpoint");
             node.getProperties().put("path", path);
-            node.getProperties().put("protocol", "websocket");
-            node.getProperties().put("type", "jsr356");
+            node.getProperties().put(PROP_PROTOCOL, PROP_WEBSOCKET);
+            node.getProperties().put(PROP_TYPE, "jsr356");
             nodes.add(node);
 
             CodeEdge edge = new CodeEdge();
@@ -120,9 +125,9 @@ public DetectorResult detect(DetectorContext ctx) {
             node.setFilePath(ctx.filePath());
             node.setLineStart(i + 1);
             node.getAnnotations().add("@MessageMapping");
-            node.getProperties().put("destination", destination);
-            node.getProperties().put("protocol", "websocket");
-            node.getProperties().put("type", "stomp");
+            node.getProperties().put(PROP_DESTINATION, destination);
+            node.getProperties().put(PROP_PROTOCOL, PROP_WEBSOCKET);
+            node.getProperties().put(PROP_TYPE, "stomp");
             nodes.add(node);
 
             CodeEdge edge = new CodeEdge();
@@ -143,8 +148,8 @@ public DetectorResult detect(DetectorContext ctx) {
                     sendNode.setId(sendId);
                     sendNode.setKind(NodeKind.WEBSOCKET_ENDPOINT);
                     sendNode.setLabel("WS TOPIC " + sendDest);
-                    sendNode.getProperties().put("destination", sendDest);
-                    sendNode.getProperties().put("protocol", "websocket");
+                    sendNode.getProperties().put(PROP_DESTINATION, sendDest);
+                    sendNode.getProperties().put(PROP_PROTOCOL, PROP_WEBSOCKET);
                     nodes.add(sendNode);
 
                     CodeEdge sendEdge = new CodeEdge();
@@ -169,8 +174,8 @@ public DetectorResult detect(DetectorContext ctx) {
             node.setFilePath(ctx.filePath());
             node.setLineStart(lineNum);
             node.getProperties().put("path", path);
-            node.getProperties().put("protocol", "stomp");
-            node.getProperties().put("type", "stomp_endpoint");
+            node.getProperties().put(PROP_PROTOCOL, "stomp");
+            node.getProperties().put(PROP_TYPE, "stomp_endpoint");
             nodes.add(node);
         }
 
@@ -182,7 +187,7 @@ public DetectorResult detect(DetectorContext ctx) {
             edge.setKind(EdgeKind.PRODUCES);
             edge.setSourceId(classNodeId);
             edge.setTarget(new CodeNode("ws:topic:" + destination, NodeKind.WEBSOCKET_ENDPOINT, destination));
-            edge.setProperties(Map.of("destination", destination));
+            edge.setProperties(Map.of(PROP_DESTINATION, destination));
             edges.add(edge);
         }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/kotlin/KtorRouteDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/kotlin/KtorRouteDetector.java
index b8fc3214..f26b13d1 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/kotlin/KtorRouteDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/kotlin/KtorRouteDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.kotlin;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeNode;
@@ -29,6 +28,9 @@
 )
 @Component
 public class KtorRouteDetector extends AbstractAntlrDetector {
+    private static final String PROP_FRAMEWORK = "framework";
+    private static final String PROP_KTOR = "ktor";
+
 
     private static final Pattern ENDPOINT_PATTERN = Pattern.compile("\\b(get|post|put|delete|patch)\\(\\s*\"([^\"]+)\"\\s*\\)\\s*\\{");
     private static final Pattern ROUTING_PATTERN = Pattern.compile("\\brouting\\s*\\{");
@@ -99,7 +101,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             CodeNode n = new CodeNode(); n.setId("ktor:" + fp + ":routing:" + line);
             n.setKind(NodeKind.MODULE); n.setLabel("routing"); n.setFqn(fp + "::routing");
             n.setFilePath(fp); n.setLineStart(line);
-            n.getProperties().put("framework", "ktor"); n.getProperties().put("type", "router");
+            n.getProperties().put(PROP_FRAMEWORK, PROP_KTOR); n.getProperties().put("type", "router");
             nodes.add(n);
         }
 
@@ -114,7 +116,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             n.setKind(NodeKind.ENDPOINT); n.setLabel(method + " " + path);
             n.setFqn(fp + "::" + method + ":" + path); n.setFilePath(fp); n.setLineStart(line);
             n.getProperties().put("protocol", "REST"); n.getProperties().put("http_method", method);
-            n.getProperties().put("path_pattern", path); n.getProperties().put("framework", "ktor");
+            n.getProperties().put("path_pattern", path); n.getProperties().put(PROP_FRAMEWORK, PROP_KTOR);
             nodes.add(n);
         }
 
@@ -125,7 +127,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             CodeNode n = new CodeNode(); n.setId("ktor:" + fp + ":install:" + feature + ":" + line);
             n.setKind(NodeKind.MIDDLEWARE); n.setLabel("install:" + feature);
             n.setFqn(fp + "::install:" + feature); n.setFilePath(fp); n.setLineStart(line);
-            n.getProperties().put("framework", "ktor"); n.getProperties().put("feature", feature);
+            n.getProperties().put(PROP_FRAMEWORK, PROP_KTOR); n.getProperties().put("feature", feature);
             nodes.add(n);
         }
 
@@ -136,7 +138,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             CodeNode n = new CodeNode(); n.setId("ktor:" + fp + ":auth:" + authName + ":" + line);
             n.setKind(NodeKind.GUARD); n.setLabel("authenticate:" + authName);
             n.setFqn(fp + "::authenticate:" + authName); n.setFilePath(fp); n.setLineStart(line);
-            n.getProperties().put("framework", "ktor"); n.getProperties().put("auth_name", authName);
+            n.getProperties().put(PROP_FRAMEWORK, PROP_KTOR); n.getProperties().put("auth_name", authName);
             nodes.add(n);
         }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/python/CeleryTaskDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/python/CeleryTaskDetector.java
index e3775ee2..fed53143 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/python/CeleryTaskDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/python/CeleryTaskDetector.java
@@ -60,7 +60,6 @@ protected DetectorResult detectWithAst(ParseTree tree, DetectorContext ctx) {
         List<CodeEdge> edges = new ArrayList<>();
         String filePath = ctx.filePath();
         String moduleName = ctx.moduleName();
-        String text = ctx.content();
 
         // Walk for decorated functions (task definitions)
         ParseTreeWalker.DEFAULT.walk(new Python3ParserBaseListener() {
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/python/DjangoAuthDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/python/DjangoAuthDetector.java
index 5ed00883..816fcee5 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/python/DjangoAuthDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/python/DjangoAuthDetector.java
@@ -29,6 +29,11 @@
 )
 @Component
 public class DjangoAuthDetector extends AbstractPythonAntlrDetector {
+    private static final String PROP_AUTH_REQUIRED = "auth_required";
+    private static final String PROP_AUTH_TYPE = "auth_type";
+    private static final String PROP_DJANGO = "django";
+    private static final String PROP_PERMISSIONS = "permissions";
+
 
     // --- Regex fallback patterns ---
     private static final Pattern LOGIN_REQUIRED_RE = Pattern.compile("@login_required\\b");
@@ -153,9 +158,9 @@ private static CodeNode createLoginRequiredGuard(String filePath, String moduleN
         node.setFilePath(filePath);
         node.setLineStart(line);
         node.setAnnotations(List.of("@login_required"));
-        node.getProperties().put("auth_type", "django");
-        node.getProperties().put("permissions", List.of());
-        node.getProperties().put("auth_required", true);
+        node.getProperties().put(PROP_AUTH_TYPE, PROP_DJANGO);
+        node.getProperties().put(PROP_PERMISSIONS, List.of());
+        node.getProperties().put(PROP_AUTH_REQUIRED, true);
         return node;
     }
 
@@ -168,9 +173,9 @@ private static CodeNode createPermissionRequiredGuard(String filePath, String mo
         node.setFilePath(filePath);
         node.setLineStart(line);
         node.setAnnotations(List.of("@permission_required"));
-        node.getProperties().put("auth_type", "django");
-        node.getProperties().put("permissions", List.of(permission));
-        node.getProperties().put("auth_required", true);
+        node.getProperties().put(PROP_AUTH_TYPE, PROP_DJANGO);
+        node.getProperties().put(PROP_PERMISSIONS, List.of(permission));
+        node.getProperties().put(PROP_AUTH_REQUIRED, true);
         return node;
     }
 
@@ -183,10 +188,10 @@ private static CodeNode createUserPassesTestGuard(String filePath, String module
         node.setFilePath(filePath);
         node.setLineStart(line);
         node.setAnnotations(List.of("@user_passes_test"));
-        node.getProperties().put("auth_type", "django");
-        node.getProperties().put("permissions", List.of());
+        node.getProperties().put(PROP_AUTH_TYPE, PROP_DJANGO);
+        node.getProperties().put(PROP_PERMISSIONS, List.of());
         node.getProperties().put("test_function", testFunc);
-        node.getProperties().put("auth_required", true);
+        node.getProperties().put(PROP_AUTH_REQUIRED, true);
         return node;
     }
 
@@ -199,11 +204,11 @@ private static CodeNode createMixinGuard(String filePath, String moduleName, int
         node.setFilePath(filePath);
         node.setLineStart(line);
         node.setAnnotations(List.of("mixin:" + mixin));
-        node.getProperties().put("auth_type", "django");
-        node.getProperties().put("permissions", List.of());
+        node.getProperties().put(PROP_AUTH_TYPE, PROP_DJANGO);
+        node.getProperties().put(PROP_PERMISSIONS, List.of());
         node.getProperties().put("mixin", mixin);
         node.getProperties().put("class_name", className);
-        node.getProperties().put("auth_required", true);
+        node.getProperties().put(PROP_AUTH_REQUIRED, true);
         return node;
     }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/python/FastAPIAuthDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/python/FastAPIAuthDetector.java
index d51fb3e8..70e62a95 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/python/FastAPIAuthDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/python/FastAPIAuthDetector.java
@@ -28,6 +28,12 @@
 )
 @Component
 public class FastAPIAuthDetector extends AbstractPythonAntlrDetector {
+    private static final String PROP_AUTH_FLOW = "auth_flow";
+    private static final String PROP_AUTH_REQUIRED = "auth_required";
+    private static final String PROP_AUTH_TYPE = "auth_type";
+    private static final String PROP_FASTAPI = "fastapi";
+    private static final String PROP_OAUTH2 = "oauth2";
+
 
     // --- Regex fallback patterns ---
     private static final Pattern DEPENDS_AUTH_RE = Pattern.compile(
@@ -143,10 +149,10 @@ private static CodeNode createDependsGuard(String filePath, String moduleName, i
         node.setFilePath(filePath);
         node.setLineStart(line);
         node.setAnnotations(List.of("Depends(" + depName + ")"));
-        node.getProperties().put("auth_type", "fastapi");
-        node.getProperties().put("auth_flow", "oauth2");
+        node.getProperties().put(PROP_AUTH_TYPE, PROP_FASTAPI);
+        node.getProperties().put(PROP_AUTH_FLOW, PROP_OAUTH2);
         node.getProperties().put("dependency", depName);
-        node.getProperties().put("auth_required", true);
+        node.getProperties().put(PROP_AUTH_REQUIRED, true);
         return node;
     }
 
@@ -159,10 +165,10 @@ private static CodeNode createSecurityGuard(String filePath, String moduleName,
         node.setFilePath(filePath);
         node.setLineStart(line);
         node.setAnnotations(List.of("Security(" + schemeName + ")"));
-        node.getProperties().put("auth_type", "fastapi");
-        node.getProperties().put("auth_flow", "oauth2");
+        node.getProperties().put(PROP_AUTH_TYPE, PROP_FASTAPI);
+        node.getProperties().put(PROP_AUTH_FLOW, PROP_OAUTH2);
         node.getProperties().put("scheme", schemeName);
-        node.getProperties().put("auth_required", true);
+        node.getProperties().put(PROP_AUTH_REQUIRED, true);
         return node;
     }
 
@@ -175,9 +181,9 @@ private static CodeNode createHttpBearerGuard(String filePath, String moduleName
         node.setFilePath(filePath);
         node.setLineStart(line);
         node.setAnnotations(List.of("HTTPBearer"));
-        node.getProperties().put("auth_type", "fastapi");
-        node.getProperties().put("auth_flow", "bearer");
-        node.getProperties().put("auth_required", true);
+        node.getProperties().put(PROP_AUTH_TYPE, PROP_FASTAPI);
+        node.getProperties().put(PROP_AUTH_FLOW, "bearer");
+        node.getProperties().put(PROP_AUTH_REQUIRED, true);
         return node;
     }
 
@@ -190,10 +196,10 @@ private static CodeNode createOAuth2PasswordBearerGuard(String filePath, String
         node.setFilePath(filePath);
         node.setLineStart(line);
         node.setAnnotations(List.of("OAuth2PasswordBearer"));
-        node.getProperties().put("auth_type", "fastapi");
-        node.getProperties().put("auth_flow", "oauth2");
+        node.getProperties().put(PROP_AUTH_TYPE, PROP_FASTAPI);
+        node.getProperties().put(PROP_AUTH_FLOW, PROP_OAUTH2);
         node.getProperties().put("token_url", tokenUrl);
-        node.getProperties().put("auth_required", true);
+        node.getProperties().put(PROP_AUTH_REQUIRED, true);
         return node;
     }
 
@@ -206,9 +212,9 @@ private static CodeNode createHttpBasicGuard(String filePath, String moduleName,
         node.setFilePath(filePath);
         node.setLineStart(line);
         node.setAnnotations(List.of("HTTPBasic"));
-        node.getProperties().put("auth_type", "fastapi");
-        node.getProperties().put("auth_flow", "basic");
-        node.getProperties().put("auth_required", true);
+        node.getProperties().put(PROP_AUTH_TYPE, PROP_FASTAPI);
+        node.getProperties().put(PROP_AUTH_FLOW, "basic");
+        node.getProperties().put(PROP_AUTH_REQUIRED, true);
         return node;
     }
 }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/python/KafkaPythonDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/python/KafkaPythonDetector.java
index 43b9d788..ab809f44 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/python/KafkaPythonDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/python/KafkaPythonDetector.java
@@ -30,6 +30,10 @@
 )
 @Component
 public class KafkaPythonDetector extends AbstractAntlrDetector {
+    private static final String PROP_PRODUCER = "producer";
+    private static final String PROP_ROLE = "role";
+    private static final String PROP_TOPIC = "topic";
+
 
     // --- Regex patterns ---
     private static final Pattern PRODUCER_RE = Pattern.compile(
@@ -117,7 +121,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setModule(moduleName);
                 node.setFilePath(fp);
                 node.setLineStart(lineno);
-                node.getProperties().put("role", "producer");
+                node.getProperties().put(PROP_ROLE, PROP_PRODUCER);
                 nodes.add(node);
             }
         }
@@ -132,7 +136,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setModule(moduleName);
                 node.setFilePath(fp);
                 node.setLineStart(lineno);
-                node.getProperties().put("role", "consumer");
+                node.getProperties().put(PROP_ROLE, "consumer");
                 nodes.add(node);
             }
         }
@@ -142,24 +146,24 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             Matcher sm = SEND_RE.matcher(lines[i]);
             if (sm.find() && lines[i].contains("send")) {
                 String topic = sm.group(1);
-                String topicId = ensureTopic(nodes, seenTopics, fp, moduleName, topic, "producer", lineno);
+                String topicId = ensureTopic(nodes, seenTopics, fp, moduleName, topic, PROP_PRODUCER, lineno);
                 CodeEdge edge = new CodeEdge();
                 edge.setId(fileNodeId + "->produces->" + topicId);
                 edge.setKind(EdgeKind.PRODUCES);
                 edge.setSourceId(fileNodeId);
-                edge.getProperties().put("topic", topic);
+                edge.getProperties().put(PROP_TOPIC, topic);
                 edges.add(edge);
                 continue;
             }
             Matcher pm = PRODUCE_RE.matcher(lines[i]);
             if (pm.find()) {
                 String topic = pm.group(1);
-                String topicId = ensureTopic(nodes, seenTopics, fp, moduleName, topic, "producer", lineno);
+                String topicId = ensureTopic(nodes, seenTopics, fp, moduleName, topic, PROP_PRODUCER, lineno);
                 CodeEdge edge = new CodeEdge();
                 edge.setId(fileNodeId + "->produces->" + topicId);
                 edge.setKind(EdgeKind.PRODUCES);
                 edge.setSourceId(fileNodeId);
-                edge.getProperties().put("topic", topic);
+                edge.getProperties().put(PROP_TOPIC, topic);
                 edges.add(edge);
             }
         }
@@ -174,7 +178,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 edge.setId(fileNodeId + "->consumes->" + topicId);
                 edge.setKind(EdgeKind.CONSUMES);
                 edge.setSourceId(fileNodeId);
-                edge.getProperties().put("topic", topic);
+                edge.getProperties().put(PROP_TOPIC, topic);
                 edges.add(edge);
             }
         }
@@ -209,8 +213,8 @@ private String ensureTopic(List<CodeNode> nodes, Set<String> seenTopics,
             node.setFilePath(fp);
             node.setLineStart(lineno);
             node.getProperties().put("broker", "kafka");
-            node.getProperties().put("topic", topic);
-            node.getProperties().put("role", role);
+            node.getProperties().put(PROP_TOPIC, topic);
+            node.getProperties().put(PROP_ROLE, role);
             nodes.add(node);
         }
         return topicId;
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/python/PythonStructuresDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/python/PythonStructuresDetector.java
index 4a03d135..117dd77c 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/python/PythonStructuresDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/python/PythonStructuresDetector.java
@@ -8,7 +8,6 @@
 import io.github.randomcodespace.iq.model.CodeNode;
 import io.github.randomcodespace.iq.model.EdgeKind;
 import io.github.randomcodespace.iq.model.NodeKind;
-import org.antlr.v4.runtime.ParserRuleContext;
 import org.antlr.v4.runtime.tree.ParseTree;
 import org.antlr.v4.runtime.tree.ParseTreeWalker;
 import org.springframework.stereotype.Component;
@@ -33,6 +32,8 @@
 )
 @Component
 public class PythonStructuresDetector extends AbstractPythonAntlrDetector {
+    private static final String PROP_EXPORTED = "exported";
+
 
     // --- Regex patterns (for fallback) ---
     private static final Pattern CLASS_RE = Pattern.compile(
@@ -114,7 +115,7 @@ public void enterFuncdef(Python3Parser.FuncdefContext funcCtx) {
                     properties.put("async", true);
                 }
                 if (allInfo.exports != null && allInfo.exports.contains(funcName)) {
-                    properties.put("exported", true);
+                    properties.put(PROP_EXPORTED, true);
                 }
 
                 if (indent == 0) {
@@ -148,12 +149,12 @@ public void enterImport_from(Python3Parser.Import_fromContext importCtx) {
                 // from os.path import join
                 StringBuilder fromModule = new StringBuilder();
                 if (importCtx.DOT() != null) {
-                    for (var dot : importCtx.DOT()) {
+                    for (var ignored : importCtx.DOT()) {
                         fromModule.append(".");
                     }
                 }
                 if (importCtx.ELLIPSIS() != null) {
-                    for (var ellipsis : importCtx.ELLIPSIS()) {
+                    for (var ignored : importCtx.ELLIPSIS()) {
                         fromModule.append("...");
                     }
                 }
@@ -228,7 +229,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 properties.put("async", true);
             }
             if (allInfo.exports != null && allInfo.exports.contains(funcName)) {
-                properties.put("exported", true);
+                properties.put(PROP_EXPORTED, true);
             }
 
             if (indentLen == 0) {
@@ -301,7 +302,7 @@ private static Map<String, Object> buildBaseProperties(String basesStr, String c
             properties.put("bases", bases);
         }
         if (allExports != null && allExports.contains(className)) {
-            properties.put("exported", true);
+            properties.put(PROP_EXPORTED, true);
         }
         return properties;
     }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/rust/ActixWebDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/rust/ActixWebDetector.java
index 2193c23d..fb83e591 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/rust/ActixWebDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/rust/ActixWebDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.rust;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeNode;
@@ -27,6 +26,12 @@
 )
 @Component
 public class ActixWebDetector extends AbstractAntlrDetector {
+    private static final String PROP_ACTIX_WEB = "actix_web";
+    private static final String PROP_AXUM = "axum";
+    private static final String PROP_FRAMEWORK = "framework";
+    private static final String PROP_HTTP_METHOD = "http_method";
+    private static final String PROP_PATH = "path";
+
 
     private static final Pattern ACTIX_ATTR_RE = Pattern.compile("#\\[(get|post|put|delete)\\s*\\(\\s*\"([^\"]*)\"\\s*\\)\\s*\\]");
     private static final Pattern HTTP_SERVER_RE = Pattern.compile("HttpServer::new\\s*\\(");
@@ -38,7 +43,7 @@ public class ActixWebDetector extends AbstractAntlrDetector {
     private static final Pattern FN_RE = Pattern.compile("(?:pub\\s+)?(?:async\\s+)?fn\\s+(\\w+)");
 
     @Override
-    public String getName() { return "actix_web"; }
+    public String getName() { return PROP_ACTIX_WEB; }
 
     @Override
     public Set<String> getSupportedLanguages() { return Set.of("rust"); }
@@ -55,7 +60,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
         if (text == null || text.isEmpty()) return DetectorResult.empty();
 
         boolean hasMarker = false;
-        for (String marker : List.of("#[get", "#[post", "#[put", "#[delete", "HttpServer::new", "web::get", "web::post", "web::resource", "Router::new", ".layer(", "actix_web::main", "tokio::main", "actix_web", "axum")) {
+        for (String marker : List.of("#[get", "#[post", "#[put", "#[delete", "HttpServer::new", "web::get", "web::post", "web::resource", "Router::new", ".layer(", "actix_web::main", "tokio::main", PROP_ACTIX_WEB, PROP_AXUM)) {
             if (text.contains(marker)) { hasMarker = true; break; }
         }
         if (!hasMarker) return DetectorResult.empty();
@@ -84,9 +89,9 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setFqn(fnName);
                 node.setFilePath(filePath);
                 node.setLineStart(lineno);
-                node.getProperties().put("framework", "actix_web");
-                node.getProperties().put("http_method", method);
-                node.getProperties().put("path", path);
+                node.getProperties().put(PROP_FRAMEWORK, PROP_ACTIX_WEB);
+                node.getProperties().put(PROP_HTTP_METHOD, method);
+                node.getProperties().put(PROP_PATH, path);
                 nodes.add(node);
             }
 
@@ -99,7 +104,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setFqn("HttpServer");
                 node.setFilePath(filePath);
                 node.setLineStart(lineno);
-                node.getProperties().put("framework", "actix_web");
+                node.getProperties().put(PROP_FRAMEWORK, PROP_ACTIX_WEB);
                 nodes.add(node);
             }
 
@@ -115,9 +120,9 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setFqn(handler);
                 node.setFilePath(filePath);
                 node.setLineStart(lineno);
-                node.getProperties().put("framework", "actix_web");
-                node.getProperties().put("http_method", method);
-                node.getProperties().put("path", path);
+                node.getProperties().put(PROP_FRAMEWORK, PROP_ACTIX_WEB);
+                node.getProperties().put(PROP_HTTP_METHOD, method);
+                node.getProperties().put(PROP_PATH, path);
                 node.getProperties().put("handler", handler);
                 nodes.add(node);
             }
@@ -132,8 +137,8 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setFqn(path);
                 node.setFilePath(filePath);
                 node.setLineStart(lineno);
-                node.getProperties().put("framework", "actix_web");
-                node.getProperties().put("path", path);
+                node.getProperties().put(PROP_FRAMEWORK, PROP_ACTIX_WEB);
+                node.getProperties().put(PROP_PATH, path);
                 nodes.add(node);
             }
 
@@ -149,9 +154,9 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setFqn(handler);
                 node.setFilePath(filePath);
                 node.setLineStart(lineno);
-                node.getProperties().put("framework", "axum");
-                node.getProperties().put("http_method", method);
-                node.getProperties().put("path", path);
+                node.getProperties().put(PROP_FRAMEWORK, PROP_AXUM);
+                node.getProperties().put(PROP_HTTP_METHOD, method);
+                node.getProperties().put(PROP_PATH, path);
                 node.getProperties().put("handler", handler);
                 nodes.add(node);
             }
@@ -166,7 +171,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setFqn(mwName);
                 node.setFilePath(filePath);
                 node.setLineStart(lineno);
-                node.getProperties().put("framework", "axum");
+                node.getProperties().put(PROP_FRAMEWORK, PROP_AXUM);
                 node.getProperties().put("middleware", mwName);
                 nodes.add(node);
             }
@@ -181,7 +186,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setFqn("main");
                 node.setFilePath(filePath);
                 node.setLineStart(lineno);
-                node.getProperties().put("framework", attr.contains("actix") ? "actix_web" : "tokio");
+                node.getProperties().put(PROP_FRAMEWORK, attr.contains("actix") ? PROP_ACTIX_WEB : "tokio");
                 nodes.add(node);
             }
         }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/rust/RustStructuresDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/rust/RustStructuresDetector.java
index 7ff58d6d..a913ecd2 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/rust/RustStructuresDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/rust/RustStructuresDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.rust;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeEdge;
@@ -29,6 +28,8 @@
 )
 @Component
 public class RustStructuresDetector extends AbstractAntlrDetector {
+    private static final String PROP_TYPE = "type";
+
 
     private static final Pattern USE_RE = Pattern.compile("^\\s*use\\s+([\\w:]+)", Pattern.MULTILINE);
     private static final Pattern STRUCT_RE = Pattern.compile("^\\s*(?:pub\\s+)?struct\\s+(\\w+)", Pattern.MULTILINE);
@@ -84,7 +85,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             CodeNode n = new CodeNode(); n.setId(fp + ":" + name);
             n.setKind(NodeKind.CLASS); n.setLabel(name); n.setFqn(name);
             n.setFilePath(fp); n.setLineStart(findLineNumber(text, m.start()));
-            n.getProperties().put("type", "struct"); nodes.add(n);
+            n.getProperties().put(PROP_TYPE, "struct"); nodes.add(n);
         }
 
         m = TRAIT_RE.matcher(text);
@@ -93,7 +94,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             CodeNode n = new CodeNode(); n.setId(fp + ":" + name);
             n.setKind(NodeKind.INTERFACE); n.setLabel(name); n.setFqn(name);
             n.setFilePath(fp); n.setLineStart(findLineNumber(text, m.start()));
-            n.getProperties().put("type", "trait"); nodes.add(n);
+            n.getProperties().put(PROP_TYPE, "trait"); nodes.add(n);
         }
 
         m = ENUM_RE.matcher(text);
@@ -128,7 +129,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             CodeNode n = new CodeNode(); n.setId(fp + ":" + name);
             n.setKind(NodeKind.METHOD); n.setLabel(name); n.setFqn(name);
             n.setFilePath(fp); n.setLineStart(findLineNumber(text, m.start()));
-            n.getProperties().put("type", "function"); nodes.add(n);
+            n.getProperties().put(PROP_TYPE, "function"); nodes.add(n);
         }
 
         m = MACRO_RE.matcher(text);
@@ -137,7 +138,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             CodeNode n = new CodeNode(); n.setId(fp + ":macro:" + name);
             n.setKind(NodeKind.METHOD); n.setLabel(name + "!"); n.setFqn(name + "!");
             n.setFilePath(fp); n.setLineStart(findLineNumber(text, m.start()));
-            n.getProperties().put("type", "macro"); nodes.add(n);
+            n.getProperties().put(PROP_TYPE, "macro"); nodes.add(n);
         }
 
         return DetectorResult.of(nodes, edges);
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/typescript/FastifyRouteDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/typescript/FastifyRouteDetector.java
index a38e9678..2b7bcae0 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/typescript/FastifyRouteDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/typescript/FastifyRouteDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.typescript;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeEdge;
@@ -31,6 +30,9 @@
 )
 @Component
 public class FastifyRouteDetector extends AbstractAntlrDetector {
+    private static final String PROP_FASTIFY = "fastify";
+    private static final String PROP_FRAMEWORK = "framework";
+
 
     /**
      * Guard pattern: file must contain a Fastify import/require to be considered.
@@ -116,7 +118,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.getProperties().put("protocol", "REST");
             node.getProperties().put("http_method", method);
             node.getProperties().put("path_pattern", path);
-            node.getProperties().put("framework", "fastify");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_FASTIFY);
             nodes.add(node);
         }
 
@@ -148,7 +150,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.getProperties().put("protocol", "REST");
             node.getProperties().put("http_method", method);
             node.getProperties().put("path_pattern", path);
-            node.getProperties().put("framework", "fastify");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_FASTIFY);
 
             Matcher schemaMatcher = SCHEMA_PATTERN.matcher(routeBlock);
             if (schemaMatcher.find()) {
@@ -170,7 +172,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             edge.setId(edgeSource + "->" + edgeTarget);
             edge.setKind(EdgeKind.IMPORTS);
             edge.setSourceId(edgeSource);
-            edge.getProperties().put("framework", "fastify");
+            edge.getProperties().put(PROP_FRAMEWORK, PROP_FASTIFY);
             edge.getProperties().put("plugin", pluginRef);
             edges.add(edge);
         }
@@ -190,7 +192,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "fastify");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_FASTIFY);
             node.getProperties().put("hook_name", hookName);
             nodes.add(node);
         }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/typescript/KafkaJSDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/typescript/KafkaJSDetector.java
index f0d8f18c..b7560aaf 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/typescript/KafkaJSDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/typescript/KafkaJSDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.typescript;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeEdge;
@@ -28,6 +27,9 @@
 )
 @Component
 public class KafkaJSDetector extends AbstractAntlrDetector {
+    private static final String PROP_KAFKA = "kafka";
+    private static final String PROP_TOPIC = "topic";
+
 
     private static final Pattern KAFKA_NEW_RE = Pattern.compile("new\\s+Kafka\\s*\\(\\s*\\{");
     private static final Pattern PRODUCER_RE = Pattern.compile("\\.producer\\s*\\(\\s*\\)");
@@ -68,7 +70,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
         String fp = ctx.filePath();
         String moduleName = ctx.moduleName();
 
-        if (!text.contains("Kafka") && !text.contains("kafka")) {
+        if (!text.contains("Kafka") && !text.contains(PROP_KAFKA)) {
             return DetectorResult.empty();
         }
 
@@ -90,7 +92,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setModule(moduleName);
                 node.setFilePath(fp);
                 node.setLineStart(lineno);
-                node.getProperties().put("broker", "kafka");
+                node.getProperties().put("broker", PROP_KAFKA);
                 node.getProperties().put("library", "kafkajs");
                 nodes.add(node);
             }
@@ -117,7 +119,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 edge.setId(fileNodeId + "->produces->" + topicId);
                 edge.setKind(EdgeKind.PRODUCES);
                 edge.setSourceId(fileNodeId);
-                edge.getProperties().put("topic", topic);
+                edge.getProperties().put(PROP_TOPIC, topic);
                 edges.add(edge);
             }
 
@@ -146,7 +148,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 edge.setId(fileNodeId + "->consumes->" + topicId);
                 edge.setKind(EdgeKind.CONSUMES);
                 edge.setSourceId(fileNodeId);
-                edge.getProperties().put("topic", topic);
+                edge.getProperties().put(PROP_TOPIC, topic);
                 edges.add(edge);
             }
 
@@ -185,8 +187,8 @@ private String ensureTopic(List<CodeNode> nodes, Set<String> seenTopics,
             node.setModule(moduleName);
             node.setFilePath(fp);
             node.setLineStart(lineno);
-            node.getProperties().put("broker", "kafka");
-            node.getProperties().put("topic", topic);
+            node.getProperties().put("broker", PROP_KAFKA);
+            node.getProperties().put(PROP_TOPIC, topic);
             nodes.add(node);
         }
         return topicId;
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/typescript/MongooseORMDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/typescript/MongooseORMDetector.java
index 74c0fafe..df1a1feb 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/typescript/MongooseORMDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/typescript/MongooseORMDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.typescript;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeEdge;
@@ -28,6 +27,10 @@
 )
 @Component
 public class MongooseORMDetector extends AbstractAntlrDetector {
+    private static final String PROP_DEFINITION = "definition";
+    private static final String PROP_FRAMEWORK = "framework";
+    private static final String PROP_MONGOOSE = "mongoose";
+
 
     private static final Pattern MODEL_RE = Pattern.compile(
             "mongoose\\.model\\s*\\(\\s*['\"](\\w+)['\"]"
@@ -90,7 +93,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "mongoose");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_MONGOOSE);
             nodes.add(node);
         }
 
@@ -108,8 +111,8 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "mongoose");
-            node.getProperties().put("definition", "schema");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_MONGOOSE);
+            node.getProperties().put(PROP_DEFINITION, "schema");
             nodes.add(node);
         }
 
@@ -128,8 +131,8 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "mongoose");
-            node.getProperties().put("definition", "model");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_MONGOOSE);
+            node.getProperties().put(PROP_DEFINITION, "model");
             nodes.add(node);
         }
 
@@ -145,7 +148,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
         }
         if (!virtuals.isEmpty()) {
             for (CodeNode node : nodes) {
-                if ("schema".equals(node.getProperties().get("definition"))) {
+                if ("schema".equals(node.getProperties().get(PROP_DEFINITION))) {
                     node.getProperties().put("virtuals", virtuals);
                 }
             }
@@ -168,7 +171,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setModule(moduleName);
                 node.setFilePath(filePath);
                 node.setLineStart(line);
-                node.getProperties().put("framework", "mongoose");
+                node.getProperties().put(PROP_FRAMEWORK, PROP_MONGOOSE);
                 node.getProperties().put("hook_type", hookType);
                 node.getProperties().put("event", eventName);
                 nodes.add(node);
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/typescript/NestJSGuardsDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/typescript/NestJSGuardsDetector.java
index 177509c4..6bc34188 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/typescript/NestJSGuardsDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/typescript/NestJSGuardsDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.typescript;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeNode;
@@ -27,6 +26,10 @@
 )
 @Component
 public class NestJSGuardsDetector extends AbstractAntlrDetector {
+    private static final String PROP_AUTH_TYPE = "auth_type";
+    private static final String PROP_NESTJS_GUARD = "nestjs_guard";
+    private static final String PROP_ROLES = "roles";
+
 
     private static final Pattern NESTJS_IMPORT = Pattern.compile("from\\s+['\"]@nestjs/");
 
@@ -92,9 +95,9 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setFilePath(filePath);
                 node.setLineStart(line);
                 node.getAnnotations().add("@UseGuards");
-                node.getProperties().put("auth_type", "nestjs_guard");
+                node.getProperties().put(PROP_AUTH_TYPE, PROP_NESTJS_GUARD);
                 node.getProperties().put("guard_name", guardName);
-                node.getProperties().put("roles", List.of());
+                node.getProperties().put(PROP_ROLES, List.of());
                 nodes.add(node);
             }
         }
@@ -114,8 +117,8 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFilePath(filePath);
             node.setLineStart(line);
             node.getAnnotations().add("@Roles");
-            node.getProperties().put("auth_type", "nestjs_guard");
-            node.getProperties().put("roles", roles);
+            node.getProperties().put(PROP_AUTH_TYPE, PROP_NESTJS_GUARD);
+            node.getProperties().put(PROP_ROLES, roles);
             nodes.add(node);
         }
 
@@ -132,9 +135,9 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("auth_type", "nestjs_guard");
+            node.getProperties().put(PROP_AUTH_TYPE, PROP_NESTJS_GUARD);
             node.getProperties().put("guard_impl", "canActivate");
-            node.getProperties().put("roles", List.of());
+            node.getProperties().put(PROP_ROLES, List.of());
             nodes.add(node);
         }
 
@@ -153,9 +156,9 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFilePath(filePath);
             node.setLineStart(line);
             node.getAnnotations().add("AuthGuard");
-            node.getProperties().put("auth_type", "nestjs_guard");
+            node.getProperties().put(PROP_AUTH_TYPE, PROP_NESTJS_GUARD);
             node.getProperties().put("strategy", strategy);
-            node.getProperties().put("roles", List.of());
+            node.getProperties().put(PROP_ROLES, List.of());
             nodes.add(node);
         }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/typescript/PassportJwtDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/typescript/PassportJwtDetector.java
index 4c13148d..4ce5a372 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/typescript/PassportJwtDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/typescript/PassportJwtDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.typescript;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeNode;
@@ -27,6 +26,9 @@
 )
 @Component
 public class PassportJwtDetector extends AbstractAntlrDetector {
+    private static final String PROP_AUTH_TYPE = "auth_type";
+    private static final String PROP_JWT = "jwt";
+
 
     private static final Pattern PASSPORT_USE_PATTERN = Pattern.compile(
             "passport\\.use\\(\\s*new\\s+(\\w+Strategy)\\s*\\("
@@ -86,7 +88,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("auth_type", "passport");
+            node.getProperties().put(PROP_AUTH_TYPE, "passport");
             node.getProperties().put("strategy", strategyName);
             nodes.add(node);
         }
@@ -105,7 +107,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("auth_type", "jwt");
+            node.getProperties().put(PROP_AUTH_TYPE, PROP_JWT);
             node.getProperties().put("strategy", strategy);
             nodes.add(node);
         }
@@ -123,7 +125,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("auth_type", "jwt");
+            node.getProperties().put(PROP_AUTH_TYPE, PROP_JWT);
             nodes.add(node);
         }
 
@@ -140,7 +142,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("auth_type", "jwt");
+            node.getProperties().put(PROP_AUTH_TYPE, PROP_JWT);
             node.getProperties().put("library", "express-jwt");
             nodes.add(node);
         }
@@ -158,7 +160,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("auth_type", "jwt");
+            node.getProperties().put(PROP_AUTH_TYPE, PROP_JWT);
             node.getProperties().put("library", "express-jwt");
             nodes.add(node);
         }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/typescript/RemixRouteDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/typescript/RemixRouteDetector.java
index 2f018185..e73865cd 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/typescript/RemixRouteDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/typescript/RemixRouteDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.typescript;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeNode;
@@ -27,6 +26,11 @@
 )
 @Component
 public class RemixRouteDetector extends AbstractAntlrDetector {
+    private static final String PROP_FRAMEWORK = "framework";
+    private static final String PROP_REMIX = "remix";
+    private static final String PROP_ROUTE_PATH = "route_path";
+    private static final String PROP_TYPE = "type";
+
 
     private static final Pattern LOADER_PATTERN = Pattern.compile(
             "export\\s+(?:async\\s+)?function\\s+loader\\s*\\("
@@ -90,11 +94,11 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "remix");
-            node.getProperties().put("type", "loader");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_REMIX);
+            node.getProperties().put(PROP_TYPE, "loader");
             node.getProperties().put("http_method", "GET");
             if (routePath != null) {
-                node.getProperties().put("route_path", routePath);
+                node.getProperties().put(PROP_ROUTE_PATH, routePath);
             }
             nodes.add(node);
         }
@@ -112,11 +116,11 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "remix");
-            node.getProperties().put("type", "action");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_REMIX);
+            node.getProperties().put(PROP_TYPE, "action");
             node.getProperties().put("http_method", "POST");
             if (routePath != null) {
-                node.getProperties().put("route_path", routePath);
+                node.getProperties().put(PROP_ROUTE_PATH, routePath);
             }
             nodes.add(node);
         }
@@ -139,10 +143,10 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "remix");
-            node.getProperties().put("type", "component");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_REMIX);
+            node.getProperties().put(PROP_TYPE, "component");
             if (routePath != null) {
-                node.getProperties().put("route_path", routePath);
+                node.getProperties().put(PROP_ROUTE_PATH, routePath);
             }
             if (hasLoaderData) {
                 node.getProperties().put("uses_loader_data", true);
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/typescript/SequelizeORMDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/typescript/SequelizeORMDetector.java
index 652bd919..129e3e80 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/typescript/SequelizeORMDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/typescript/SequelizeORMDetector.java
@@ -1,7 +1,6 @@
 package io.github.randomcodespace.iq.detector.typescript;
 
 import io.github.randomcodespace.iq.detector.AbstractAntlrDetector;
-import io.github.randomcodespace.iq.grammar.AntlrParserFactory;
 import io.github.randomcodespace.iq.detector.DetectorContext;
 import io.github.randomcodespace.iq.detector.DetectorResult;
 import io.github.randomcodespace.iq.model.CodeEdge;
@@ -28,6 +27,9 @@
 )
 @Component
 public class SequelizeORMDetector extends AbstractAntlrDetector {
+    private static final String PROP_FRAMEWORK = "framework";
+    private static final String PROP_SEQUELIZE = "sequelize";
+
 
     private static final Pattern DEFINE_RE = Pattern.compile(
             "sequelize\\.define\\s*\\(\\s*['\"](\\w+)['\"]"
@@ -92,7 +94,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "sequelize");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_SEQUELIZE);
             nodes.add(node);
         }
 
@@ -111,7 +113,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(filePath);
             node.setLineStart(line);
-            node.getProperties().put("framework", "sequelize");
+            node.getProperties().put(PROP_FRAMEWORK, PROP_SEQUELIZE);
             node.getProperties().put("definition", "define");
             nodes.add(node);
         }
@@ -132,7 +134,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
                 node.setModule(moduleName);
                 node.setFilePath(filePath);
                 node.setLineStart(line);
-                node.getProperties().put("framework", "sequelize");
+                node.getProperties().put(PROP_FRAMEWORK, PROP_SEQUELIZE);
                 node.getProperties().put("definition", "class");
                 nodes.add(node);
             }
diff --git a/src/main/java/io/github/randomcodespace/iq/detector/typescript/TypeScriptStructuresDetector.java b/src/main/java/io/github/randomcodespace/iq/detector/typescript/TypeScriptStructuresDetector.java
index 5458fade..6514b6ad 100644
--- a/src/main/java/io/github/randomcodespace/iq/detector/typescript/TypeScriptStructuresDetector.java
+++ b/src/main/java/io/github/randomcodespace/iq/detector/typescript/TypeScriptStructuresDetector.java
@@ -31,6 +31,9 @@
 )
 @Component
 public class TypeScriptStructuresDetector extends AbstractAntlrDetector {
+    private static final String PROP_ASYNC = "async";
+    private static final String PROP_TYPESCRIPT = "typescript";
+
 
     private static final Pattern INTERFACE_RE = Pattern.compile(
             "^\\s*(?:export\\s+)?interface\\s+(\\w+)", Pattern.MULTILINE
@@ -64,7 +67,7 @@ public String getName() {
 
     @Override
     public Set<String> getSupportedLanguages() {
-        return Set.of("typescript", "javascript");
+        return Set.of(PROP_TYPESCRIPT, "javascript");
     }
 
     @Override
@@ -75,7 +78,7 @@ protected ParseTree parse(DetectorContext ctx) {
             return null; // triggers regex fallback
         }
         if ("typescript".equals(ctx.language())) {
-            return AntlrParserFactory.parse("typescript", ctx.content());
+            return AntlrParserFactory.parse(PROP_TYPESCRIPT, ctx.content());
         }
         // JavaScript files use the JS grammar (or fall back to regex if parse fails)
         return AntlrParserFactory.parse("javascript", ctx.content());
@@ -163,7 +166,7 @@ public void enterFunctionDeclaration(TypeScriptParser.FunctionDeclarationContext
                 node.setFilePath(fp);
                 node.setLineStart(lineOf(ruleCtx));
                 if (ruleCtx.Async() != null) {
-                    node.getProperties().put("async", true);
+                    node.getProperties().put(PROP_ASYNC, true);
                 }
                 nodes.add(node);
             }
@@ -324,7 +327,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setFilePath(fp);
             node.setLineStart(findLineNumber(text, m.start()));
             if (isDefault) node.getProperties().put("default", true);
-            if (isAsync) node.getProperties().put("async", true);
+            if (isAsync) node.getProperties().put(PROP_ASYNC, true);
             nodes.add(node);
             existingIds.add(nodeId);
         }
@@ -345,7 +348,7 @@ protected DetectorResult detectWithRegex(DetectorContext ctx) {
             node.setModule(moduleName);
             node.setFilePath(fp);
             node.setLineStart(findLineNumber(text, m.start()));
-            if (isAsync) node.getProperties().put("async", true);
+            if (isAsync) node.getProperties().put(PROP_ASYNC, true);
             nodes.add(node);
             existingIds.add(nodeId);
         }
diff --git a/src/main/java/io/github/randomcodespace/iq/flow/FlowEngine.java b/src/main/java/io/github/randomcodespace/iq/flow/FlowEngine.java
index 6ff1a627..42c0b614 100644
--- a/src/main/java/io/github/randomcodespace/iq/flow/FlowEngine.java
+++ b/src/main/java/io/github/randomcodespace/iq/flow/FlowEngine.java
@@ -16,15 +16,21 @@
  * manually by FlowCommand, FlowController, and BundleCommand.</p>
  */
 public class FlowEngine {
+    private static final String PROP_AUTH = "auth";
+    private static final String PROP_CI = "ci";
+    private static final String PROP_DEPLOY = "deploy";
+    private static final String PROP_OVERVIEW = "overview";
+    private static final String PROP_RUNTIME = "runtime";
 
-    public static final List<String> AVAILABLE_VIEWS = List.of("overview", "ci", "deploy", "runtime", "auth");
+
+    public static final List<String> AVAILABLE_VIEWS = List.of(PROP_OVERVIEW, PROP_CI, PROP_DEPLOY, PROP_RUNTIME, PROP_AUTH);
 
     private static final Map<String, Function<FlowDataSource, FlowDiagram>> VIEW_BUILDERS = Map.of(
-            "overview", FlowViews::buildOverview,
-            "ci", FlowViews::buildCiView,
-            "deploy", FlowViews::buildDeployView,
-            "runtime", FlowViews::buildRuntimeView,
-            "auth", FlowViews::buildAuthView
+            PROP_OVERVIEW, FlowViews::buildOverview,
+            PROP_CI, FlowViews::buildCiView,
+            PROP_DEPLOY, FlowViews::buildDeployView,
+            PROP_RUNTIME, FlowViews::buildRuntimeView,
+            PROP_AUTH, FlowViews::buildAuthView
     );
 
     private final FlowDataSource dataSource;
@@ -76,13 +82,13 @@ public String renderInteractive(String projectName) {
     }
 
     public Map<String, Object> getParentContext(String nodeId) {
-        for (var viewName : List.of("ci", "deploy", "runtime", "auth")) {
+        for (var viewName : List.of(PROP_CI, PROP_DEPLOY, PROP_RUNTIME, PROP_AUTH)) {
             var diagram = generate(viewName);
             for (var sg : diagram.subgraphs()) {
                 for (var node : sg.nodes()) {
                     if (node.id().equals(nodeId)) {
                         var result = new LinkedHashMap<String, Object>();
-                        result.put("parent_view", "overview");
+                        result.put("parent_view", PROP_OVERVIEW);
                         result.put("parent_subgraph", sg.id());
                         result.put("current_view", viewName);
                         return result;
diff --git a/src/main/java/io/github/randomcodespace/iq/flow/FlowModels.java b/src/main/java/io/github/randomcodespace/iq/flow/FlowModels.java
index 53aebad9..fb170d70 100644
--- a/src/main/java/io/github/randomcodespace/iq/flow/FlowModels.java
+++ b/src/main/java/io/github/randomcodespace/iq/flow/FlowModels.java
@@ -11,6 +11,8 @@
  * Data models for flow diagrams -- the single source of truth for all renderers.
  */
 public final class FlowModels {
+    private static final String PROP_LABEL = "label";
+
 
     private FlowModels() {
     }
@@ -36,7 +38,7 @@ public FlowNode(String id, String label, String kind, Map<String, Object> proper
         public Map<String, Object> toMap() {
             var m = new LinkedHashMap<String, Object>();
             m.put("id", id);
-            m.put("label", label);
+            m.put(PROP_LABEL, label);
             m.put("kind", kind);
             m.put("style", style);
             m.put("properties", properties);
@@ -65,7 +67,7 @@ public Map<String, Object> toMap() {
             var m = new LinkedHashMap<String, Object>();
             m.put("source", source);
             m.put("target", target);
-            m.put("label", label);
+            m.put(PROP_LABEL, label);
             m.put("style", style);
             return m;
         }
@@ -92,7 +94,7 @@ public FlowSubgraph(String id, String label, List<FlowNode> nodes) {
         public Map<String, Object> toMap() {
             var m = new LinkedHashMap<String, Object>();
             m.put("id", id);
-            m.put("label", label);
+            m.put(PROP_LABEL, label);
             m.put("drill_down_view", drillDownView);
             m.put("parent_view", parentView);
             m.put("nodes", nodes.stream().map(FlowNode::toMap).toList());
diff --git a/src/main/java/io/github/randomcodespace/iq/flow/FlowViews.java b/src/main/java/io/github/randomcodespace/iq/flow/FlowViews.java
index 3e8a91e0..6d0611e3 100644
--- a/src/main/java/io/github/randomcodespace/iq/flow/FlowViews.java
+++ b/src/main/java/io/github/randomcodespace/iq/flow/FlowViews.java
@@ -4,7 +4,6 @@
 import io.github.randomcodespace.iq.flow.FlowModels.FlowEdge;
 import io.github.randomcodespace.iq.flow.FlowModels.FlowNode;
 import io.github.randomcodespace.iq.flow.FlowModels.FlowSubgraph;
-import io.github.randomcodespace.iq.model.CodeEdge;
 import io.github.randomcodespace.iq.model.CodeNode;
 import io.github.randomcodespace.iq.model.EdgeKind;
 import io.github.randomcodespace.iq.model.NodeKind;
@@ -23,6 +22,26 @@
  * Mirrors the Python implementation's 5 views exactly.
  */
 public final class FlowViews {
+    private static final String PROP_LR = "LR";
+    private static final String PROP_APP_ENDPOINTS = "app_endpoints";
+    private static final String PROP_APP_MESSAGING = "app_messaging";
+    private static final String PROP_CI = "ci";
+    private static final String PROP_CI_JOBS = "ci_jobs";
+    private static final String PROP_CI_PIPELINES = "ci_pipelines";
+    private static final String PROP_COMPOSE = "compose";
+    private static final String PROP_COUNT = "count";
+    private static final String PROP_DOCKER = "docker";
+    private static final String PROP_ENDPOINT = "endpoint";
+    private static final String PROP_ENDPOINTS = "endpoints";
+    private static final String PROP_EP_PROTECTED = "ep_protected";
+    private static final String PROP_FRONTEND = "frontend";
+    private static final String PROP_GUARDS = "guards";
+    private static final String PROP_INFRA = "infra";
+    private static final String PROP_JOB_ = "job_";
+    private static final String PROP_K8S = "k8s";
+    private static final String PROP_MIDDLEWARE = "middleware";
+    private static final String PROP_TERRAFORM = "terraform";
+
 
     private static final String GITLAB_PREFIX = "gitlab:";
 
@@ -49,14 +68,14 @@ public static FlowDiagram buildOverview(FlowDataSource store) {
                 .filter(n -> isCiNode(n.getId()))
                 .toList();
         if (!workflows.isEmpty() || !ciJobs.isEmpty()) {
-            ciNodes.add(new FlowNode("ci_pipelines", "Pipelines x" + workflows.size(), "pipeline",
-                    Map.of("count", workflows.size())));
+            ciNodes.add(new FlowNode(PROP_CI_PIPELINES, "Pipelines x" + workflows.size(), "pipeline",
+                    Map.of(PROP_COUNT, workflows.size())));
             if (!ciJobs.isEmpty()) {
-                ciNodes.add(new FlowNode("ci_jobs", "Jobs x" + ciJobs.size(), "job",
-                        Map.of("count", ciJobs.size())));
-                edges.add(new FlowEdge("ci_pipelines", "ci_jobs"));
+                ciNodes.add(new FlowNode(PROP_CI_JOBS, "Jobs x" + ciJobs.size(), "job",
+                        Map.of(PROP_COUNT, ciJobs.size())));
+                edges.add(new FlowEdge(PROP_CI_PIPELINES, PROP_CI_JOBS));
             }
-            subgraphs.add(new FlowSubgraph("ci", "CI/CD Pipeline", ciNodes, "ci"));
+            subgraphs.add(new FlowSubgraph(PROP_CI, "CI/CD Pipeline", ciNodes, PROP_CI));
         }
 
         // Infrastructure subgraph
@@ -77,23 +96,23 @@ public static FlowDiagram buildOverview(FlowDataSource store) {
 
             var infraFlowNodes = new ArrayList<FlowNode>();
             if (!k8s.isEmpty()) {
-                infraFlowNodes.add(new FlowNode("infra_k8s", "K8s Resources x" + k8s.size(), "k8s",
-                        Map.of("count", k8s.size())));
+                infraFlowNodes.add(new FlowNode("infra_k8s", "K8s Resources x" + k8s.size(), PROP_K8S,
+                        Map.of(PROP_COUNT, k8s.size())));
             }
             if (!docker.isEmpty()) {
-                infraFlowNodes.add(new FlowNode("infra_docker", "Docker x" + docker.size(), "docker",
-                        Map.of("count", docker.size())));
+                infraFlowNodes.add(new FlowNode("infra_docker", "Docker x" + docker.size(), PROP_DOCKER,
+                        Map.of(PROP_COUNT, docker.size())));
             }
             if (!terraform.isEmpty()) {
-                infraFlowNodes.add(new FlowNode("infra_tf", "Terraform x" + terraform.size(), "terraform",
-                        Map.of("count", terraform.size())));
+                infraFlowNodes.add(new FlowNode("infra_tf", "Terraform x" + terraform.size(), PROP_TERRAFORM,
+                        Map.of(PROP_COUNT, terraform.size())));
             }
             if (!otherInfra.isEmpty()) {
-                infraFlowNodes.add(new FlowNode("infra_other", "Infra x" + otherInfra.size(), "infra",
-                        Map.of("count", otherInfra.size())));
+                infraFlowNodes.add(new FlowNode("infra_other", "Infra x" + otherInfra.size(), PROP_INFRA,
+                        Map.of(PROP_COUNT, otherInfra.size())));
             }
             if (!infraFlowNodes.isEmpty()) {
-                subgraphs.add(new FlowSubgraph("infra", "Infrastructure", infraFlowNodes, "deploy"));
+                subgraphs.add(new FlowSubgraph(PROP_INFRA, "Infrastructure", infraFlowNodes, "deploy"));
             }
         }
 
@@ -111,24 +130,24 @@ public static FlowDiagram buildOverview(FlowDataSource store) {
 
         var appNodes = new ArrayList<FlowNode>();
         if (!endpoints.isEmpty()) {
-            appNodes.add(new FlowNode("app_endpoints", "Endpoints x" + endpoints.size(), "endpoint",
-                    Map.of("count", endpoints.size())));
+            appNodes.add(new FlowNode(PROP_APP_ENDPOINTS, "Endpoints x" + endpoints.size(), PROP_ENDPOINT,
+                    Map.of(PROP_COUNT, endpoints.size())));
         }
         if (!entities.isEmpty()) {
             appNodes.add(new FlowNode("app_entities", "Entities x" + entities.size(), "entity",
-                    Map.of("count", entities.size())));
+                    Map.of(PROP_COUNT, entities.size())));
         }
         if (!components.isEmpty()) {
             appNodes.add(new FlowNode("app_components", "Components x" + components.size(), "component",
-                    Map.of("count", components.size())));
+                    Map.of(PROP_COUNT, components.size())));
         }
         if (!topics.isEmpty()) {
-            appNodes.add(new FlowNode("app_messaging", "Topics/Queues x" + topics.size(), "messaging",
-                    Map.of("count", topics.size())));
+            appNodes.add(new FlowNode(PROP_APP_MESSAGING, "Topics/Queues x" + topics.size(), "messaging",
+                    Map.of(PROP_COUNT, topics.size())));
         }
         if (!dbConns.isEmpty()) {
             appNodes.add(new FlowNode("app_database", "DB Connections x" + dbConns.size(), "database",
-                    Map.of("count", dbConns.size())));
+                    Map.of(PROP_COUNT, dbConns.size())));
         }
         if (appNodes.isEmpty() && (!classes.isEmpty() || !appMethods.isEmpty())) {
             appNodes.add(new FlowNode("app_code",
@@ -138,10 +157,10 @@ public static FlowDiagram buildOverview(FlowDataSource store) {
         if (!appNodes.isEmpty()) {
             subgraphs.add(new FlowSubgraph("app", "Application", appNodes, "runtime"));
             if (!endpoints.isEmpty() && !entities.isEmpty()) {
-                edges.add(new FlowEdge("app_endpoints", "app_entities", "queries"));
+                edges.add(new FlowEdge(PROP_APP_ENDPOINTS, "app_entities", "queries"));
             }
             if (!endpoints.isEmpty() && appNodes.stream().anyMatch(n -> "app_messaging".equals(n.id()))) {
-                edges.add(new FlowEdge("app_endpoints", "app_messaging", null, "dotted"));
+                edges.add(new FlowEdge(PROP_APP_ENDPOINTS, PROP_APP_MESSAGING, null, "dotted"));
             }
         }
 
@@ -152,15 +171,15 @@ public static FlowDiagram buildOverview(FlowDataSource store) {
             var secNodes = new ArrayList<FlowNode>();
             if (!guards.isEmpty()) {
                 secNodes.add(new FlowNode("sec_guards", "Auth Guards x" + guards.size(), "guard",
-                        Map.of("count", guards.size())));
+                        Map.of(PROP_COUNT, guards.size())));
             }
             if (!middleware.isEmpty()) {
-                secNodes.add(new FlowNode("sec_middleware", "Middleware x" + middleware.size(), "middleware",
-                        Map.of("count", middleware.size())));
+                secNodes.add(new FlowNode("sec_middleware", "Middleware x" + middleware.size(), PROP_MIDDLEWARE,
+                        Map.of(PROP_COUNT, middleware.size())));
             }
             subgraphs.add(new FlowSubgraph("security", "Security", secNodes, "auth"));
             if (!guards.isEmpty() && !endpoints.isEmpty()) {
-                edges.add(new FlowEdge("sec_guards", "app_endpoints", "protects", "thick"));
+                edges.add(new FlowEdge("sec_guards", PROP_APP_ENDPOINTS, "protects", "thick"));
             }
         }
 
@@ -169,7 +188,7 @@ public static FlowDiagram buildOverview(FlowDataSource store) {
             var infraSg = subgraphs.stream().filter(sg -> "infra".equals(sg.id())).findFirst();
             if (infraSg.isPresent() && !infraSg.get().nodes().isEmpty()) {
                 String firstInfra = infraSg.get().nodes().getFirst().id();
-                String ciSource = !ciJobs.isEmpty() ? "ci_jobs" : "ci_pipelines";
+                String ciSource = !ciJobs.isEmpty() ? PROP_CI_JOBS : PROP_CI_PIPELINES;
                 edges.add(new FlowEdge(ciSource, firstInfra, "deploys"));
             }
         }
@@ -184,13 +203,13 @@ public static FlowDiagram buildOverview(FlowDataSource store) {
         var stats = new LinkedHashMap<String, Object>();
         stats.put("total_nodes", allNodes.size());
         stats.put("total_edges", countEdges(allNodes));
-        stats.put("endpoints", endpoints.size());
+        stats.put(PROP_ENDPOINTS, endpoints.size());
         stats.put("entities", entities.size());
-        stats.put("guards", guards.size());
+        stats.put(PROP_GUARDS, guards.size());
         stats.put("components", components.size());
         stats.put("infra_resources", infraNodesRaw.size());
 
-        return new FlowDiagram("Architecture Overview", "overview", "LR",
+        return new FlowDiagram("Architecture Overview", "overview", PROP_LR,
                 subgraphs, List.of(), edges, stats);
     }
 
@@ -248,7 +267,7 @@ public static FlowDiagram buildCiView(FlowDataSource store) {
                         props.put(key, j.getProperties().get(key));
                     }
                 }
-                jobNodes.add(new FlowNode("job_" + j.getId().replace(":", "_"), j.getLabel(), "job", props));
+                jobNodes.add(new FlowNode(PROP_JOB_ + j.getId().replace(":", "_"), j.getLabel(), "job", props));
             }
             subgraphs.add(new FlowSubgraph("wf_" + wf.getId().replace(":", "_"), wf.getLabel(), jobNodes));
         }
@@ -259,8 +278,8 @@ public static FlowDiagram buildCiView(FlowDataSource store) {
             for (var edge : node.getEdges()) {
                 if (edge.getKind() == EdgeKind.DEPENDS_ON && isCiNode(edge.getSourceId())) {
                     edges.add(new FlowEdge(
-                            "job_" + edge.getSourceId().replace(":", "_"),
-                            "job_" + edge.getTarget().getId().replace(":", "_"),
+                            PROP_JOB_ + edge.getSourceId().replace(":", "_"),
+                            PROP_JOB_ + edge.getTarget().getId().replace(":", "_"),
                             "needs"));
                 }
             }
@@ -280,7 +299,7 @@ public static FlowDiagram buildCiView(FlowDataSource store) {
         stats.put("jobs", jobs.size());
         stats.put("triggers", triggers.size());
 
-        return new FlowDiagram("CI/CD Pipeline", "ci", "TD",
+        return new FlowDiagram("CI/CD Pipeline", PROP_CI, "TD",
                 subgraphs, List.of(), edges, stats);
     }
 
@@ -311,20 +330,20 @@ public static FlowDiagram buildDeployView(FlowDataSource store) {
         List<CodeNode> other = infra.stream().filter(n -> !grouped.contains(n)).toList();
 
         if (!k8s.isEmpty()) {
-            subgraphs.add(new FlowSubgraph("k8s", "Kubernetes (" + k8s.size() + " resources)",
-                    makeNodes(k8s, "k8s", 20)));
+            subgraphs.add(new FlowSubgraph(PROP_K8S, "Kubernetes (" + k8s.size() + " resources)",
+                    makeNodes(k8s, PROP_K8S, 20)));
         }
         if (!compose.isEmpty()) {
-            subgraphs.add(new FlowSubgraph("compose", "Docker Compose (" + compose.size() + " services)",
-                    makeNodes(compose, "compose", 20)));
+            subgraphs.add(new FlowSubgraph(PROP_COMPOSE, "Docker Compose (" + compose.size() + " services)",
+                    makeNodes(compose, PROP_COMPOSE, 20)));
         }
         if (!tf.isEmpty()) {
-            subgraphs.add(new FlowSubgraph("terraform", "Terraform (" + tf.size() + " resources)",
+            subgraphs.add(new FlowSubgraph(PROP_TERRAFORM, "Terraform (" + tf.size() + " resources)",
                     makeNodes(tf, "tf", 20)));
         }
         if (!docker.isEmpty()) {
-            subgraphs.add(new FlowSubgraph("docker", "Docker (" + docker.size() + " images)",
-                    makeNodes(docker, "docker", 20)));
+            subgraphs.add(new FlowSubgraph(PROP_DOCKER, "Docker (" + docker.size() + " images)",
+                    makeNodes(docker, PROP_DOCKER, 20)));
         }
         if (!other.isEmpty()) {
             subgraphs.add(new FlowSubgraph("other_infra", "Other (" + other.size() + ")",
@@ -350,10 +369,10 @@ public static FlowDiagram buildDeployView(FlowDataSource store) {
         }
 
         var stats = new LinkedHashMap<String, Object>();
-        stats.put("k8s", k8s.size());
-        stats.put("compose", compose.size());
-        stats.put("terraform", tf.size());
-        stats.put("docker", docker.size());
+        stats.put(PROP_K8S, k8s.size());
+        stats.put(PROP_COMPOSE, compose.size());
+        stats.put(PROP_TERRAFORM, tf.size());
+        stats.put(PROP_DOCKER, docker.size());
 
         return new FlowDiagram("Deployment Topology", "deploy", "TD",
                 subgraphs, List.of(), edges, stats);
@@ -386,11 +405,11 @@ public static FlowDiagram buildRuntimeView(FlowDataSource store) {
                     .filter(e -> !"frontend".equals(e.getProperties().get("layer")))
                     .toList();
             if (!feEp.isEmpty()) {
-                frontendNodes.add(new FlowNode("rt_fe_endpoints", "Frontend Routes x" + feEp.size(), "endpoint"));
+                frontendNodes.add(new FlowNode("rt_fe_endpoints", "Frontend Routes x" + feEp.size(), PROP_ENDPOINT));
             }
             if (!beEp.isEmpty()) {
-                backendNodes.add(new FlowNode("rt_be_endpoints", "API Endpoints x" + beEp.size(), "endpoint",
-                        Map.of("count", beEp.size())));
+                backendNodes.add(new FlowNode("rt_be_endpoints", "API Endpoints x" + beEp.size(), PROP_ENDPOINT,
+                        Map.of(PROP_COUNT, beEp.size())));
             }
         }
 
@@ -409,7 +428,7 @@ public static FlowDiagram buildRuntimeView(FlowDataSource store) {
         }
 
         if (!frontendNodes.isEmpty()) {
-            subgraphs.add(new FlowSubgraph("frontend", "Frontend", frontendNodes));
+            subgraphs.add(new FlowSubgraph(PROP_FRONTEND, "Frontend", frontendNodes));
         }
         if (!backendNodes.isEmpty()) {
             subgraphs.add(new FlowSubgraph("backend", "Backend", backendNodes));
@@ -427,13 +446,13 @@ public static FlowDiagram buildRuntimeView(FlowDataSource store) {
         }
 
         var stats = new LinkedHashMap<String, Object>();
-        stats.put("endpoints", endpoints.size());
+        stats.put(PROP_ENDPOINTS, endpoints.size());
         stats.put("entities", entities.size());
         stats.put("components", components.size());
         stats.put("topics", topics.size());
         stats.put("db_connections", dbConns.size());
 
-        return new FlowDiagram("Runtime Architecture", "runtime", "LR",
+        return new FlowDiagram("Runtime Architecture", "runtime", PROP_LR,
                 subgraphs, List.of(), edges, stats);
     }
 
@@ -477,34 +496,34 @@ public static FlowDiagram buildAuthView(FlowDataSource store) {
         for (var entry : guardsByType.entrySet()) {
             guardNodes.add(new FlowNode("auth_" + entry.getKey(),
                     entry.getKey() + " x" + entry.getValue().size(), "guard",
-                    Map.of("auth_type", entry.getKey(), "count", entry.getValue().size())));
+                    Map.of("auth_type", entry.getKey(), PROP_COUNT, entry.getValue().size())));
         }
         if (!middleware.isEmpty()) {
-            guardNodes.add(new FlowNode("auth_middleware", "Middleware x" + middleware.size(), "middleware",
-                    Map.of("count", middleware.size())));
+            guardNodes.add(new FlowNode("auth_middleware", "Middleware x" + middleware.size(), PROP_MIDDLEWARE,
+                    Map.of(PROP_COUNT, middleware.size())));
         }
         if (!guardNodes.isEmpty()) {
-            subgraphs.add(new FlowSubgraph("guards", "Auth Guards", guardNodes));
+            subgraphs.add(new FlowSubgraph(PROP_GUARDS, "Auth Guards", guardNodes));
         }
 
         // Endpoint coverage
         var epNodes = new ArrayList<FlowNode>();
         if (!protectedEndpoints.isEmpty()) {
-            epNodes.add(new FlowNode("ep_protected", "Protected x" + protectedEndpoints.size(), "endpoint",
-                    "success", Map.of("count", protectedEndpoints.size())));
+            epNodes.add(new FlowNode(PROP_EP_PROTECTED, "Protected x" + protectedEndpoints.size(), PROP_ENDPOINT,
+                    "success", Map.of(PROP_COUNT, protectedEndpoints.size())));
         }
         if (!unprotectedEndpoints.isEmpty()) {
-            epNodes.add(new FlowNode("ep_unprotected", "Unprotected x" + unprotectedEndpoints.size(), "endpoint",
-                    "danger", Map.of("count", unprotectedEndpoints.size())));
+            epNodes.add(new FlowNode("ep_unprotected", "Unprotected x" + unprotectedEndpoints.size(), PROP_ENDPOINT,
+                    "danger", Map.of(PROP_COUNT, unprotectedEndpoints.size())));
         }
         if (!epNodes.isEmpty()) {
-            subgraphs.add(new FlowSubgraph("endpoints", "Endpoints", epNodes));
+            subgraphs.add(new FlowSubgraph(PROP_ENDPOINTS, "Endpoints", epNodes));
         }
 
         // Edges: guards -> protected
         for (var gn : guardNodes) {
             if (epNodes.stream().anyMatch(n -> "ep_protected".equals(n.id()))) {
-                edges.add(new FlowEdge(gn.id(), "ep_protected", "protects", "thick"));
+                edges.add(new FlowEdge(gn.id(), PROP_EP_PROTECTED, "protects", "thick"));
             }
         }
 
@@ -512,13 +531,13 @@ public static FlowDiagram buildAuthView(FlowDataSource store) {
                 : (double) protectedEndpoints.size() / endpoints.size() * 100;
 
         var stats = new LinkedHashMap<String, Object>();
-        stats.put("guards", guards.size());
-        stats.put("middleware", middleware.size());
+        stats.put(PROP_GUARDS, guards.size());
+        stats.put(PROP_MIDDLEWARE, middleware.size());
         stats.put("protected", protectedEndpoints.size());
         stats.put("unprotected", unprotectedEndpoints.size());
         stats.put("coverage_pct", Math.round(coverage * 10.0) / 10.0);
 
-        return new FlowDiagram("Auth & Security", "auth", "LR",
+        return new FlowDiagram("Auth & Security", "auth", PROP_LR,
                 subgraphs, List.of(), edges, stats);
     }
 
@@ -547,10 +566,10 @@ private static List<FlowNode> makeNodes(List<CodeNode> nodes, String prefix, int
     private static String[] resolveGroupIndex(CodeNode node, List<CodeNode> k8s, List<CodeNode> compose,
                                                List<CodeNode> tf, List<CodeNode> docker, List<CodeNode> other) {
         int idx;
-        if ((idx = k8s.indexOf(node)) >= 0) return new String[]{"k8s", String.valueOf(idx)};
-        if ((idx = compose.indexOf(node)) >= 0) return new String[]{"compose", String.valueOf(idx)};
+        if ((idx = k8s.indexOf(node)) >= 0) return new String[]{PROP_K8S, String.valueOf(idx)};
+        if ((idx = compose.indexOf(node)) >= 0) return new String[]{PROP_COMPOSE, String.valueOf(idx)};
         if ((idx = tf.indexOf(node)) >= 0) return new String[]{"tf", String.valueOf(idx)};
-        if ((idx = docker.indexOf(node)) >= 0) return new String[]{"docker", String.valueOf(idx)};
+        if ((idx = docker.indexOf(node)) >= 0) return new String[]{PROP_DOCKER, String.valueOf(idx)};
         return new String[]{"other", String.valueOf(other.indexOf(node))};
     }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/graph/GraphStore.java b/src/main/java/io/github/randomcodespace/iq/graph/GraphStore.java
index 6b0a8bb8..1a6602af 100644
--- a/src/main/java/io/github/randomcodespace/iq/graph/GraphStore.java
+++ b/src/main/java/io/github/randomcodespace/iq/graph/GraphStore.java
@@ -34,6 +34,27 @@
 @Service
 @ConditionalOnBean(GraphRepository.class)
 public class GraphStore implements FlowDataSource {
+    private static final String PROP_CNT = "cnt";
+    private static final String PROP_CONNECTIONS = "connections";
+    private static final String PROP_EXT = "ext";
+    private static final String PROP_FILEPATH = "filePath";
+    private static final String PROP_ID = "id";
+    private static final String PROP_IDS = "ids";
+    private static final String PROP_KIND = "kind";
+    private static final String PROP_KINDS = "kinds";
+    private static final String PROP_LABEL = "label";
+    private static final String PROP_LAYER = "layer";
+    private static final String PROP_LIMIT = "limit";
+    private static final String PROP_METHOD = "method";
+    private static final String PROP_MODULE = "module";
+    private static final String PROP_NODEID = "nodeId";
+    private static final String PROP_OFFSET = "offset";
+    private static final String PROP_SOURCE = "source";
+    private static final String PROP_SOURCEID = "sourceId";
+    private static final String PROP_TARGET = "target";
+    private static final String PROP_TARGETID = "targetId";
+    private static final String PROP_TEXT = "text";
+
 
     private static final Logger log = LoggerFactory.getLogger(GraphStore.class);
 
@@ -79,7 +100,7 @@ public void bulkSave(List<CodeNode> nodes) {
             try (Transaction tx = graphDb.beginTx()) {
                 var result = tx.execute(
                         "MATCH (n) WITH n LIMIT 5000 DETACH DELETE n RETURN count(*) AS cnt");
-                deleted = result.hasNext() ? ((Number) result.next().get("cnt")).intValue() : 0;
+                deleted = result.hasNext() ? ((Number) result.next().get(PROP_CNT)).intValue() : 0;
                 tx.commit();
             }
         } while (deleted > 0);
@@ -147,10 +168,10 @@ public void bulkSave(List<CodeNode> nodes) {
                     continue;
                 }
                 edgeBatch.add(Map.of(
-                        "sourceId", sourceId,
-                        "targetId", targetId,
+                        PROP_SOURCEID, sourceId,
+                        PROP_TARGETID, targetId,
                         "edgeId", edge.getId(),
-                        "kind", edge.getKind().getValue()
+                        PROP_KIND, edge.getKind().getValue()
                 ));
                 created++;
             }
@@ -178,15 +199,15 @@ public void bulkSave(List<CodeNode> nodes) {
     /** Convert a CodeNode to a flat property map for Cypher SET. */
     private Map<String, Object> nodeToProps(CodeNode node) {
         Map<String, Object> props = new HashMap<>();
-        props.put("id", node.getId());
-        props.put("kind", node.getKind().getValue());
-        props.put("label", node.getLabel());
+        props.put(PROP_ID, node.getId());
+        props.put(PROP_KIND, node.getKind().getValue());
+        props.put(PROP_LABEL, node.getLabel());
         if (node.getFqn() != null) props.put("fqn", node.getFqn());
-        if (node.getModule() != null) props.put("module", node.getModule());
-        if (node.getFilePath() != null) props.put("filePath", node.getFilePath());
+        if (node.getModule() != null) props.put(PROP_MODULE, node.getModule());
+        if (node.getFilePath() != null) props.put(PROP_FILEPATH, node.getFilePath());
         if (node.getLineStart() != null) props.put("lineStart", node.getLineStart());
         if (node.getLineEnd() != null) props.put("lineEnd", node.getLineEnd());
-        if (node.getLayer() != null) props.put("layer", node.getLayer());
+        if (node.getLayer() != null) props.put(PROP_LAYER, node.getLayer());
         if (node.getAnnotations() != null && !node.getAnnotations().isEmpty()) {
             props.put("annotations", String.join(",", node.getAnnotations()));
         }
@@ -208,7 +229,7 @@ private Map<String, Object> nodeToProps(CodeNode node) {
     public Optional<CodeNode> findById(String id) {
         try (Transaction tx = graphDb.beginTx()) {
             var result = tx.execute(
-                    "MATCH (n:CodeNode {id: $id}) RETURN n", Map.of("id", id));
+                    "MATCH (n:CodeNode {id: $id}) RETURN n", Map.of(PROP_ID, id));
             if (result.hasNext()) {
                 var neo4jNode = (org.neo4j.graphdb.Node) result.next().get("n");
                 CodeNode node = nodeFromNeo4j(neo4jNode);
@@ -235,36 +256,36 @@ public List<CodeNode> findAll() {
 
     public List<CodeNode> findByKind(NodeKind kind) {
         return queryNodes("MATCH (n:CodeNode) WHERE n.kind = $kind RETURN n",
-                Map.of("kind", kind.getValue()));
+                Map.of(PROP_KIND, kind.getValue()));
     }
 
     public List<CodeNode> findByLayer(String layer) {
         return queryNodes("MATCH (n:CodeNode) WHERE n.layer = $layer RETURN n",
-                Map.of("layer", layer));
+                Map.of(PROP_LAYER, layer));
     }
 
     public List<CodeNode> findByModule(String module) {
         return queryNodes("MATCH (n:CodeNode) WHERE n.module = $module RETURN n",
-                Map.of("module", module));
+                Map.of(PROP_MODULE, module));
     }
 
     public List<CodeNode> findByFilePath(String filePath) {
         return queryNodes("MATCH (n:CodeNode) WHERE n.filePath = $filePath RETURN n",
-                Map.of("filePath", filePath));
+                Map.of(PROP_FILEPATH, filePath));
     }
 
     public List<CodeNode> search(String text) {
         return queryNodes(
                 "CALL db.index.fulltext.queryNodes('search_index', $text) "
                         + "YIELD node RETURN node AS n",
-                Map.of("text", toLuceneQuery(text)));
+                Map.of(PROP_TEXT, toLuceneQuery(text)));
     }
 
     public List<CodeNode> search(String text, int limit) {
         return queryNodes(
                 "CALL db.index.fulltext.queryNodes('search_index', $text) "
                         + "YIELD node RETURN node AS n LIMIT $limit",
-                Map.of("text", toLuceneQuery(text), "limit", limit));
+                Map.of(PROP_TEXT, toLuceneQuery(text), PROP_LIMIT, limit));
     }
 
     /**
@@ -276,7 +297,7 @@ public List<CodeNode> searchLexical(String text, int limit) {
         return queryNodes(
                 "CALL db.index.fulltext.queryNodes('lexical_index', $text) "
                         + "YIELD node RETURN node AS n LIMIT $limit",
-                Map.of("text", toLuceneQuery(text), "limit", limit));
+                Map.of(PROP_TEXT, toLuceneQuery(text), PROP_LIMIT, limit));
     }
 
     /**
@@ -308,7 +329,7 @@ private static String toLuceneQuery(String text) {
     public List<CodeNode> findNeighbors(String nodeId) {
         return queryNodes(
                 "MATCH (n:CodeNode)-[r]-(m:CodeNode) WHERE n.id = $nodeId RETURN m",
-                Map.of("nodeId", nodeId));
+                Map.of(PROP_NODEID, nodeId));
     }
 
     /**
@@ -326,7 +347,7 @@ public Map<String, List<CodeNode>> findEndpointNeighborsBatch(List<String> nodeI
                             + "MATCH (n:CodeNode {id: nid})-[]-(ep:CodeNode) "
                             + "WHERE ep.kind IN $epKinds "
                             + "RETURN nid AS matchId, ep",
-                    Map.of("ids", nodeIds, "epKinds", epKinds));
+                    Map.of(PROP_IDS, nodeIds, "epKinds", epKinds));
             while (qr.hasNext()) {
                 var row = qr.next();
                 String matchId = (String) row.get("matchId");
@@ -341,20 +362,20 @@ public Map<String, List<CodeNode>> findEndpointNeighborsBatch(List<String> nodeI
     public List<CodeNode> findOutgoingNeighbors(String nodeId) {
         return queryNodes(
                 "MATCH (n:CodeNode)-[r]->(m:CodeNode) WHERE n.id = $nodeId RETURN m",
-                Map.of("nodeId", nodeId));
+                Map.of(PROP_NODEID, nodeId));
     }
 
     public List<CodeNode> findIncomingNeighbors(String nodeId) {
         return queryNodes(
                 "MATCH (n:CodeNode)<-[r]-(m:CodeNode) WHERE n.id = $nodeId RETURN m",
-                Map.of("nodeId", nodeId));
+                Map.of(PROP_NODEID, nodeId));
     }
 
     public long count() {
         try (Transaction tx = graphDb.beginTx()) {
             var result = tx.execute("MATCH (n:CodeNode) RETURN count(n) AS cnt");
             if (result.hasNext()) {
-                return ((Number) result.next().get("cnt")).longValue();
+                return ((Number) result.next().get(PROP_CNT)).longValue();
             }
             return 0;
         }
@@ -367,10 +388,10 @@ public List<String> findShortestPath(String source, String target) {
             var result = tx.execute(
                     "MATCH p = shortestPath((a:CodeNode {id: $source})-[*..20]-(b:CodeNode {id: $target})) "
                             + "RETURN [n IN nodes(p) | n.id] AS ids",
-                    Map.of("source", source, "target", target));
+                    Map.of(PROP_SOURCE, source, PROP_TARGET, target));
             if (result.hasNext()) {
                 @SuppressWarnings("unchecked")
-                List<String> ids = (List<String>) result.next().get("ids");
+                List<String> ids = (List<String>) result.next().get(PROP_IDS);
                 return ids;
             }
             return List.of();
@@ -386,7 +407,7 @@ public List<CodeNode> findEgoGraph(String center, int radius) {
     public List<CodeNode> traceImpact(String nodeId, int depth) {
         return queryNodes(
                 "MATCH (a:CodeNode {id: $nodeId})-[:RELATES_TO*1..$depth]->(b:CodeNode) RETURN DISTINCT b",
-                Map.of("nodeId", nodeId, "depth", depth));
+                Map.of(PROP_NODEID, nodeId, "depth", depth));
     }
 
     public List<List<String>> findCycles(int limit) {
@@ -395,10 +416,10 @@ public List<List<String>> findCycles(int limit) {
             var result = tx.execute(
                     "MATCH p = (a:CodeNode)-[:RELATES_TO*2..10]->(a) "
                             + "RETURN [n IN nodes(p) | n.id] AS ids LIMIT $limit",
-                    Map.of("limit", limit));
+                    Map.of(PROP_LIMIT, limit));
             while (result.hasNext()) {
                 @SuppressWarnings("unchecked")
-                List<String> ids = (List<String>) result.next().get("ids");
+                List<String> ids = (List<String>) result.next().get(PROP_IDS);
                 cycles.add(ids);
             }
         }
@@ -409,21 +430,21 @@ public List<CodeNode> findConsumers(String targetId) {
         return queryNodes(
                 "MATCH (n:CodeNode)<-[r:RELATES_TO]-(m:CodeNode) "
                         + "WHERE n.id = $targetId AND r.kind IN ['consumes', 'listens'] RETURN m",
-                Map.of("targetId", targetId));
+                Map.of(PROP_TARGETID, targetId));
     }
 
     public List<CodeNode> findProducers(String targetId) {
         return queryNodes(
                 "MATCH (n:CodeNode)<-[r:RELATES_TO]-(m:CodeNode) "
                         + "WHERE n.id = $targetId AND r.kind IN ['produces', 'publishes'] RETURN m",
-                Map.of("targetId", targetId));
+                Map.of(PROP_TARGETID, targetId));
     }
 
     public List<CodeNode> findCallers(String targetId) {
         return queryNodes(
                 "MATCH (n:CodeNode)<-[r:RELATES_TO]-(m:CodeNode) "
                         + "WHERE n.id = $targetId AND r.kind = 'calls' RETURN m",
-                Map.of("targetId", targetId));
+                Map.of(PROP_TARGETID, targetId));
     }
 
     public List<CodeNode> findDependencies(String moduleId) {
@@ -443,22 +464,22 @@ public List<CodeNode> findDependents(String moduleId) {
     public List<CodeNode> findByKindPaginated(String kind, int offset, int limit) {
         return queryNodes(
                 "MATCH (n:CodeNode) WHERE n.kind = $kind RETURN n SKIP $offset LIMIT $limit",
-                Map.of("kind", kind, "offset", offset, "limit", limit));
+                Map.of(PROP_KIND, kind, PROP_OFFSET, offset, PROP_LIMIT, limit));
     }
 
     public List<CodeNode> findAllPaginated(int offset, int limit) {
         return queryNodes(
                 "MATCH (n:CodeNode) RETURN n SKIP $offset LIMIT $limit",
-                Map.of("offset", offset, "limit", limit));
+                Map.of(PROP_OFFSET, offset, PROP_LIMIT, limit));
     }
 
     public long countByKind(String kind) {
         try (Transaction tx = graphDb.beginTx()) {
             var result = tx.execute(
                     "MATCH (n:CodeNode) WHERE n.kind = $kind RETURN count(n) AS cnt",
-                    Map.of("kind", kind));
+                    Map.of(PROP_KIND, kind));
             if (result.hasNext()) {
-                return ((Number) result.next().get("cnt")).longValue();
+                return ((Number) result.next().get(PROP_CNT)).longValue();
             }
             return 0;
         }
@@ -470,7 +491,7 @@ public long countEdges() {
         try (Transaction tx = graphDb.beginTx()) {
             var result = tx.execute("MATCH ()-[r:RELATES_TO]->() RETURN count(r) AS cnt");
             if (result.hasNext()) {
-                return ((Number) result.next().get("cnt")).longValue();
+                return ((Number) result.next().get(PROP_CNT)).longValue();
             }
             return 0;
         }
@@ -482,7 +503,7 @@ public long countDistinctFiles() {
                     "MATCH (n:CodeNode) WHERE n.filePath IS NOT NULL AND n.filePath <> '' "
                             + "RETURN count(DISTINCT n.filePath) AS cnt");
             if (result.hasNext()) {
-                return ((Number) result.next().get("cnt")).longValue();
+                return ((Number) result.next().get(PROP_CNT)).longValue();
             }
             return 0;
         }
@@ -502,8 +523,8 @@ public List<Map<String, Object>> countByFileExtension() {
             while (result.hasNext()) {
                 var row = result.next();
                 Map<String, Object> m = new LinkedHashMap<>();
-                m.put("ext", row.get("ext"));
-                m.put("cnt", ((Number) row.get("cnt")).longValue());
+                m.put(PROP_EXT, row.get(PROP_EXT));
+                m.put(PROP_CNT, ((Number) row.get(PROP_CNT)).longValue());
                 rows.add(m);
             }
         }
@@ -517,8 +538,8 @@ public List<Map<String, Object>> countNodesByKind() {
             while (result.hasNext()) {
                 var row = result.next();
                 Map<String, Object> m = new LinkedHashMap<>();
-                m.put("kind", row.get("kind"));
-                m.put("cnt", ((Number) row.get("cnt")).longValue());
+                m.put(PROP_KIND, row.get(PROP_KIND));
+                m.put(PROP_CNT, ((Number) row.get(PROP_CNT)).longValue());
                 rows.add(m);
             }
         }
@@ -533,8 +554,8 @@ public List<Map<String, Object>> countNodesByLayer() {
             while (result.hasNext()) {
                 var row = result.next();
                 Map<String, Object> m = new LinkedHashMap<>();
-                m.put("layer", row.get("layer"));
-                m.put("cnt", ((Number) row.get("cnt")).longValue());
+                m.put(PROP_LAYER, row.get(PROP_LAYER));
+                m.put(PROP_CNT, ((Number) row.get(PROP_CNT)).longValue());
                 rows.add(m);
             }
         }
@@ -548,14 +569,14 @@ public List<Map<String, Object>> findEdgesPaginated(int offset, int limit) {
                     "MATCH (s:CodeNode)-[r:RELATES_TO]->(t:CodeNode) "
                             + "RETURN r.id AS id, r.kind AS kind, s.id AS sourceId, t.id AS targetId "
                             + "SKIP $offset LIMIT $limit",
-                    Map.of("offset", offset, "limit", limit));
+                    Map.of(PROP_OFFSET, offset, PROP_LIMIT, limit));
             while (result.hasNext()) {
                 var row = result.next();
                 Map<String, Object> m = new LinkedHashMap<>();
-                m.put("id", row.get("id"));
-                m.put("kind", row.get("kind"));
-                m.put("sourceId", row.get("sourceId"));
-                m.put("targetId", row.get("targetId"));
+                m.put(PROP_ID, row.get(PROP_ID));
+                m.put(PROP_KIND, row.get(PROP_KIND));
+                m.put(PROP_SOURCEID, row.get(PROP_SOURCEID));
+                m.put(PROP_TARGETID, row.get(PROP_TARGETID));
                 rows.add(m);
             }
         }
@@ -569,14 +590,14 @@ public List<Map<String, Object>> findEdgesByKindPaginated(String kind, int offse
                     "MATCH (s:CodeNode)-[r:RELATES_TO]->(t:CodeNode) WHERE r.kind = $kind "
                             + "RETURN r.id AS id, r.kind AS kind, s.id AS sourceId, t.id AS targetId "
                             + "SKIP $offset LIMIT $limit",
-                    Map.of("kind", kind, "offset", offset, "limit", limit));
+                    Map.of(PROP_KIND, kind, PROP_OFFSET, offset, PROP_LIMIT, limit));
             while (result.hasNext()) {
                 var row = result.next();
                 Map<String, Object> m = new LinkedHashMap<>();
-                m.put("id", row.get("id"));
-                m.put("kind", row.get("kind"));
-                m.put("sourceId", row.get("sourceId"));
-                m.put("targetId", row.get("targetId"));
+                m.put(PROP_ID, row.get(PROP_ID));
+                m.put(PROP_KIND, row.get(PROP_KIND));
+                m.put(PROP_SOURCEID, row.get(PROP_SOURCEID));
+                m.put(PROP_TARGETID, row.get(PROP_TARGETID));
                 rows.add(m);
             }
         }
@@ -599,11 +620,11 @@ public FilePathResult getFilePathsWithCounts(int maxFiles) {
                             + "RETURN n.filePath AS filePath, count(n) AS nodeCount "
                             + "ORDER BY n.filePath "
                             + "LIMIT $limit",
-                    Map.of("limit", (long) (maxFiles + 1)));
+                    Map.of(PROP_LIMIT, (long) (maxFiles + 1)));
             while (result.hasNext()) {
                 var row = result.next();
                 Map<String, Object> m = new LinkedHashMap<>();
-                m.put("filePath", row.get("filePath"));
+                m.put(PROP_FILEPATH, row.get(PROP_FILEPATH));
                 m.put("nodeCount", ((Number) row.get("nodeCount")).longValue());
                 rows.add(m);
             }
@@ -619,9 +640,9 @@ public long countEdgesByKind(String kind) {
         try (Transaction tx = graphDb.beginTx()) {
             var result = tx.execute(
                     "MATCH ()-[r:RELATES_TO]->() WHERE r.kind = $kind RETURN count(r) AS cnt",
-                    Map.of("kind", kind));
+                    Map.of(PROP_KIND, kind));
             if (result.hasNext()) {
-                return ((Number) result.next().get("cnt")).longValue();
+                return ((Number) result.next().get(PROP_CNT)).longValue();
             }
             return 0;
         }
@@ -651,11 +672,11 @@ public List<CodeNode> findNodesWithoutIncomingSemantic(List<String> kinds,
                         + "AND NOT n.kind IN $excludeKinds "
                         + "AND NOT EXISTS { MATCH (m)-[r:RELATES_TO]->(n) WHERE r.kind IN $semanticKinds } "
                         + "RETURN n SKIP $offset LIMIT $limit",
-                Map.of("kinds", kinds,
+                Map.of(PROP_KINDS, kinds,
                         "semanticKinds", semanticEdgeKinds,
                         "excludeKinds", excludeNodeKinds,
-                        "offset", offset,
-                        "limit", limit));
+                        PROP_OFFSET, offset,
+                        PROP_LIMIT, limit));
     }
 
     /**
@@ -668,7 +689,7 @@ public List<CodeNode> findNodesWithoutIncoming(List<String> kinds, int offset, i
                 "MATCH (n:CodeNode) WHERE n.kind IN $kinds "
                         + "AND NOT EXISTS { MATCH (m)-[:RELATES_TO]->(n) } "
                         + "RETURN n SKIP $offset LIMIT $limit",
-                Map.of("kinds", kinds, "offset", offset, "limit", limit));
+                Map.of(PROP_KINDS, kinds, PROP_OFFSET, offset, PROP_LIMIT, limit));
     }
 
     // --- Topology queries ---
@@ -697,10 +718,10 @@ public Map<String, Object> getTopology() {
             while (result.hasNext()) {
                 var row = result.next();
                 Map<String, Object> svc = new LinkedHashMap<>();
-                svc.put("id", row.get("id"));
-                svc.put("label", row.get("label"));
-                svc.put("kind", row.get("kind"));
-                svc.put("layer", row.get("layer"));
+                svc.put(PROP_ID, row.get(PROP_ID));
+                svc.put(PROP_LABEL, row.get(PROP_LABEL));
+                svc.put(PROP_KIND, row.get(PROP_KIND));
+                svc.put(PROP_LAYER, row.get(PROP_LAYER));
                 Object nc = row.get("node_count");
                 svc.put("node_count", nc instanceof Number n ? n.longValue() : 0L);
                 services.add(svc);
@@ -712,15 +733,15 @@ public Map<String, Object> getTopology() {
             var result = tx.execute(
                     "MATCH (n:CodeNode) WHERE n.kind IN $kinds "
                             + "RETURN n.id AS id, n.label AS label, n.kind AS kind",
-                    Map.of("kinds", infraKinds));
+                    Map.of(PROP_KINDS, infraKinds));
             while (result.hasNext()) {
                 var row = result.next();
-                String id = (String) row.get("id");
-                String kind = (String) row.get("kind");
+                String id = (String) row.get(PROP_ID);
+                String kind = (String) row.get(PROP_KIND);
                 Map<String, Object> infra = new LinkedHashMap<>();
-                infra.put("id", id);
-                infra.put("label", row.get("label"));
-                infra.put("kind", kind);
+                infra.put(PROP_ID, id);
+                infra.put(PROP_LABEL, row.get(PROP_LABEL));
+                infra.put(PROP_KIND, kind);
                 // Derive type from id prefix (e.g., "postgresql:orders-db" → "postgresql")
                 if (id != null && id.contains(":")) {
                     infra.put("type", id.split(":", 2)[0]);
@@ -737,14 +758,14 @@ public Map<String, Object> getTopology() {
                     "MATCH (s:CodeNode)-[r:RELATES_TO]->(t:CodeNode) "
                             + "WHERE s.kind = 'service' AND t.kind IN $kinds "
                             + "RETURN s.id AS source, t.id AS target, r.kind AS kind, count(r) AS cnt",
-                    Map.of("kinds", infraKinds));
+                    Map.of(PROP_KINDS, infraKinds));
             while (result.hasNext()) {
                 var row = result.next();
                 Map<String, Object> conn = new LinkedHashMap<>();
-                conn.put("source", row.get("source"));
-                conn.put("target", row.get("target"));
-                conn.put("kind", row.get("kind"));
-                Object cnt = row.get("cnt");
+                conn.put(PROP_SOURCE, row.get(PROP_SOURCE));
+                conn.put(PROP_TARGET, row.get(PROP_TARGET));
+                conn.put(PROP_KIND, row.get(PROP_KIND));
+                Object cnt = row.get(PROP_CNT);
                 conn.put("count", cnt instanceof Number n ? n.longValue() : 0L);
                 connections.add(conn);
             }
@@ -753,7 +774,7 @@ public Map<String, Object> getTopology() {
         Map<String, Object> topology = new LinkedHashMap<>();
         topology.put("services", services);
         topology.put("infrastructure", infrastructure);
-        topology.put("connections", connections);
+        topology.put(PROP_CONNECTIONS, connections);
         return topology;
     }
 
@@ -769,7 +790,7 @@ public Map<String, Object> computeAggregateStats() {
         result.put("languages", computeLanguageStats());
         result.put("frameworks", computeFrameworkStats());
         result.put("infra", computeInfraStats());
-        result.put("connections", computeConnectionStats());
+        result.put(PROP_CONNECTIONS, computeConnectionStats());
         result.put("auth", computeAuthStats());
         result.put("architecture", computeArchitectureStats());
         return result;
@@ -784,7 +805,7 @@ public Map<String, Object> computeAggregateCategoryStats(String category) {
             case "languages" -> computeLanguageStats();
             case "frameworks" -> computeFrameworkStats();
             case "infra" -> computeInfraStats();
-            case "connections" -> computeConnectionStats();
+            case PROP_CONNECTIONS -> computeConnectionStats();
             case "auth" -> computeAuthStats();
             case "architecture" -> computeArchitectureStats();
             default -> null;
@@ -795,13 +816,13 @@ private Map<String, Object> computeGraphStats() {
         Map<String, Object> graph = new LinkedHashMap<>();
         try (Transaction tx = graphDb.beginTx()) {
             var r1 = tx.execute("MATCH (n:CodeNode) RETURN count(n) AS cnt");
-            graph.put("nodes", r1.hasNext() ? ((Number) r1.next().get("cnt")).longValue() : 0L);
+            graph.put("nodes", r1.hasNext() ? ((Number) r1.next().get(PROP_CNT)).longValue() : 0L);
             var r2 = tx.execute("MATCH ()-[r:RELATES_TO]->() RETURN count(r) AS cnt");
-            graph.put("edges", r2.hasNext() ? ((Number) r2.next().get("cnt")).longValue() : 0L);
+            graph.put("edges", r2.hasNext() ? ((Number) r2.next().get(PROP_CNT)).longValue() : 0L);
             var r3 = tx.execute(
                     "MATCH (n:CodeNode) WHERE n.filePath IS NOT NULL AND n.filePath <> '' "
                             + "RETURN count(DISTINCT n.filePath) AS cnt");
-            graph.put("files", r3.hasNext() ? ((Number) r3.next().get("cnt")).longValue() : 0L);
+            graph.put("files", r3.hasNext() ? ((Number) r3.next().get(PROP_CNT)).longValue() : 0L);
         }
         return graph;
     }
@@ -816,16 +837,16 @@ private Map<String, Object> computeLanguageStats() {
                 var row = result.next();
                 String lang = String.valueOf(row.get("lang")).trim();
                 if (!lang.isBlank()) {
-                    langCounts.merge(lang, ((Number) row.get("cnt")).longValue(), Long::sum);
+                    langCounts.merge(lang, ((Number) row.get(PROP_CNT)).longValue(), Long::sum);
                 }
             }
         }
         if (langCounts.isEmpty()) {
             for (Map<String, Object> row : countByFileExtension()) {
-                String ext = String.valueOf(row.get("ext")).trim().toLowerCase();
+                String ext = String.valueOf(row.get(PROP_EXT)).trim().toLowerCase();
                 String lang = extensionToLanguage(ext);
                 if (lang != null) {
-                    langCounts.merge(lang, ((Number) row.get("cnt")).longValue(), Long::sum);
+                    langCounts.merge(lang, ((Number) row.get(PROP_CNT)).longValue(), Long::sum);
                 }
             }
         }
@@ -842,7 +863,7 @@ private Map<String, Object> computeFrameworkStats() {
                 var row = result.next();
                 String fw = String.valueOf(row.get("fw")).trim();
                 if (!fw.isBlank()) {
-                    fwCounts.merge(fw, ((Number) row.get("cnt")).longValue(), Long::sum);
+                    fwCounts.merge(fw, ((Number) row.get(PROP_CNT)).longValue(), Long::sum);
                 }
             }
         }
@@ -861,7 +882,7 @@ private Map<String, Object> computeInfraStats() {
                 var row = result.next();
                 String dbType = normalizeDbType(String.valueOf(row.get("dbType")));
                 if (dbType != null) {
-                    databases.merge(dbType, ((Number) row.get("cnt")).longValue(), Long::sum);
+                    databases.merge(dbType, ((Number) row.get(PROP_CNT)).longValue(), Long::sum);
                 }
             }
         }
@@ -874,7 +895,7 @@ private Map<String, Object> computeInfraStats() {
                             + "RETURN coalesce(n.prop_protocol, n.label, 'unknown') AS protocol, count(n) AS cnt");
             while (result.hasNext()) {
                 var row = result.next();
-                messaging.merge(String.valueOf(row.get("protocol")), ((Number) row.get("cnt")).longValue(), Long::sum);
+                messaging.merge(String.valueOf(row.get("protocol")), ((Number) row.get(PROP_CNT)).longValue(), Long::sum);
             }
         }
         infra.put("messaging", sortByValueDesc(messaging));
@@ -886,7 +907,7 @@ private Map<String, Object> computeInfraStats() {
                             + "RETURN coalesce(n.prop_resource_type, n.label, 'unknown') AS resType, count(n) AS cnt");
             while (result.hasNext()) {
                 var row = result.next();
-                cloud.merge(String.valueOf(row.get("resType")), ((Number) row.get("cnt")).longValue(), Long::sum);
+                cloud.merge(String.valueOf(row.get("resType")), ((Number) row.get(PROP_CNT)).longValue(), Long::sum);
             }
         }
         infra.put("cloud", sortByValueDesc(cloud));
@@ -904,7 +925,7 @@ private Map<String, Object> computeConnectionStats() {
             Map<String, Long> restByMethod = new TreeMap<>();
             while (restResult.hasNext()) {
                 var row = restResult.next();
-                restByMethod.put(String.valueOf(row.get("method")), ((Number) row.get("cnt")).longValue());
+                restByMethod.put(String.valueOf(row.get(PROP_METHOD)), ((Number) row.get(PROP_CNT)).longValue());
             }
             long restTotal = restByMethod.values().stream().mapToLong(Long::longValue).sum();
             Map<String, Object> rest = new LinkedHashMap<>();
@@ -914,19 +935,19 @@ private Map<String, Object> computeConnectionStats() {
 
             var grpcResult = tx.execute(
                     "MATCH (n:CodeNode) WHERE n.kind = 'endpoint' AND n.prop_protocol = 'grpc' RETURN count(n) AS cnt");
-            connections.put("grpc", grpcResult.hasNext() ? ((Number) grpcResult.next().get("cnt")).longValue() : 0L);
+            connections.put("grpc", grpcResult.hasNext() ? ((Number) grpcResult.next().get(PROP_CNT)).longValue() : 0L);
 
             var wsResult = tx.execute(
                     "MATCH (n:CodeNode) WHERE n.kind = 'websocket_endpoint' RETURN count(n) AS cnt");
-            connections.put("websocket", wsResult.hasNext() ? ((Number) wsResult.next().get("cnt")).longValue() : 0L);
+            connections.put("websocket", wsResult.hasNext() ? ((Number) wsResult.next().get(PROP_CNT)).longValue() : 0L);
 
             var prodResult = tx.execute(
                     "MATCH ()-[r:RELATES_TO]->() WHERE r.kind IN ['produces', 'publishes'] RETURN count(r) AS cnt");
-            connections.put("producers", prodResult.hasNext() ? ((Number) prodResult.next().get("cnt")).longValue() : 0L);
+            connections.put("producers", prodResult.hasNext() ? ((Number) prodResult.next().get(PROP_CNT)).longValue() : 0L);
 
             var consResult = tx.execute(
                     "MATCH ()-[r:RELATES_TO]->() WHERE r.kind IN ['consumes', 'listens'] RETURN count(r) AS cnt");
-            connections.put("consumers", consResult.hasNext() ? ((Number) consResult.next().get("cnt")).longValue() : 0L);
+            connections.put("consumers", consResult.hasNext() ? ((Number) consResult.next().get(PROP_CNT)).longValue() : 0L);
         }
         return connections;
     }
@@ -941,7 +962,7 @@ private Map<String, Object> computeAuthStats() {
                 var row = guardResult.next();
                 String authType = String.valueOf(row.get("authType")).trim();
                 if (!authType.isBlank()) {
-                    authCounts.merge(authType, ((Number) row.get("cnt")).longValue(), Long::sum);
+                    authCounts.merge(authType, ((Number) row.get(PROP_CNT)).longValue(), Long::sum);
                 }
             }
             var fwResult = tx.execute(
@@ -952,7 +973,7 @@ private Map<String, Object> computeAuthStats() {
                 String fw = String.valueOf(row.get("fw")).trim();
                 String authType = fw.substring("auth:".length()).trim();
                 if (!authType.isEmpty()) {
-                    authCounts.merge(authType, ((Number) row.get("cnt")).longValue(), Long::sum);
+                    authCounts.merge(authType, ((Number) row.get(PROP_CNT)).longValue(), Long::sum);
                 }
             }
         }
@@ -964,18 +985,18 @@ private Map<String, Object> computeArchitectureStats() {
         Map<String, String> kindToLabel = Map.of(
                 "class", "classes", "interface", "interfaces",
                 "abstract_class", "abstract_classes", "enum", "enums",
-                "annotation_type", "annotation_types", "module", "modules",
-                "method", "methods");
+                "annotation_type", "annotation_types", PROP_MODULE, "modules",
+                PROP_METHOD, "methods");
         List<String> archKinds = List.of("class", "interface", "abstract_class", "enum",
-                "annotation_type", "module", "method");
+                "annotation_type", PROP_MODULE, PROP_METHOD);
         try (Transaction tx = graphDb.beginTx()) {
             var result = tx.execute(
                     "MATCH (n:CodeNode) WHERE n.kind IN $kinds RETURN n.kind AS kind, count(n) AS cnt",
-                    Map.of("kinds", archKinds));
+                    Map.of(PROP_KINDS, archKinds));
             while (result.hasNext()) {
                 var row = result.next();
-                String kind = (String) row.get("kind");
-                long cnt = ((Number) row.get("cnt")).longValue();
+                String kind = (String) row.get(PROP_KIND);
+                long cnt = ((Number) row.get(PROP_CNT)).longValue();
                 if (cnt > 0) {
                     arch.put(kindToLabel.getOrDefault(kind, kind), cnt);
                 }
@@ -1070,10 +1091,10 @@ private void hydrateEdges(List<CodeNode> nodes) {
                             + "RETURN r.id AS id, r.kind AS kind, s.id AS sourceId, t.id AS targetId");
             while (result.hasNext()) {
                 var row = result.next();
-                String sourceId = (String) row.get("sourceId");
-                String targetId = (String) row.get("targetId");
-                String edgeId = (String) row.get("id");
-                String kindStr = (String) row.get("kind");
+                String sourceId = (String) row.get(PROP_SOURCEID);
+                String targetId = (String) row.get(PROP_TARGETID);
+                String edgeId = (String) row.get(PROP_ID);
+                String kindStr = (String) row.get(PROP_KIND);
 
                 CodeNode source = nodeById.get(sourceId);
                 CodeNode target = nodeById.get(targetId);
@@ -1098,12 +1119,12 @@ private void hydrateEdgesForNode(Transaction tx, CodeNode node) {
         var result = tx.execute(
                 "MATCH (s:CodeNode {id: $nodeId})-[r:RELATES_TO]->(t:CodeNode) "
                         + "RETURN r.id AS id, r.kind AS kind, t.id AS targetId, t",
-                Map.of("nodeId", node.getId()));
+                Map.of(PROP_NODEID, node.getId()));
         while (result.hasNext()) {
             var row = result.next();
-            String edgeId = (String) row.get("id");
-            String kindStr = (String) row.get("kind");
-            String targetId = (String) row.get("targetId");
+            String edgeId = (String) row.get(PROP_ID);
+            String kindStr = (String) row.get(PROP_KIND);
+            String targetId = (String) row.get(PROP_TARGETID);
             EdgeKind edgeKind;
             try {
                 edgeKind = EdgeKind.fromValue(kindStr);
@@ -1122,16 +1143,16 @@ private void hydrateEdgesForNode(Transaction tx, CodeNode node) {
      * This is the key to avoiding OOM — we read only scalar properties.
      */
     private static CodeNode nodeFromNeo4j(org.neo4j.graphdb.Node neo4jNode) {
-        String id = (String) neo4jNode.getProperty("id", null);
-        String kindStr = (String) neo4jNode.getProperty("kind", null);
+        String id = (String) neo4jNode.getProperty(PROP_ID, null);
+        String kindStr = (String) neo4jNode.getProperty(PROP_KIND, null);
         NodeKind kind = kindStr != null ? NodeKind.fromValue(kindStr) : NodeKind.MODULE;
-        String label = (String) neo4jNode.getProperty("label", "");
+        String label = (String) neo4jNode.getProperty(PROP_LABEL, "");
 
         CodeNode node = new CodeNode(id, kind, label);
         node.setFqn((String) neo4jNode.getProperty("fqn", null));
-        node.setModule((String) neo4jNode.getProperty("module", null));
-        node.setFilePath((String) neo4jNode.getProperty("filePath", null));
-        node.setLayer((String) neo4jNode.getProperty("layer", null));
+        node.setModule((String) neo4jNode.getProperty(PROP_MODULE, null));
+        node.setFilePath((String) neo4jNode.getProperty(PROP_FILEPATH, null));
+        node.setLayer((String) neo4jNode.getProperty(PROP_LAYER, null));
 
         Object lineStart = neo4jNode.getProperty("lineStart", null);
         if (lineStart instanceof Number n) node.setLineStart(n.intValue());
diff --git a/src/main/java/io/github/randomcodespace/iq/intelligence/RepositoryIdentity.java b/src/main/java/io/github/randomcodespace/iq/intelligence/RepositoryIdentity.java
index 622e4235..31ce5aa4 100644
--- a/src/main/java/io/github/randomcodespace/iq/intelligence/RepositoryIdentity.java
+++ b/src/main/java/io/github/randomcodespace/iq/intelligence/RepositoryIdentity.java
@@ -18,15 +18,17 @@ public record RepositoryIdentity(
         String branch,
         Instant buildTimestamp
 ) {
+    private static final String PROP_HEAD = "HEAD";
+
     /**
      * Resolve repository identity from a local path using git commands.
      * Fields that cannot be determined are set to null gracefully.
      */
     public static RepositoryIdentity resolve(java.nio.file.Path repoPath) {
         String repoUrl   = runGit(repoPath, "remote", "get-url", "origin");
-        String commitSha = runGit(repoPath, "rev-parse", "HEAD");
-        String branch    = runGit(repoPath, "rev-parse", "--abbrev-ref", "HEAD");
-        // Detached HEAD produces "HEAD" rather than a branch name — normalise to null
+        String commitSha = runGit(repoPath, "rev-parse", PROP_HEAD);
+        String branch    = runGit(repoPath, "rev-parse", "--abbrev-ref", PROP_HEAD);
+        // Detached HEAD produces PROP_HEAD rather than a branch name — normalise to null
         if ("HEAD".equals(branch)) branch = null;
         return new RepositoryIdentity(repoUrl, commitSha, branch, Instant.now());
     }
diff --git a/src/main/java/io/github/randomcodespace/iq/intelligence/evidence/EvidencePackAssembler.java b/src/main/java/io/github/randomcodespace/iq/intelligence/evidence/EvidencePackAssembler.java
index 876837be..c364550b 100644
--- a/src/main/java/io/github/randomcodespace/iq/intelligence/evidence/EvidencePackAssembler.java
+++ b/src/main/java/io/github/randomcodespace/iq/intelligence/evidence/EvidencePackAssembler.java
@@ -34,6 +34,8 @@
 @Service
 @Profile("serving")
 public class EvidencePackAssembler {
+    private static final String PROP_UNKNOWN = "unknown";
+
 
     private final LexicalQueryService lexicalQueryService;
     private final SnippetStore snippetStore;
@@ -79,7 +81,7 @@ public EvidencePack assemble(EvidencePackRequest request, ArtifactMetadata artif
         // Determine language from filePath when available (for query planner)
         String language = request.filePath() != null
                 ? inferLanguage(request.filePath())
-                : "unknown";
+                : PROP_UNKNOWN;
 
         // Plan the query
         QueryPlan plan = queryPlanner.plan(QueryType.FIND_SYMBOL, language);
@@ -126,7 +128,7 @@ public EvidencePack assemble(EvidencePackRequest request, ArtifactMetadata artif
                     if (n.getFilePath() != null) m.put("filePath", n.getFilePath());
                     if (n.getLineStart() != null) m.put("lineStart", n.getLineStart());
                     if (n.getLineEnd() != null) m.put("lineEnd", n.getLineEnd());
-                    m.put("kind", n.getKind() != null ? n.getKind().getValue() : "unknown");
+                    m.put("kind", n.getKind() != null ? n.getKind().getValue() : PROP_UNKNOWN);
                     if (n.getProperties() != null) {
                         n.getProperties().forEach((k, v) -> {
                             if (k.startsWith("prov_") && v != null) m.put(k, v);
@@ -236,9 +238,9 @@ private CapabilityLevel deriveCapabilityLevel(QueryPlan plan) {
     }
 
     private static String inferLanguage(String filePath) {
-        if (filePath == null) return "unknown";
+        if (filePath == null) return PROP_UNKNOWN;
         int dot = filePath.lastIndexOf('.');
-        if (dot < 0) return "unknown";
+        if (dot < 0) return PROP_UNKNOWN;
         return switch (filePath.substring(dot + 1).toLowerCase()) {
             case "java"              -> "java";
             case "ts", "tsx"         -> "typescript";
@@ -247,7 +249,7 @@ private static String inferLanguage(String filePath) {
             case "go"                -> "go";
             case "rs"                -> "rust";
             case "cs"                -> "csharp";
-            default                  -> "unknown";
+            default                  -> PROP_UNKNOWN;
         };
     }
 }
diff --git a/src/main/java/io/github/randomcodespace/iq/intelligence/extractor/LanguageEnricher.java b/src/main/java/io/github/randomcodespace/iq/intelligence/extractor/LanguageEnricher.java
index e49419b8..a3cae8d5 100644
--- a/src/main/java/io/github/randomcodespace/iq/intelligence/extractor/LanguageEnricher.java
+++ b/src/main/java/io/github/randomcodespace/iq/intelligence/extractor/LanguageEnricher.java
@@ -29,15 +29,18 @@
  */
 @Component
 public class LanguageEnricher {
+    private static final String PROP_JAVASCRIPT = "javascript";
+    private static final String PROP_TYPESCRIPT = "typescript";
+
 
     private static final Logger log = LoggerFactory.getLogger(LanguageEnricher.class);
 
     /**
      * Language alias map: normalises file-extension languages to extractor language keys.
-     * e.g. "javascript" nodes are handled by the "typescript" extractor.
+     * e.g. PROP_JAVASCRIPT nodes are handled by the PROP_TYPESCRIPT extractor.
      */
     private static final Map<String, String> LANGUAGE_ALIASES = Map.of(
-            "javascript", "typescript"
+            PROP_JAVASCRIPT, PROP_TYPESCRIPT
     );
 
     private final List<LanguageExtractor> extractors;
@@ -150,8 +153,8 @@ static String detectLanguage(String filePath) {
         if (dot < 0) return null;
         return switch (filePath.substring(dot + 1).toLowerCase()) {
             case "java" -> "java";
-            case "ts", "tsx" -> "typescript";
-            case "js", "jsx", "mjs", "cjs" -> "javascript";
+            case "ts", "tsx" -> PROP_TYPESCRIPT;
+            case "js", "jsx", "mjs", "cjs" -> PROP_JAVASCRIPT;
             case "py", "pyw" -> "python";
             case "go" -> "go";
             default -> null;
diff --git a/src/main/java/io/github/randomcodespace/iq/intelligence/lexical/SnippetStore.java b/src/main/java/io/github/randomcodespace/iq/intelligence/lexical/SnippetStore.java
index 7d147122..4c9aea45 100644
--- a/src/main/java/io/github/randomcodespace/iq/intelligence/lexical/SnippetStore.java
+++ b/src/main/java/io/github/randomcodespace/iq/intelligence/lexical/SnippetStore.java
@@ -17,6 +17,8 @@
  */
 @Component
 public class SnippetStore {
+    private static final String PROP_UNKNOWN = "unknown";
+
 
     /** Maximum lines in any extracted snippet. */
     public static final int MAX_LINES = 50;
@@ -83,9 +85,9 @@ public Optional<CodeSnippet> extract(CodeNode node, Path rootPath, int contextLi
     }
 
     static String inferLanguage(String filePath) {
-        if (filePath == null) return "unknown";
+        if (filePath == null) return PROP_UNKNOWN;
         int dot = filePath.lastIndexOf('.');
-        if (dot < 0) return "unknown";
+        if (dot < 0) return PROP_UNKNOWN;
         return switch (filePath.substring(dot + 1).toLowerCase()) {
             case "java"              -> "java";
             case "ts", "tsx"         -> "typescript";
@@ -98,7 +100,7 @@ static String inferLanguage(String filePath) {
                  "h", "hpp"          -> "cpp";
             case "kt"                -> "kotlin";
             case "scala", "sc"       -> "scala";
-            default                  -> "unknown";
+            default                  -> PROP_UNKNOWN;
         };
     }
 }
diff --git a/src/main/java/io/github/randomcodespace/iq/intelligence/query/CapabilityMatrix.java b/src/main/java/io/github/randomcodespace/iq/intelligence/query/CapabilityMatrix.java
index 6779478d..989a30a3 100644
--- a/src/main/java/io/github/randomcodespace/iq/intelligence/query/CapabilityMatrix.java
+++ b/src/main/java/io/github/randomcodespace/iq/intelligence/query/CapabilityMatrix.java
@@ -27,6 +27,14 @@
  * <p>This class is intentionally non-instantiable. Use the static {@link #get} methods.
  */
 public final class CapabilityMatrix {
+    private static final String PROP_CPP = "cpp";
+    private static final String PROP_CSHARP = "csharp";
+    private static final String PROP_GO = "go";
+    private static final String PROP_JAVASCRIPT = "javascript";
+    private static final String PROP_PYTHON = "python";
+    private static final String PROP_RUST = "rust";
+    private static final String PROP_TYPESCRIPT = "typescript";
+
 
     // ------------------------------------------------------------------
     // Language normalisation
@@ -34,7 +42,7 @@ public final class CapabilityMatrix {
 
     /** Languages with ANTLR or JavaParser AST-level support. */
     private static final Set<String> ANTLR_LANGUAGES =
-            Set.of("typescript", "javascript", "python", "go", "csharp", "rust", "cpp");
+            Set.of(PROP_TYPESCRIPT, PROP_JAVASCRIPT, PROP_PYTHON, PROP_GO, PROP_CSHARP, PROP_RUST, PROP_CPP);
 
     /** Languages with regex/text-only detection (no grammar). */
     private static final Set<String> LEXICAL_ONLY_LANGUAGES =
@@ -234,7 +242,7 @@ public static CapabilityLevel get(String language, CapabilityDimension dimension
     public static Map<String, Map<String, String>> asSerializableMap() {
         Map<String, Map<String, String>> result = new TreeMap<>();
         for (String lang : new String[]{
-                "java", "typescript", "javascript", "python", "go", "csharp", "rust", "cpp",
+                "java", PROP_TYPESCRIPT, PROP_JAVASCRIPT, PROP_PYTHON, PROP_GO, PROP_CSHARP, PROP_RUST, PROP_CPP,
                 "kotlin", "scala", "ruby", "php", "shell"}) {
             Map<CapabilityDimension, CapabilityLevel> caps = tableFor(lang);
             Map<String, String> row = new LinkedHashMap<>();
@@ -258,13 +266,13 @@ private static String normalise(String language) {
     private static Map<CapabilityDimension, CapabilityLevel> tableFor(String lang) {
         return switch (lang) {
             case "java"       -> JAVA_CAPS;
-            case "typescript" -> TYPESCRIPT_CAPS;
-            case "javascript" -> JAVASCRIPT_CAPS;
-            case "python"     -> PYTHON_CAPS;
-            case "go"         -> GO_CAPS;
-            case "csharp", "c#" -> CSHARP_CAPS;
-            case "cpp", "c++"   -> CPP_CAPS;
-            case "rust"       -> RUST_CAPS;
+            case PROP_TYPESCRIPT -> TYPESCRIPT_CAPS;
+            case PROP_JAVASCRIPT -> JAVASCRIPT_CAPS;
+            case PROP_PYTHON     -> PYTHON_CAPS;
+            case PROP_GO         -> GO_CAPS;
+            case PROP_CSHARP, "c#" -> CSHARP_CAPS;
+            case PROP_CPP, "c++"   -> CPP_CAPS;
+            case PROP_RUST       -> RUST_CAPS;
             default -> {
                 if (LEXICAL_ONLY_LANGUAGES.contains(lang)) yield LEXICAL_ONLY_CAPS;
                 if (ANTLR_LANGUAGES.contains(lang))        yield CSHARP_CAPS; // cpp etc → PARTIAL
diff --git a/src/main/java/io/github/randomcodespace/iq/mcp/McpTools.java b/src/main/java/io/github/randomcodespace/iq/mcp/McpTools.java
index ad40fefe..1d2fc22d 100644
--- a/src/main/java/io/github/randomcodespace/iq/mcp/McpTools.java
+++ b/src/main/java/io/github/randomcodespace/iq/mcp/McpTools.java
@@ -29,7 +29,6 @@
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
 
 /**
  * MCP tool definitions using Spring AI annotations.
@@ -39,6 +38,8 @@
 @Profile("serving")
 @org.springframework.boot.autoconfigure.condition.ConditionalOnProperty(name = "codeiq.neo4j.enabled", havingValue = "true", matchIfMissing = true)
 public class McpTools {
+    private static final String PROP_ERROR = "error";
+
 
     private final QueryService queryService;
     private final CodeIqConfig config;
@@ -93,7 +94,7 @@ public String getStats() {
         try {
             return toJson(queryService.getStats());
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -103,7 +104,7 @@ public String getDetailedStats(
         try {
             return toJson(queryService.getDetailedStats(category != null ? category : "all"));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -114,7 +115,7 @@ public String queryNodes(
         try {
             return toJson(queryService.listNodes(kind, limit != null ? limit : 50, 0));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -125,7 +126,7 @@ public String queryEdges(
         try {
             return toJson(queryService.listEdges(kind, limit != null ? limit : 50, 0));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -136,7 +137,7 @@ public String getNodeNeighbors(
         try {
             return toJson(queryService.getNeighbors(nodeId, direction != null ? direction : "both"));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -147,7 +148,7 @@ public String getEgoGraph(
         try {
             return toJson(queryService.egoGraph(center, radius != null ? radius : 2));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -157,7 +158,7 @@ public String findCycles(
         try {
             return toJson(queryService.findCycles(limit != null ? limit : 100));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -168,11 +169,11 @@ public String findShortestPath(
         try {
             Map<String, Object> result = queryService.shortestPath(source, target);
             if (result == null) {
-                return toJson(Map.of("error", "No path found between " + source + " and " + target));
+                return toJson(Map.of(PROP_ERROR, "No path found between " + source + " and " + target));
             }
             return toJson(result);
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -182,7 +183,7 @@ public String findConsumers(
         try {
             return toJson(queryService.consumersOf(targetId));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -192,7 +193,7 @@ public String findProducers(
         try {
             return toJson(queryService.producersOf(targetId));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -202,7 +203,7 @@ public String findCallers(
         try {
             return toJson(queryService.callersOf(targetId));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -212,7 +213,7 @@ public String findDependencies(
         try {
             return toJson(queryService.dependenciesOf(moduleId));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -222,7 +223,7 @@ public String findDependents(
         try {
             return toJson(queryService.dependentsOf(moduleId));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -234,7 +235,7 @@ public String findDeadCode(
             int safeLimit = limit != null ? Math.min(limit, 1000) : 100;
             return toJson(queryService.findDeadCode(kind, safeLimit));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -247,14 +248,14 @@ public String generateFlow(
         try {
             FlowEngine engine = resolveFlowEngine();
             if (engine == null) {
-                return toJson(Map.of("error", "No analysis data available. Run 'code-iq analyze' first."));
+                return toJson(Map.of(PROP_ERROR, "No analysis data available. Run 'code-iq analyze' first."));
             }
             FlowDiagram diagram = engine.generate(viewName);
             String rendered = engine.render(diagram, fmt);
             return rendered;
         } catch (IllegalArgumentException e) {
             Map<String, Object> error = new LinkedHashMap<>();
-            error.put("error", e.getMessage());
+            error.put(PROP_ERROR, e.getMessage());
             return toJson(error);
         }
     }
@@ -275,7 +276,7 @@ public String runCypher(
         for (String pattern : BLOCKED_PATTERNS) {
             if (java.util.regex.Pattern.compile(pattern).matcher(upper).find()) {
                 String keyword = pattern.replace("\\b", "").replace("\\s+", " ");
-                return toJson(Map.of("error", "Read-only queries only. Mutation keyword found: " + keyword));
+                return toJson(Map.of(PROP_ERROR, "Read-only queries only. Mutation keyword found: " + keyword));
             }
         }
         try {
@@ -299,7 +300,7 @@ public String runCypher(
             response.put("count", rows.size());
             return toJson(response);
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -311,7 +312,7 @@ public String findComponentByFile(
         try {
             return toJson(queryService.findComponentByFile(filePath));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -322,7 +323,7 @@ public String traceImpact(
         try {
             return toJson(queryService.traceImpact(nodeId, depth != null ? depth : 3));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -332,7 +333,7 @@ public String findRelatedEndpoints(
         try {
             return toJson(queryService.findRelatedEndpoints(identifier));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -343,7 +344,7 @@ public String searchGraph(
         try {
             return toJson(queryService.searchGraph(query, limit != null ? limit : 20));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -363,7 +364,7 @@ public String getCapabilities(
             }
             return toJson(result);
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -377,7 +378,7 @@ public String readFile(
             Path resolved = root.resolve(filePath).normalize();
             // Path traversal protection
             if (!resolved.startsWith(root)) {
-                return toJson(Map.of("error", "Path traversal detected"));
+                return toJson(Map.of(PROP_ERROR, "Path traversal detected"));
             }
             String content = java.nio.file.Files.readString(resolved, java.nio.charset.StandardCharsets.UTF_8);
             if (startLine != null || endLine != null) {
@@ -396,7 +397,7 @@ public String readFile(
             }
             return content;
         } catch (Exception e) {
-            return toJson(Map.of("error", "Failed to read file: " + e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, "Failed to read file: " + e.getMessage()));
         }
     }
 
@@ -407,7 +408,7 @@ public String getTopology() {
         try {
             return toJson(queryService.getTopology());
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -418,7 +419,7 @@ public String serviceDetail(
             var data = getCachedData();
             return toJson(topologyService.serviceDetail(serviceName, data.nodes(), data.edges()));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -429,7 +430,7 @@ public String serviceDependencies(
             var data = getCachedData();
             return toJson(topologyService.serviceDependencies(serviceName, data.nodes(), data.edges()));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -440,7 +441,7 @@ public String serviceDependents(
             var data = getCachedData();
             return toJson(topologyService.serviceDependents(serviceName, data.nodes(), data.edges()));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -451,7 +452,7 @@ public String blastRadius(
             var data = getCachedData();
             return toJson(topologyService.blastRadius(nodeId, data.nodes(), data.edges()));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -463,7 +464,7 @@ public String findPath(
             var data = getCachedData();
             return toJson(topologyService.findPath(source, target, data.nodes(), data.edges()));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -473,7 +474,7 @@ public String findBottlenecks() {
             var data = getCachedData();
             return toJson(topologyService.findBottlenecks(data.nodes(), data.edges()));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -483,7 +484,7 @@ public String findCircularDeps() {
             var data = getCachedData();
             return toJson(topologyService.findCircularDeps(data.nodes(), data.edges()));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -493,7 +494,7 @@ public String findDeadServices() {
             var data = getCachedData();
             return toJson(topologyService.findDeadServices(data.nodes(), data.edges()));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -504,7 +505,7 @@ public String findNode(
             var data = getCachedData();
             return toJson(topologyService.findNode(query, data.nodes()));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
@@ -515,7 +516,7 @@ public String getEvidencePack(
             @McpToolParam(description = "Max lines per snippet (default: config value)", required = false) Integer maxSnippetLines,
             @McpToolParam(description = "Include cross-reference nodes (default: false)", required = false) Boolean includeReferences) {
         if (evidencePackAssembler == null) {
-            return toJson(Map.of("error", "Evidence pack service unavailable. Run 'enrich' first."));
+            return toJson(Map.of(PROP_ERROR, "Evidence pack service unavailable. Run 'enrich' first."));
         }
         try {
             EvidencePackRequest request = new EvidencePackRequest(
@@ -523,19 +524,19 @@ public String getEvidencePack(
                     Boolean.TRUE.equals(includeReferences));
             return toJson(evidencePackAssembler.assemble(request, artifactMetadata));
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
     @McpTool(name = "get_artifact_metadata", description = "Return artifact metadata: repo identity, commit SHA, build timestamp, extractor versions, capability matrix snapshot, and integrity hash.")
     public String getArtifactMetadata() {
         if (artifactMetadata == null) {
-            return toJson(Map.of("error", "Artifact metadata unavailable. Run 'enrich' first."));
+            return toJson(Map.of(PROP_ERROR, "Artifact metadata unavailable. Run 'enrich' first."));
         }
         try {
             return toJson(artifactMetadata);
         } catch (Exception e) {
-            return toJson(Map.of("error", e.getMessage()));
+            return toJson(Map.of(PROP_ERROR, e.getMessage()));
         }
     }
 
diff --git a/src/main/java/io/github/randomcodespace/iq/query/QueryService.java b/src/main/java/io/github/randomcodespace/iq/query/QueryService.java
index 154f4326..a8a9b11d 100644
--- a/src/main/java/io/github/randomcodespace/iq/query/QueryService.java
+++ b/src/main/java/io/github/randomcodespace/iq/query/QueryService.java
@@ -24,6 +24,22 @@
 @Service
 @ConditionalOnBean(GraphStore.class)
 public class QueryService {
+    private static final String PROP_CHILDREN = "children";
+    private static final String PROP_CNT = "cnt";
+    private static final String PROP_COUNT = "count";
+    private static final String PROP_DIRECTORY = "directory";
+    private static final String PROP_FILE = "file";
+    private static final String PROP_ID = "id";
+    private static final String PROP_KIND = "kind";
+    private static final String PROP_LAYER = "layer";
+    private static final String PROP_MODULE = "module";
+    private static final String PROP_NODECOUNT = "nodeCount";
+    private static final String PROP_NODES = "nodes";
+    private static final String PROP_PATH = "path";
+    private static final String PROP_SOURCE = "source";
+    private static final String PROP_TARGET = "target";
+    private static final String PROP_TOTAL = "total";
+
 
     private final GraphStore graphStore;
     private final CodeIqConfig config;
@@ -41,18 +57,18 @@ public Map<String, Object> getStats() {
         // Also include raw counts and breakdowns for backward compat
         Map<String, Long> nodesByKind = new LinkedHashMap<>();
         for (Map<String, Object> row : graphStore.countNodesByKind()) {
-            nodesByKind.put((String) row.get("kind"), ((Number) row.get("cnt")).longValue());
+            nodesByKind.put((String) row.get(PROP_KIND), ((Number) row.get(PROP_CNT)).longValue());
         }
         Map<String, Long> nodesByLayer = new LinkedHashMap<>();
         for (Map<String, Object> row : graphStore.countNodesByLayer()) {
-            nodesByLayer.put((String) row.get("layer"), ((Number) row.get("cnt")).longValue());
+            nodesByLayer.put((String) row.get(PROP_LAYER), ((Number) row.get(PROP_CNT)).longValue());
         }
 
         // Read from already-computed graph sub-map instead of re-querying
         @SuppressWarnings("unchecked")
         Map<String, Object> graphStats = (Map<String, Object>) result.get("graph");
         if (graphStats != null) {
-            result.put("node_count", graphStats.get("nodes"));
+            result.put("node_count", graphStats.get(PROP_NODES));
             result.put("edge_count", graphStats.get("edges"));
         } else {
             result.put("node_count", graphStore.count());
@@ -92,21 +108,21 @@ public Map<String, Object> listKinds() {
         List<Map<String, Object>> kinds = new ArrayList<>();
         rawCounts.stream()
                 .sorted((a, b) -> Long.compare(
-                        ((Number) b.get("cnt")).longValue(),
-                        ((Number) a.get("cnt")).longValue()))
+                        ((Number) b.get(PROP_CNT)).longValue(),
+                        ((Number) a.get(PROP_CNT)).longValue()))
                 .forEach(row -> {
                     Map<String, Object> m = new LinkedHashMap<>();
-                    m.put("kind", row.get("kind"));
-                    m.put("count", ((Number) row.get("cnt")).longValue());
+                    m.put(PROP_KIND, row.get(PROP_KIND));
+                    m.put(PROP_COUNT, ((Number) row.get(PROP_CNT)).longValue());
                     kinds.add(m);
                 });
         long totalNodes = rawCounts.stream()
-                .mapToLong(r -> ((Number) r.get("cnt")).longValue())
+                .mapToLong(r -> ((Number) r.get(PROP_CNT)).longValue())
                 .sum();
 
         Map<String, Object> result = new LinkedHashMap<>();
         result.put("kinds", kinds);
-        result.put("total", totalNodes);
+        result.put(PROP_TOTAL, totalNodes);
         return result;
     }
 
@@ -116,11 +132,11 @@ public Map<String, Object> nodesByKind(String kind, int limit, int offset) {
         long total = graphStore.countByKind(kind);
 
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("kind", kind);
-        result.put("total", total);
+        result.put(PROP_KIND, kind);
+        result.put(PROP_TOTAL, total);
         result.put("offset", offset);
         result.put("limit", limit);
-        result.put("nodes", nodes.stream().map(this::nodeToMap).toList());
+        result.put(PROP_NODES, nodes.stream().map(this::nodeToMap).toList());
         return result;
     }
 
@@ -133,8 +149,8 @@ public Map<String, Object> listNodes(String kind, int limit, int offset) {
         }
 
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("nodes", nodes.stream().map(this::nodeToMap).toList());
-        result.put("count", nodes.size());
+        result.put(PROP_NODES, nodes.stream().map(this::nodeToMap).toList());
+        result.put(PROP_COUNT, nodes.size());
         result.put("offset", offset);
         result.put("limit", limit);
         return result;
@@ -153,17 +169,17 @@ public Map<String, Object> listEdges(String kind, int limit, int offset) {
 
         List<Map<String, Object>> edges = rawEdges.stream().map(row -> {
             Map<String, Object> m = new LinkedHashMap<>();
-            m.put("id", row.get("id"));
-            m.put("kind", row.get("kind"));
-            m.put("source", row.get("sourceId"));
-            m.put("target", row.get("targetId"));
+            m.put(PROP_ID, row.get(PROP_ID));
+            m.put(PROP_KIND, row.get(PROP_KIND));
+            m.put(PROP_SOURCE, row.get("sourceId"));
+            m.put(PROP_TARGET, row.get("targetId"));
             return m;
         }).toList();
 
         Map<String, Object> result = new LinkedHashMap<>();
         result.put("edges", edges);
-        result.put("count", edges.size());
-        result.put("total", total);
+        result.put(PROP_COUNT, edges.size());
+        result.put(PROP_TOTAL, total);
         return result;
     }
 
@@ -196,7 +212,7 @@ public Map<String, Object> getNeighbors(String nodeId, String direction) {
         result.put("node_id", nodeId);
         result.put("direction", direction);
         result.put("neighbors", neighbors.stream().map(this::nodeToMap).toList());
-        result.put("count", neighbors.size());
+        result.put(PROP_COUNT, neighbors.size());
         return result;
     }
 
@@ -208,9 +224,9 @@ public Map<String, Object> shortestPath(String source, String target) {
             return null;
         }
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("source", source);
-        result.put("target", target);
-        result.put("path", path);
+        result.put(PROP_SOURCE, source);
+        result.put(PROP_TARGET, target);
+        result.put(PROP_PATH, path);
         result.put("length", path.size() - 1);
         return result;
     }
@@ -220,7 +236,7 @@ public Map<String, Object> findCycles(int limit) {
         List<List<String>> cycles = graphStore.findCycles(cappedLimit);
         Map<String, Object> result = new LinkedHashMap<>();
         result.put("cycles", cycles);
-        result.put("count", cycles.size());
+        result.put(PROP_COUNT, cycles.size());
         return result;
     }
 
@@ -230,10 +246,10 @@ public Map<String, Object> traceImpact(String nodeId, int depth) {
         List<CodeNode> impacted = graphStore.traceImpact(nodeId, cappedDepth);
 
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("source", nodeId);
+        result.put(PROP_SOURCE, nodeId);
         result.put("depth", cappedDepth);
         result.put("impacted", impacted.stream().map(this::nodeToMap).toList());
-        result.put("count", impacted.size());
+        result.put(PROP_COUNT, impacted.size());
         return result;
     }
 
@@ -251,8 +267,8 @@ public Map<String, Object> egoGraph(String center, int radius) {
         Map<String, Object> result = new LinkedHashMap<>();
         result.put("center", center);
         result.put("radius", cappedRadius);
-        result.put("nodes", nodes.stream().map(this::nodeToMap).toList());
-        result.put("count", nodes.size());
+        result.put(PROP_NODES, nodes.stream().map(this::nodeToMap).toList());
+        result.put(PROP_COUNT, nodes.size());
         return result;
     }
 
@@ -262,18 +278,18 @@ public Map<String, Object> egoGraph(String center, int radius) {
     public Map<String, Object> consumersOf(String targetId) {
         List<CodeNode> consumers = graphStore.findConsumers(targetId);
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("target", targetId);
+        result.put(PROP_TARGET, targetId);
         result.put("consumers", consumers.stream().map(this::nodeToMap).toList());
-        result.put("count", consumers.size());
+        result.put(PROP_COUNT, consumers.size());
         return result;
     }
 
     public Map<String, Object> producersOf(String targetId) {
         List<CodeNode> producers = graphStore.findProducers(targetId);
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("target", targetId);
+        result.put(PROP_TARGET, targetId);
         result.put("producers", producers.stream().map(this::nodeToMap).toList());
-        result.put("count", producers.size());
+        result.put(PROP_COUNT, producers.size());
         return result;
     }
 
@@ -281,27 +297,27 @@ public Map<String, Object> producersOf(String targetId) {
     public Map<String, Object> callersOf(String targetId) {
         List<CodeNode> callers = graphStore.findCallers(targetId);
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("target", targetId);
+        result.put(PROP_TARGET, targetId);
         result.put("callers", callers.stream().map(this::nodeToMap).toList());
-        result.put("count", callers.size());
+        result.put(PROP_COUNT, callers.size());
         return result;
     }
 
     public Map<String, Object> dependenciesOf(String moduleId) {
         List<CodeNode> deps = graphStore.findDependencies(moduleId);
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("module", moduleId);
+        result.put(PROP_MODULE, moduleId);
         result.put("dependencies", deps.stream().map(this::nodeToMap).toList());
-        result.put("count", deps.size());
+        result.put(PROP_COUNT, deps.size());
         return result;
     }
 
     public Map<String, Object> dependentsOf(String moduleId) {
         List<CodeNode> deps = graphStore.findDependents(moduleId);
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("module", moduleId);
+        result.put(PROP_MODULE, moduleId);
         result.put("dependents", deps.stream().map(this::nodeToMap).toList());
-        result.put("count", deps.size());
+        result.put(PROP_COUNT, deps.size());
         return result;
     }
 
@@ -311,13 +327,13 @@ public Map<String, Object> dependentsOf(String moduleId) {
     public Map<String, Object> findComponentByFile(String filePath) {
         List<CodeNode> nodes = graphStore.findByFilePath(filePath);
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("file", filePath);
-        result.put("nodes", nodes.stream().map(this::nodeToMap).toList());
-        result.put("count", nodes.size());
+        result.put(PROP_FILE, filePath);
+        result.put(PROP_NODES, nodes.stream().map(this::nodeToMap).toList());
+        result.put(PROP_COUNT, nodes.size());
 
         if (!nodes.isEmpty()) {
             CodeNode first = nodes.getFirst();
-            result.put("module", first.getModule());
+            result.put(PROP_MODULE, first.getModule());
             result.put("layer", first.getLayer());
         }
         return result;
@@ -343,17 +359,17 @@ public Map<String, Object> getFileTree(Integer maxDepth) {
         GraphStore.FilePathResult filePathResult = graphStore.getFilePathsWithCounts(config.getMaxFiles());
         List<Map<String, Object>> rows = filePathResult.rows();
 
-        TreeNode root = new TreeNode("", "directory");
+        TreeNode root = new TreeNode("", PROP_DIRECTORY);
         for (Map<String, Object> row : rows) {
             String filePath = (String) row.get("filePath");
-            long count = ((Number) row.get("nodeCount")).longValue();
+            long count = ((Number) row.get(PROP_NODECOUNT)).longValue();
             String[] parts = filePath.split("/", -1);
             TreeNode current = root;
             for (int i = 0; i < parts.length; i++) {
                 String part = parts[i];
                 if (part.isEmpty()) continue;
                 boolean isFile = (i == parts.length - 1);
-                String type = isFile ? "file" : "directory";
+                String type = isFile ? PROP_FILE : PROP_DIRECTORY;
                 TreeNode child = current.children.computeIfAbsent(part, k -> new TreeNode(k, type));
                 if (isFile) {
                     child.nodeCount += count;
@@ -386,13 +402,13 @@ private List<Map<String, Object>> buildTreeOutput(TreeNode node, Integer maxDept
             String childPath = parentPath.isEmpty() ? child.name : parentPath + "/" + child.name;
             Map<String, Object> m = new LinkedHashMap<>();
             m.put("name", child.name);
-            m.put("path", childPath);
-            m.put("type", "directory");
-            m.put("nodeCount", aggregateCount(child));
+            m.put(PROP_PATH, childPath);
+            m.put("type", PROP_DIRECTORY);
+            m.put(PROP_NODECOUNT, aggregateCount(child));
             if (maxDepth == null || currentDepth < maxDepth) {
-                m.put("children", buildTreeOutput(child, maxDepth, currentDepth + 1, childPath));
+                m.put(PROP_CHILDREN, buildTreeOutput(child, maxDepth, currentDepth + 1, childPath));
             } else {
-                m.put("children", List.of());
+                m.put(PROP_CHILDREN, List.of());
             }
             output.add(m);
         }
@@ -400,10 +416,10 @@ private List<Map<String, Object>> buildTreeOutput(TreeNode node, Integer maxDept
             String childPath = parentPath.isEmpty() ? child.name : parentPath + "/" + child.name;
             Map<String, Object> m = new LinkedHashMap<>();
             m.put("name", child.name);
-            m.put("path", childPath);
-            m.put("type", "file");
-            m.put("nodeCount", child.nodeCount);
-            m.put("children", List.of());
+            m.put(PROP_PATH, childPath);
+            m.put("type", PROP_FILE);
+            m.put(PROP_NODECOUNT, child.nodeCount);
+            m.put(PROP_CHILDREN, List.of());
             output.add(m);
         }
         return output;
@@ -468,7 +484,7 @@ public Map<String, Object> findRelatedEndpoints(String identifier) {
         Map<String, Object> result = new LinkedHashMap<>();
         result.put("identifier", identifier);
         result.put("endpoints", endpoints);
-        result.put("count", endpoints.size());
+        result.put(PROP_COUNT, endpoints.size());
         result.put("searched_nodes", matches.size());
         return result;
     }
@@ -533,17 +549,17 @@ public Map<String, Object> findDeadCode(String kind, int limit) {
         List<Map<String, Object>> deadCode = deadNodes.stream()
                 .map(n -> {
                     Map<String, Object> m = new LinkedHashMap<>();
-                    m.put("id", n.getId());
-                    m.put("kind", n.getKind().getValue());
+                    m.put(PROP_ID, n.getId());
+                    m.put(PROP_KIND, n.getKind().getValue());
                     m.put("label", n.getLabel());
-                    m.put("file", n.getFilePath());
+                    m.put(PROP_FILE, n.getFilePath());
                     return m;
                 })
                 .toList();
 
         Map<String, Object> result = new LinkedHashMap<>();
         result.put("dead_code", deadCode);
-        result.put("count", deadCode.size());
+        result.put(PROP_COUNT, deadCode.size());
         return result;
     }
 
@@ -551,15 +567,15 @@ public Map<String, Object> findDeadCode(String kind, int limit) {
 
     Map<String, Object> nodeToMap(CodeNode node) {
         Map<String, Object> m = new LinkedHashMap<>();
-        m.put("id", node.getId());
-        m.put("kind", node.getKind().getValue());
+        m.put(PROP_ID, node.getId());
+        m.put(PROP_KIND, node.getKind().getValue());
         m.put("label", node.getLabel());
         if (node.getFqn() != null) m.put("fqn", node.getFqn());
-        if (node.getModule() != null) m.put("module", node.getModule());
+        if (node.getModule() != null) m.put(PROP_MODULE, node.getModule());
         if (node.getFilePath() != null) m.put("file_path", node.getFilePath());
         if (node.getLineStart() != null) m.put("line_start", node.getLineStart());
         if (node.getLineEnd() != null) m.put("line_end", node.getLineEnd());
-        if (node.getLayer() != null) m.put("layer", node.getLayer());
+        if (node.getLayer() != null) m.put(PROP_LAYER, node.getLayer());
         if (node.getAnnotations() != null && !node.getAnnotations().isEmpty()) {
             m.put("annotations", node.getAnnotations());
         }
@@ -571,11 +587,11 @@ Map<String, Object> nodeToMap(CodeNode node) {
 
     private Map<String, Object> edgeToMap(CodeEdge edge) {
         Map<String, Object> m = new LinkedHashMap<>();
-        m.put("id", edge.getId());
-        m.put("kind", edge.getKind().getValue());
-        m.put("source", edge.getSourceId());
+        m.put(PROP_ID, edge.getId());
+        m.put(PROP_KIND, edge.getKind().getValue());
+        m.put(PROP_SOURCE, edge.getSourceId());
         if (edge.getTarget() != null) {
-            m.put("target", edge.getTarget().getId());
+            m.put(PROP_TARGET, edge.getTarget().getId());
             m.put("target_label", edge.getTarget().getLabel());
             m.put("target_kind", edge.getTarget().getKind().getValue());
         }
diff --git a/src/main/java/io/github/randomcodespace/iq/query/TopologyService.java b/src/main/java/io/github/randomcodespace/iq/query/TopologyService.java
index b784c2d0..10ffca74 100644
--- a/src/main/java/io/github/randomcodespace/iq/query/TopologyService.java
+++ b/src/main/java/io/github/randomcodespace/iq/query/TopologyService.java
@@ -29,6 +29,15 @@
  */
 @Service
 public class TopologyService {
+    private static final String PROP_CONNECTIONS = "connections";
+    private static final String PROP_ENDPOINT_COUNT = "endpoint_count";
+    private static final String PROP_ENTITY_COUNT = "entity_count";
+    private static final String PROP_SERVICE = "service";
+    private static final String PROP_SOURCE = "source";
+    private static final String PROP_TARGET = "target";
+    private static final String PROP_TOTAL_CONNECTIONS = "total_connections";
+    private static final String PROP_TYPE = "type";
+
 
     /** Edge kinds that represent runtime service-to-service connections. */
     private static final Set<EdgeKind> RUNTIME_EDGES = EnumSet.of(
@@ -59,15 +68,15 @@ public Map<String, Object> getTopology(List<CodeNode> nodes, List<CodeEdge> edge
             Map<String, Object> svcMap = new LinkedHashMap<>();
             svcMap.put("name", svc.getLabel());
             svcMap.put("build_tool", svc.getProperties().getOrDefault("build_tool", "unknown"));
-            svcMap.put("endpoint_count", svc.getProperties().getOrDefault("endpoint_count", 0));
-            svcMap.put("entity_count", svc.getProperties().getOrDefault("entity_count", 0));
+            svcMap.put(PROP_ENDPOINT_COUNT, svc.getProperties().getOrDefault(PROP_ENDPOINT_COUNT, 0));
+            svcMap.put(PROP_ENTITY_COUNT, svc.getProperties().getOrDefault(PROP_ENTITY_COUNT, 0));
 
             String name = svc.getLabel();
             long outCount = connections.stream()
-                    .filter(c -> name.equals(c.get("source")))
+                    .filter(c -> name.equals(c.get(PROP_SOURCE)))
                     .count();
             long inCount = connections.stream()
-                    .filter(c -> name.equals(c.get("target")))
+                    .filter(c -> name.equals(c.get(PROP_TARGET)))
                     .count();
             svcMap.put("connections_out", outCount);
             svcMap.put("connections_in", inCount);
@@ -76,7 +85,7 @@ public Map<String, Object> getTopology(List<CodeNode> nodes, List<CodeEdge> edge
 
         Map<String, Object> result = new LinkedHashMap<>();
         result.put("services", services);
-        result.put("connections", connections);
+        result.put(PROP_CONNECTIONS, connections);
         result.put("service_count", services.size());
         result.put("connection_count", connections.size());
         return result;
@@ -119,8 +128,8 @@ public Map<String, Object> serviceDetail(String serviceName, List<CodeNode> node
         // Connections involving this service
         Map<String, String> nodeToService = buildNodeToServiceMap(nodes);
         List<Map<String, Object>> connections = findCrossServiceConnections(edges, nodeToService);
-        result.put("connections", connections.stream()
-                .filter(c -> serviceName.equals(c.get("source")) || serviceName.equals(c.get("target")))
+        result.put(PROP_CONNECTIONS, connections.stream()
+                .filter(c -> serviceName.equals(c.get(PROP_SOURCE)) || serviceName.equals(c.get(PROP_TARGET)))
                 .toList());
 
         result.put("files", childNodes.stream()
@@ -141,17 +150,17 @@ public Map<String, Object> serviceDependencies(String serviceName, List<CodeNode
         List<Map<String, Object>> connections = findCrossServiceConnections(edges, nodeToService);
 
         List<Map<String, Object>> deps = connections.stream()
-                .filter(c -> serviceName.equals(c.get("source")))
+                .filter(c -> serviceName.equals(c.get(PROP_SOURCE)))
                 .toList();
 
         Set<String> depServices = deps.stream()
-                .map(c -> (String) c.get("target"))
+                .map(c -> (String) c.get(PROP_TARGET))
                 .collect(Collectors.toCollection(LinkedHashSet::new));
 
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("service", serviceName);
+        result.put(PROP_SERVICE, serviceName);
         result.put("depends_on", depServices);
-        result.put("connections", deps);
+        result.put(PROP_CONNECTIONS, deps);
         result.put("count", depServices.size());
         return result;
     }
@@ -164,17 +173,17 @@ public Map<String, Object> serviceDependents(String serviceName, List<CodeNode>
         List<Map<String, Object>> connections = findCrossServiceConnections(edges, nodeToService);
 
         List<Map<String, Object>> deps = connections.stream()
-                .filter(c -> serviceName.equals(c.get("target")))
+                .filter(c -> serviceName.equals(c.get(PROP_TARGET)))
                 .toList();
 
         Set<String> dependentServices = deps.stream()
-                .map(c -> (String) c.get("source"))
+                .map(c -> (String) c.get(PROP_SOURCE))
                 .collect(Collectors.toCollection(LinkedHashSet::new));
 
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("service", serviceName);
+        result.put(PROP_SERVICE, serviceName);
         result.put("depended_by", dependentServices);
-        result.put("connections", deps);
+        result.put(PROP_CONNECTIONS, deps);
         result.put("count", dependentServices.size());
         return result;
     }
@@ -238,7 +247,7 @@ public Map<String, Object> blastRadius(String nodeId, List<CodeNode> nodes, List
         }
 
         Map<String, Object> result = new LinkedHashMap<>();
-        result.put("source", nodeId);
+        result.put(PROP_SOURCE, nodeId);
         result.put("affected_services", affectedServices);
         result.put("affected_nodes", affectedNodes);
         result.put("affected_service_count", affectedServices.size());
@@ -257,8 +266,8 @@ public List<Map<String, Object>> findPath(String source, String target,
         // Build service-level adjacency
         Map<String, Map<String, Map<String, Object>>> adj = new HashMap<>();
         for (Map<String, Object> conn : connections) {
-            String src = (String) conn.get("source");
-            String tgt = (String) conn.get("target");
+            String src = (String) conn.get(PROP_SOURCE);
+            String tgt = (String) conn.get(PROP_TARGET);
             adj.computeIfAbsent(src, k -> new HashMap<>()).putIfAbsent(tgt, conn);
         }
 
@@ -280,7 +289,7 @@ public List<Map<String, Object>> findPath(String source, String target,
                     Map<String, Object> step = new LinkedHashMap<>();
                     step.put("from", path.get(i));
                     step.put("to", path.get(i + 1));
-                    step.put("type", hop.getOrDefault("type", "unknown"));
+                    step.put(PROP_TYPE, hop.getOrDefault(PROP_TYPE, "unknown"));
                     result.add(step);
                 }
                 return result;
@@ -309,8 +318,8 @@ public List<Map<String, Object>> findBottlenecks(List<CodeNode> nodes, List<Code
         Map<String, Integer> outDegree = new HashMap<>();
 
         for (Map<String, Object> conn : connections) {
-            String src = (String) conn.get("source");
-            String tgt = (String) conn.get("target");
+            String src = (String) conn.get(PROP_SOURCE);
+            String tgt = (String) conn.get(PROP_TARGET);
             outDegree.merge(src, 1, Integer::sum);
             inDegree.merge(tgt, 1, Integer::sum);
         }
@@ -325,18 +334,18 @@ public List<Map<String, Object>> findBottlenecks(List<CodeNode> nodes, List<Code
             int total = in + out;
             if (total > 0) {
                 Map<String, Object> entry = new LinkedHashMap<>();
-                entry.put("service", name);
+                entry.put(PROP_SERVICE, name);
                 entry.put("connections_in", in);
                 entry.put("connections_out", out);
-                entry.put("total_connections", total);
+                entry.put(PROP_TOTAL_CONNECTIONS, total);
                 result.add(entry);
             }
         }
 
         // Sort by total connections descending
         result.sort((a, b) -> Integer.compare(
-                (int) b.get("total_connections"),
-                (int) a.get("total_connections")));
+                (int) b.get(PROP_TOTAL_CONNECTIONS),
+                (int) a.get(PROP_TOTAL_CONNECTIONS)));
         return result;
     }
 
@@ -350,8 +359,8 @@ public List<List<String>> findCircularDeps(List<CodeNode> nodes, List<CodeEdge>
         // Build adjacency
         Map<String, Set<String>> adj = new HashMap<>();
         for (Map<String, Object> conn : connections) {
-            String src = (String) conn.get("source");
-            String tgt = (String) conn.get("target");
+            String src = (String) conn.get(PROP_SOURCE);
+            String tgt = (String) conn.get(PROP_TARGET);
             adj.computeIfAbsent(src, k -> new LinkedHashSet<>()).add(tgt);
         }
 
@@ -359,7 +368,7 @@ public List<List<String>> findCircularDeps(List<CodeNode> nodes, List<CodeEdge>
         List<List<String>> cycles = new ArrayList<>();
         Set<String> allServices = new LinkedHashSet<>(adj.keySet());
         for (Map<String, Object> conn : connections) {
-            allServices.add((String) conn.get("target"));
+            allServices.add((String) conn.get(PROP_TARGET));
         }
 
         Set<String> globalVisited = new HashSet<>();
@@ -423,16 +432,16 @@ public List<Map<String, Object>> findDeadServices(List<CodeNode> nodes, List<Cod
         Map<String, CodeNode> serviceNodes = findServiceNodes(nodes);
 
         Set<String> hasIncoming = connections.stream()
-                .map(c -> (String) c.get("target"))
+                .map(c -> (String) c.get(PROP_TARGET))
                 .collect(Collectors.toSet());
 
         List<Map<String, Object>> result = new ArrayList<>();
         for (CodeNode svc : sortedValues(serviceNodes)) {
             if (!hasIncoming.contains(svc.getLabel())) {
                 Map<String, Object> entry = new LinkedHashMap<>();
-                entry.put("service", svc.getLabel());
-                entry.put("endpoint_count", svc.getProperties().getOrDefault("endpoint_count", 0));
-                entry.put("entity_count", svc.getProperties().getOrDefault("entity_count", 0));
+                entry.put(PROP_SERVICE, svc.getLabel());
+                entry.put(PROP_ENDPOINT_COUNT, svc.getProperties().getOrDefault(PROP_ENDPOINT_COUNT, 0));
+                entry.put(PROP_ENTITY_COUNT, svc.getProperties().getOrDefault(PROP_ENTITY_COUNT, 0));
                 result.add(entry);
             }
         }
@@ -485,7 +494,7 @@ private Map<String, CodeNode> findServiceNodes(List<CodeNode> nodes) {
     private Map<String, String> buildNodeToServiceMap(List<CodeNode> nodes) {
         Map<String, String> map = new HashMap<>();
         for (CodeNode node : nodes) {
-            Object svc = node.getProperties().get("service");
+            Object svc = node.getProperties().get(PROP_SERVICE);
             if (svc instanceof String s && !s.isBlank()) {
                 map.put(node.getId(), s);
             }
@@ -517,9 +526,9 @@ private List<Map<String, Object>> findCrossServiceConnections(
                 String key = sourceSvc + "->" + targetSvc + ":" + edge.getKind().getValue();
                 if (seen.add(key)) {
                     Map<String, Object> conn = new LinkedHashMap<>();
-                    conn.put("source", sourceSvc);
-                    conn.put("target", targetSvc);
-                    conn.put("type", edge.getKind().getValue());
+                    conn.put(PROP_SOURCE, sourceSvc);
+                    conn.put(PROP_TARGET, targetSvc);
+                    conn.put(PROP_TYPE, edge.getKind().getValue());
                     connections.add(conn);
                 }
             }
@@ -534,8 +543,8 @@ private Map<String, Object> nodeToCompact(CodeNode node) {
         m.put("label", node.getLabel());
         if (node.getFilePath() != null) m.put("file_path", node.getFilePath());
         if (node.getLayer() != null) m.put("layer", node.getLayer());
-        Object svc = node.getProperties().get("service");
-        if (svc != null) m.put("service", svc);
+        Object svc = node.getProperties().get(PROP_SERVICE);
+        if (svc != null) m.put(PROP_SERVICE, svc);
         return m;
     }
 
@@ -553,7 +562,7 @@ private static List<String> sorted(Set<String> set) {
     }
 
     private static String serviceOf(CodeNode node) {
-        Object svc = node.getProperties().get("service");
+        Object svc = node.getProperties().get(PROP_SERVICE);
         return svc instanceof String s ? s : null;
     }
 }
diff --git a/src/test/java/io/github/randomcodespace/iq/analyzer/StructuredParserTest.java b/src/test/java/io/github/randomcodespace/iq/analyzer/StructuredParserTest.java
index 4a12a687..795c6b2e 100644
--- a/src/test/java/io/github/randomcodespace/iq/analyzer/StructuredParserTest.java
+++ b/src/test/java/io/github/randomcodespace/iq/analyzer/StructuredParserTest.java
@@ -69,7 +69,7 @@ void parsesNestedYaml() {
     @Test
     void invalidYamlReturnsNull() {
         // SnakeYAML is quite lenient, but truly broken input should not crash
-        Object result = parser.parse("yaml", ":::\n---\n{{invalid", "bad.yaml");
+        parser.parse("yaml", ":::\n---\n{{invalid", "bad.yaml");
         // May return null or a partial parse — just don't throw
         // (SnakeYAML treats many things as strings, so this might not be null)
     }