diff --git a/lib/mimicry/mock_api.ex b/lib/mimicry/mock_api.ex
index ff50280..2ee083b 100644
--- a/lib/mimicry/mock_api.ex
+++ b/lib/mimicry/mock_api.ex
@@ -21,8 +21,6 @@ defmodule Mimicry.MockAPI do
       conn
       |> get_req_header("x-mimicry-expect-status")
       |> List.first()
-      # TODO: For JSON, all keys are strings, always
-      |> ensure_numerical()
       |> fallback("default")
 
     expected_example =
@@ -94,13 +92,4 @@ defmodule Mimicry.MockAPI do
       body: value
     }
   end
-
-  defp ensure_numerical(nil), do: nil
-
-  defp ensure_numerical(maybe_number) do
-    case Integer.parse(maybe_number) do
-      :error -> nil
-      {number, _} -> number
-    end
-  end
 end
diff --git a/lib/mimicry/open_api/parser.ex b/lib/mimicry/open_api/parser.ex
index 454225d..7b664ea 100644
--- a/lib/mimicry/open_api/parser.ex
+++ b/lib/mimicry/open_api/parser.ex
@@ -18,9 +18,11 @@ defmodule Mimicry.OpenAPI.Parser do
   def json(str), do: parse(str, :json)
 
   @doc """
-  parses a given string depending on its extension
+  parses a given string based on the extension to a Mimicry.Specifaction
+
+  If you need a map instead of the specification, see parse_to_map/2
   """
-  @spec parse(String.t(), :yaml | :json) :: Specification.t()
+  @spec parse(term(), :yaml | :json) :: Specification.t()
   def parse(str, atom) do
     str
     |> decoder(atom).()
@@ -35,10 +37,28 @@ defmodule Mimicry.OpenAPI.Parser do
     end
   end
 
+  @doc """
+  parses a given string to a map
+  """
+  @spec parse_to_map(any(), :yaml | :json) :: :error | any()
+  def parse_to_map(str, atom) do
+    str
+    |> decoder(atom).()
+    |> case do
+      {:ok, decoded} ->
+        decoded
+
+      {:error, err} ->
+        Logger.warn("Could not decode #{atom |> to_string() |> String.upcase()} specification")
+        Logger.error(err)
+        :error
+    end
+  end
+
   @doc """
   builds a new Specification from inputs given
   """
-  @spec build_specification(map()) :: Specification.t()
+  @spec build_specification(any()) :: Specification.t()
   def build_specification(
         parsed = %{
           "info" => info,
@@ -65,6 +85,7 @@ defmodule Mimicry.OpenAPI.Parser do
       # NOTE: This cannot read multiple specifications in a YAML file as of yet
       :yaml -> &YamlElixir.read_from_string/1
       :json -> &Jason.decode/1
+      _ -> raise RuntimeError, "Unknown extension: #{atom}"
     end
   end
 end
diff --git a/lib/mimicry/open_api/response.ex b/lib/mimicry/open_api/response.ex
index 4ecbb2b..177b62a 100644
--- a/lib/mimicry/open_api/response.ex
+++ b/lib/mimicry/open_api/response.ex
@@ -2,5 +2,5 @@ defmodule Mimicry.OpenAPI.Response do
   @moduledoc """
   A struct to represent a potential response based on the `Mimicry.OpenAPI.Specification` powering the `MockServer`.
   """
-  defstruct [:content_type, :schema, :description, examples: %{}, status: 200]
+  defstruct [:content_type, :schema, :description, examples: %{}, status: "200"]
 end
diff --git a/lib/mimicry_api/controllers/proxy_controller.ex b/lib/mimicry_api/controllers/proxy_controller.ex
index 4df4d2c..8657277 100644
--- a/lib/mimicry_api/controllers/proxy_controller.ex
+++ b/lib/mimicry_api/controllers/proxy_controller.ex
@@ -41,7 +41,7 @@ defmodule MimicryApi.ProxyController do
     conn
     |> clean_default_headers()
     |> merge_resp_headers(headers)
-    |> put_status(status)
+    |> put_status(status |> as_integer())
     |> json(body)
   end
 
@@ -63,4 +63,11 @@ defmodule MimicryApi.ProxyController do
   end
 
   defp get_host(%Specification{}), do: nil
+
+  defp as_integer(val) do
+    case Integer.parse(val) do
+      {num, _} -> num
+      _ -> raise RuntimeError, message: "Cannot convert #{val} to proper response code"
+    end
+  end
 end
diff --git a/lib/mimicry_api/controllers/server_controller.ex b/lib/mimicry_api/controllers/server_controller.ex
index f130db2..d1e5174 100644
--- a/lib/mimicry_api/controllers/server_controller.ex
+++ b/lib/mimicry_api/controllers/server_controller.ex
@@ -3,33 +3,60 @@ defmodule MimicryApi.ServerController do
 
   alias Mimicry.{MockServer, MockServerList}
   alias Mimicry.OpenAPI.Parser, as: SpecParser
+  alias MimicryApi.Errors
 
   def index(conn, _params) do
     conn |> json(%{servers: MockServerList.list_servers()})
   end
 
-  def create(conn, %{"spec" => definition}) do
-    definition |> SpecParser.build_specification()
+  def create(conn, %{"json" => raw_definition}) do
+    spec = raw_definition |> SpecParser.parse_to_map(:json)
 
-    with spec <- definition |> SpecParser.build_specification(),
+    _create(conn, spec)
+  end
+
+  def create(conn, %{"yaml" => raw_definition}) do
+    spec = raw_definition |> SpecParser.parse_to_map(:yaml)
+    _create(conn, spec)
+  end
+
+  def create(conn, _) do
+    conn
+    |> put_status(:unprocessable_entity)
+    |> json(%{message: "Pass the raw spec either via 'yaml' or 'json' properties"})
+  end
+
+  defp _create(conn, definition) do
+    with :ok <- definition |> OpenAPIv3Validator.validate(),
+         spec <- definition |> SpecParser.build_specification(),
          {:ok, pid} <- MockServerList.create_server(spec),
          {:ok, %{id: id} = response} <- pid |> MockServer.get_details() do
       conn
       |> put_resp_header("x-mimicry-server-id", id |> to_string())
       |> json(response)
     else
+      {:error, errors} ->
+        conn
+        |> put_status(:bad_request)
+        |> json(%{
+          message: "Invalid specification",
+          errors: errors |> Errors.make_errors_from_openapi_validation()
+        })
+
       {:error, :invalid_spec} ->
         conn |> put_status(:bad_request) |> json(%{message: "Invalid specification!"})
 
       {:error, _} ->
         conn |> put_status(:bad_request) |> json(%{message: "Invalid JSON"})
     end
-  end
-
-  def create(conn, _) do
-    conn
-    |> put_status(:bad_request)
-    |> json(%{message: "Missing 'spec' property!"})
+  rescue
+    FunctionClauseError ->
+      conn
+      |> put_status(:unprocessable_entity)
+      |> json(%{
+        message:
+          "Could not parse specification. Please use strings for response codes instead of integers."
+      })
   end
 
   def spec(conn = %Plug.Conn{req_headers: headers}, _params) do
diff --git a/lib/mimicry_api/errors.ex b/lib/mimicry_api/errors.ex
new file mode 100644
index 0000000..b5e2753
--- /dev/null
+++ b/lib/mimicry_api/errors.ex
@@ -0,0 +1,8 @@
+defmodule MimicryApi.Errors do
+  @moduledoc """
+  Provides functions for transforming errors from libs into something usable to the API
+  """
+  def make_errors_from_openapi_validation(errors) do
+    errors |> Enum.map(fn {msg, path} -> %{path => msg} end)
+  end
+end
diff --git a/mix.exs b/mix.exs
index b6bf52b..afd08d9 100644
--- a/mix.exs
+++ b/mix.exs
@@ -41,6 +41,7 @@ defmodule Mimicry.MixProject do
       {:phoenix, "~> 1.5"},
       {:plug_cowboy, "~> 2.4"},
       {:yaml_elixir, "~> 2.6"},
+      {:openapiv3_validator, "~> 0.1.0"},
 
       # dev
       {:mix_test_watch, "~> 1.0", only: :dev, runtime: false},
diff --git a/mix.lock b/mix.lock
index 3884209..67ae9bb 100644
--- a/mix.lock
+++ b/mix.lock
@@ -10,6 +10,7 @@
   "earmark_parser": {:hex, :earmark_parser, "1.4.15", "b29e8e729f4aa4a00436580dcc2c9c5c51890613457c193cc8525c388ccb2f06", [:mix], [], "hexpm", "044523d6438ea19c1b8ec877ec221b008661d3c27e3b848f4c879f500421ca5c"},
   "erlex": {:hex, :erlex, "0.2.6", "c7987d15e899c7a2f34f5420d2a2ea0d659682c06ac607572df55a43753aa12e", [:mix], [], "hexpm", "2ed2e25711feb44d52b17d2780eabf998452f6efda104877a3881c2f8c0c0c75"},
   "ex_doc": {:hex, :ex_doc, "0.25.2", "4f1cae793c4d132e06674b282f1d9ea3bf409bcca027ddb2fe177c4eed6a253f", [:mix], [{:earmark_parser, "~> 1.4.0", [hex: :earmark_parser, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.14", [hex: :makeup_elixir, repo: "hexpm", optional: false]}, {:makeup_erlang, "~> 0.1", [hex: :makeup_erlang, repo: "hexpm", optional: false]}], "hexpm", "5b0c172e87ac27f14dfd152d52a145238ec71a95efbf29849550278c58a393d6"},
+  "ex_json_schema": {:hex, :ex_json_schema, "0.8.1", "d4cf78f318e7eea9ed173b4bb74b24a2d1601a7da5b5a857c07fe3d5da8f7fb6", [:mix], [], "hexpm", "4c870cfd422f6f5f4a6944cffde8eff029ba27b7f4783d94ed0f97ace27811d1"},
   "excoveralls": {:hex, :excoveralls, "0.14.2", "f9f5fd0004d7bbeaa28ea9606251bb643c313c3d60710bad1f5809c845b748f0", [:mix], [{:hackney, "~> 1.16", [hex: :hackney, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "ca6fd358621cb4d29311b29d4732c4d47dac70e622850979bc54ed9a3e50f3e1"},
   "file_system": {:hex, :file_system, "0.2.10", "fb082005a9cd1711c05b5248710f8826b02d7d1784e7c3451f9c1231d4fc162d", [:mix], [], "hexpm", "41195edbfb562a593726eda3b3e8b103a309b733ad25f3d642ba49696bf715dc"},
   "gettext": {:hex, :gettext, "0.18.2", "7df3ea191bb56c0309c00a783334b288d08a879f53a7014341284635850a6e55", [:mix], [], "hexpm", "f9f537b13d4fdd30f3039d33cb80144c3aa1f8d9698e47d7bcbcc8df93b1f5c5"},
@@ -25,6 +26,7 @@
   "mimerl": {:hex, :mimerl, "1.2.0", "67e2d3f571088d5cfd3e550c383094b47159f3eee8ffa08e64106cdf5e981be3", [:rebar3], [], "hexpm", "f278585650aa581986264638ebf698f8bb19df297f66ad91b18910dfc6e19323"},
   "mix_test_watch": {:hex, :mix_test_watch, "1.1.0", "330bb91c8ed271fe408c42d07e0773340a7938d8a0d281d57a14243eae9dc8c3", [:mix], [{:file_system, "~> 0.2.1 or ~> 0.3", [hex: :file_system, repo: "hexpm", optional: false]}], "hexpm", "52b6b1c476cbb70fd899ca5394506482f12e5f6b0d6acff9df95c7f1e0812ec3"},
   "nimble_parsec": {:hex, :nimble_parsec, "1.1.0", "3a6fca1550363552e54c216debb6a9e95bd8d32348938e13de5eda962c0d7f89", [:mix], [], "hexpm", "08eb32d66b706e913ff748f11694b17981c0b04a33ef470e33e11b3d3ac8f54b"},
+  "openapiv3_validator": {:hex, :openapiv3_validator, "0.1.0", "ebcfe821bb29ab6259612286aba72795264a9e5b68d7f8f02117fb0459cfda6d", [:mix], [{:ex_json_schema, "~> 0.8.1", [hex: :ex_json_schema, repo: "hexpm", optional: false]}], "hexpm", "ed3f63aad49415c93ad3cd980cb12942f18de19b2a247ad3e0ca83d4c0a327fb"},
   "parse_trans": {:hex, :parse_trans, "3.3.1", "16328ab840cc09919bd10dab29e431da3af9e9e7e7e6f0089dd5a2d2820011d8", [:rebar3], [], "hexpm", "07cd9577885f56362d414e8c4c4e6bdf10d43a8767abb92d24cbe8b24c54888b"},
   "phoenix": {:hex, :phoenix, "1.5.12", "75fddb14c720388eea93d33886166a690416a7ff8633fbd93f364355b6fe1166", [:mix], [{:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:phoenix_html, "~> 2.13 or ~> 3.0", [hex: :phoenix_html, repo: "hexpm", optional: true]}, {:phoenix_pubsub, "~> 2.0", [hex: :phoenix_pubsub, repo: "hexpm", optional: false]}, {:plug, "~> 1.10", [hex: :plug, repo: "hexpm", optional: false]}, {:plug_cowboy, "~> 1.0 or ~> 2.2", [hex: :plug_cowboy, repo: "hexpm", optional: true]}, {:plug_crypto, "~> 1.1.2 or ~> 1.2", [hex: :plug_crypto, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "8f0ae6734fcc18bbaa646c161e2febc46fb899eae43f82679b92530983324113"},
   "phoenix_pubsub": {:hex, :phoenix_pubsub, "2.0.0", "a1ae76717bb168cdeb10ec9d92d1480fec99e3080f011402c0a2d68d47395ffb", [:mix], [], "hexpm", "c52d948c4f261577b9c6fa804be91884b381a7f8f18450c5045975435350f771"},
diff --git a/test/fixtures/specs/simple-with-broken-integer.yaml b/test/fixtures/specs/simple-with-broken-integer.yaml
new file mode 100644
index 0000000..d56b239
--- /dev/null
+++ b/test/fixtures/specs/simple-with-broken-integer.yaml
@@ -0,0 +1,66 @@
+openapi: 3.0.3
+info:
+  title: 'Test YAML'
+  version: '1.0'
+  license:
+    name: MIT
+  description: 'A simple API'
+servers:
+  - url: https://simple-api.testing.com
+    description: production
+paths:
+  '/':
+    get:
+      responses:
+        default:
+          description: 'The default response for this endpoint'
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/SimpleMessage'
+              examples:
+                simple-reference:
+                  $ref: '#/components/examples/simple-message-example'
+                simple-embedded:
+                  summary: 'An embedded example'
+                  value:
+                    message: 'embedded message example'
+                simple-combined-example:
+                  $ref: '#/components/examples/simple-message-example'
+                  summary: 'simple example with overriden summary'
+        404: # <- this is the problem, while technically correct YAML, this will break the parser, since it need compat with JSON
+          description: The response for when something is not found
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/SimpleError'
+              examples:
+                simple-error:
+                  $ref: '#/components/examples/simple-error'
+
+components:
+  schemas:
+    SimpleMessage:
+      title: 'A simple message'
+      description: 'an example of a simple message'
+      type: object
+      properties:
+        message:
+          type: string
+    SimpleError:
+      title: 'A simple Error'
+      description: 'A simple error model'
+      type: object
+      properties:
+        code:
+          type: integer
+  examples:
+    simple-message-example:
+      summary: 'a simple message'
+      value:
+        message: 'foobar'
+    simple-error:
+      summary: 'a simple error'
+      value:
+        code: 42
+
diff --git a/test/fixtures/specs/simple.json b/test/fixtures/specs/simple.json
index 4f90b3a..32e0cba 100644
--- a/test/fixtures/specs/simple.json
+++ b/test/fixtures/specs/simple.json
@@ -1,7 +1,7 @@
 {
-  "openapi": "3.0.0",
+  "openapi": "3.0.3",
   "info": {
-    "title": "Test JSON",
+    "title": "Test YAML",
     "version": "1.0",
     "license": {
       "name": "MIT"
@@ -10,9 +10,94 @@
   },
   "servers": [
     {
-      "url": "https://simple-api.com",
+      "url": "https://simple-api.testing.com",
       "description": "production"
     }
   ],
-  "paths": []
-}
+  "paths": {
+    "/": {
+      "get": {
+        "responses": {
+          "404": {
+            "description": "The response for when something is not found",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/SimpleError"
+                },
+                "examples": {
+                  "simple-error": {
+                    "$ref": "#/components/examples/simple-error"
+                  }
+                }
+              }
+            }
+          },
+          "default": {
+            "description": "The default response for this endpoint",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/SimpleMessage"
+                },
+                "examples": {
+                  "simple-reference": {
+                    "$ref": "#/components/examples/simple-message-example"
+                  },
+                  "simple-embedded": {
+                    "summary": "An embedded example",
+                    "value": {
+                      "message": "embedded message example"
+                    }
+                  },
+                  "simple-combined-example": {
+                    "$ref": "#/components/examples/simple-message-example",
+                    "summary": "simple example with overriden summary"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  },
+  "components": {
+    "schemas": {
+      "SimpleMessage": {
+        "title": "A simple message",
+        "description": "an example of a simple message",
+        "type": "object",
+        "properties": {
+          "message": {
+            "type": "string"
+          }
+        }
+      },
+      "SimpleError": {
+        "title": "A simple Error",
+        "description": "A simple error model",
+        "type": "object",
+        "properties": {
+          "code": {
+            "type": "integer"
+          }
+        }
+      }
+    },
+    "examples": {
+      "simple-message-example": {
+        "summary": "a simple message",
+        "value": {
+          "message": "foobar"
+        }
+      },
+      "simple-error": {
+        "summary": "a simple error",
+        "value": {
+          "code": 42
+        }
+      }
+    }
+  }
+}
\ No newline at end of file
diff --git a/test/fixtures/specs/simple.yaml b/test/fixtures/specs/simple.yaml
index 02d1fb5..47da7be 100644
--- a/test/fixtures/specs/simple.yaml
+++ b/test/fixtures/specs/simple.yaml
@@ -28,7 +28,7 @@ paths:
                 simple-combined-example:
                   $ref: '#/components/examples/simple-message-example'
                   summary: 'simple example with overriden summary'
-        404:
+        '404':
           description: The response for when something is not found
           content:
             application/json:
diff --git a/test/mimicry/mock_api_test.exs b/test/mimicry/mock_api_test.exs
index 515fd70..9cdf885 100644
--- a/test/mimicry/mock_api_test.exs
+++ b/test/mimicry/mock_api_test.exs
@@ -7,7 +7,7 @@ defmodule Mimicry.MockAPITest do
   describe "respond/2" do
     @tag specification: "products-with-examples.yaml"
     test "will respond with a specific path", %{conn: conn, specification: spec} do
-      %{status: 200, body: _, headers: _} = conn |> get("/products") |> MockAPI.respond(spec)
+      %{status: "200", body: _, headers: _} = conn |> get("/products") |> MockAPI.respond(spec)
     end
 
     @tag specification: "products-with-examples.yaml"
@@ -15,7 +15,7 @@ defmodule Mimicry.MockAPITest do
       conn: conn,
       specification: spec
     } do
-      %{status: 200, body: product, headers: _} =
+      %{status: "200", body: product, headers: _} =
         conn |> get("/products/foobar") |> MockAPI.respond(spec)
 
       assert product == %{
diff --git a/test/mimicry_api/controllers/proxy_controller_test.exs b/test/mimicry_api/controllers/proxy_controller_test.exs
index 975583b..79e8817 100644
--- a/test/mimicry_api/controllers/proxy_controller_test.exs
+++ b/test/mimicry_api/controllers/proxy_controller_test.exs
@@ -69,6 +69,7 @@ defmodule MimicryApi.ProxyControllerTest do
     end
 
     @tag server: "simple.yaml"
+    @tag :focus
     test "GET / with an expected 404", %{conn: conn} do
       conn =
         conn
diff --git a/test/mimicry_api/controllers/server_controller_test.exs b/test/mimicry_api/controllers/server_controller_test.exs
index 6451003..fd7f8d3 100644
--- a/test/mimicry_api/controllers/server_controller_test.exs
+++ b/test/mimicry_api/controllers/server_controller_test.exs
@@ -2,6 +2,8 @@ defmodule MimicryApi.ServerControllerTest do
   use MimicryApi.ConnCase
   use Mimicry.MockServerCase
 
+  import Fixtures
+
   @tag server: "simple.yaml"
   test "GET /__mimicry/", %{conn: conn} do
     conn = conn |> get(Routes.server_path(conn, :index))
@@ -23,29 +25,87 @@ defmodule MimicryApi.ServerControllerTest do
   describe "POST /" do
     test "when the payload is not a spec", %{conn: conn} do
       conn = conn |> post(Routes.server_path(conn, :create, %{}))
-      assert %{"message" => message} = conn |> json_response(:bad_request)
-      assert message =~ "Missing"
+      assert %{"message" => message} = conn |> json_response(:unprocessable_entity)
+      assert message =~ "Pass the raw spec"
 
-      conn = conn |> post(Routes.server_path(conn, :create, %{"spec" => %{"foobar" => "foo"}}))
+      conn = conn |> post(Routes.server_path(conn, :create, %{yaml: "foobar"}))
 
       assert %{"message" => message} = conn |> json_response(:bad_request)
       assert message =~ "Invalid"
     end
 
-    test "when the payload is a spec", %{conn: conn} do
-      spec = %{
-        "openapi" => "3.0.0",
-        "info" => %{"title" => "myFreshNewApi", "version" => "1.0.0alpha"},
-        "servers" => [
-          %{"url" => "https://fresh-api.testing.com"}
-        ],
-        "paths" => [%{"/" => %{}}]
-      }
-
-      conn = conn |> post(Routes.server_path(conn, :create, %{"spec" => spec}))
+    test "when the payload is a YAML spec", %{conn: conn} do
+      spec = load_fixture("simple.yaml")
+
+      conn =
+        conn
+        |> post(
+          Routes.server_path(conn, :create, %{
+            "yaml" => spec
+          })
+        )
+
       assert _ = conn |> json_response(:ok)
       assert [_server_id] = conn |> get_resp_header("x-mimicry-server-id")
     end
+
+    test "when the payload is a JSON spec", %{conn: conn} do
+      spec = load_fixture("simple.json")
+
+      conn =
+        conn
+        |> post(
+          Routes.server_path(conn, :create, %{
+            "json" => spec
+          })
+        )
+
+      assert _ = conn |> json_response(:ok)
+      assert [_server_id] = conn |> get_resp_header("x-mimicry-server-id")
+    end
+
+    test "when the payload is an incomplete YAML spec", %{conn: conn} do
+      spec = "openapi: 3.0.0"
+
+      conn =
+        conn
+        |> post(Routes.server_path(conn, :create, %{yaml: spec}))
+
+      assert %{"message" => message, "errors" => errors} = conn |> json_response(:bad_request)
+      assert message =~ "Invalid"
+      assert errors |> length() > 0
+    end
+
+    test "when the payload is an incomplete JSON spec", %{conn: conn} do
+      spec = '''
+        { "openapi": "3.0.0" }
+      '''
+
+      conn =
+        conn
+        |> post(Routes.server_path(conn, :create, %{json: spec}))
+
+      assert %{"message" => message, "errors" => errors} = conn |> json_response(:bad_request)
+      assert message =~ "Invalid"
+      assert errors |> length() > 0
+    end
+
+    test "when the payload is YAML and contains integers as response codes", %{conn: conn} do
+      spec = load_fixture("simple-with-broken-integer.yaml")
+
+      conn =
+        conn
+        |> post(
+          Routes.server_path(conn, :create, %{
+            "yaml" => spec
+          })
+        )
+
+      assert %{"message" => message} = conn |> json_response(:unprocessable_entity)
+
+      assert message =~
+               "Could not parse specification"
+    end
   end
 
   describe "DELETE /:id" do
@@ -55,23 +115,16 @@ defmodule MimicryApi.ServerControllerTest do
     end
 
     test "when deleting an existing server", %{conn: conn} do
-      spec = %{
-        "openapi" => "3.0.0",
-        "info" => %{"title" => "mySuperDeletableApi", "version" => "1.0.0alpha"},
-        "paths" => [%{"/" => %{"get" => %{"responses" => %{"valid" => "spec"}}}}],
-        "servers" => [
-          %{"url" => "https://fresh-deletable-api.testing.com"}
-        ]
-      }
-
-      conn = conn |> post(Routes.server_path(conn, :create, %{"spec" => spec}))
+      spec = load_fixture("simple.yaml")
+
+      conn = conn |> post(Routes.server_path(conn, :create, %{"yaml" => spec}))
       assert _ = conn |> json_response(:ok)
       assert [server_id] = conn |> get_resp_header("x-mimicry-server-id")
 
       conn = conn |> delete(Routes.server_path(conn, :delete, server_id))
       assert response = conn |> json_response(:ok)
 
-      assert response == spec
+      assert response == YamlElixir.read_from_string!(spec)
     end
   end
 end
diff --git a/test/mimicry_api/errors_test.exs b/test/mimicry_api/errors_test.exs
new file mode 100644
index 0000000..8f7cbec
--- /dev/null
+++ b/test/mimicry_api/errors_test.exs
@@ -0,0 +1,16 @@
+defmodule MimicryApi.ErrorsTest do
+  use ExUnit.Case
+
+  alias MimicryApi.Errors
+
+  describe "make_errors_from_openapi_validation/2" do
+    test "will transform a list of tuples" do
+      tuples = [{"foobar", "#"}, {"barfoo", "#baz"}]
+
+      assert Errors.make_errors_from_openapi_validation(tuples) == [
+               %{"#" => "foobar"},
+               %{"#baz" => "barfoo"}
+             ]
+    end
+  end
+end
diff --git a/test/support/fixtures.ex b/test/support/fixtures.ex
new file mode 100644
index 0000000..f543bf1
--- /dev/null
+++ b/test/support/fixtures.ex
@@ -0,0 +1,12 @@
+defmodule Fixtures do
+  @moduledoc false
+
+  alias Mimicry.Utils.{SpecificationFileReader, SpecificationFolder}
+
+  def load_fixture(file) do
+    case SpecificationFolder.base_path() |> Path.join(file) |> SpecificationFileReader.read() do
+      {:ok, content, _extension} -> content
+      _ -> raise RuntimeError, message: "Fixture #{file} not found!"
+    end
+  end
+end