Rename StreamProxy helper to LiteRtLmBridge

README.md

@@ -13,8 +13,8 @@ Responsibilities:
 - Track upstream `google-ai-edge/LiteRT-LM` releases.
 - Fetch or build native LiteRT-LM libraries per platform.
 - Preserve upstream LiteRT-LM's C runtime ABI as the FFI boundary.
-- Embed the small StreamProxy callback-copy helper into runtime libraries used
-  by asynchronous FFI clients.
+- Embed the small LiteRtLmBridge callback helper into runtime libraries used by
+  asynchronous FFI clients.
 - Package web assets around official LiteRT-LM/LiteRT.js distribution paths.
 - Publish Apple Swift Package Manager XCFramework zip assets built from the
   same bridge runtimes as the native release payload.
@@ -53,11 +53,13 @@ GPU/NPU validation; web should use JavaScript interop instead of FFI.
 - `web/`: web package scaffold for JS/Wasm/WebGPU/WebNN integration.
 - `tools/fetch_upstream.py`: resolves and downloads upstream release assets.
 - `tools/build_upstream_runtime.py`: builds upstream LiteRT-LM C runtime
-  libraries from tagged source with Bazel/Bazelisk, embeds StreamProxy symbols
-  into source-built runtime libraries, and stages them for release.
+  libraries from tagged source with Bazel/Bazelisk through the repo-owned
+  `native/bridge` Bazel package, embeds LiteRtLmBridge symbols into
+  source-built runtime libraries without patching upstream source files, and
+  stages them for release.
 - `tools/package_ios_runtime.py`: extracts official upstream
   `CLiteRTLM.xcframework` slices and stages `LiteRtLm.framework` plus
-  `CLiteRTLM.framework`, with the wrapper embedding StreamProxy symbols and
+  `CLiteRTLM.framework`, with the wrapper embedding LiteRtLmBridge symbols and
   re-exporting `CLiteRTLM`.
 - `tools/package_apple_xcframeworks.py`: packages iOS framework wrappers, a
   macOS `LiteRtLm.framework` wrapper around the source-built runtime, and macOS
@@ -93,11 +95,11 @@ python3 tools/validate_artifacts.py
 - `Validate`: validates package metadata and checks Python/web tooling on
   pushes and pull requests.
 - `Native Build & Release`: manually packages a selected upstream LiteRT-LM tag.
-  It builds upstream C runtime libraries with embedded StreamProxy symbols for
+  It builds upstream C runtime libraries with embedded LiteRtLmBridge symbols for
   Android arm64/x64, macOS arm64/x64, Linux x64/arm64, and Windows x64, copies
   upstream `prebuilt/` companion libraries for Android, Apple, Linux, and
   Windows, converts official upstream `CLiteRTLM.xcframework` slices into iOS
-  framework runtime archives with an embedded-StreamProxy wrapper, packages
+  framework runtime archives with an embedded LiteRtLmBridge wrapper, packages
   Apple SPM XCFramework zips from the same runtime payloads, includes the
   official upstream release assets, then publishes a GitHub release with
   `manifest.json` and `SHA256SUMS`.
@@ -115,14 +117,18 @@ package hooks and Swift Package manifests. When moving to a new LiteRT-LM tag:
 2. Verify the release contains runtime archives, official upstream assets,
    Apple SPM XCFramework zips, `manifest.json`, and `SHA256SUMS`.
 3. Update downstream `llamadart` hook pins, SPM URLs, and SPM checksums
-   together so native-assets and SPM consumers use the same StreamProxy-enabled
+   together so native-assets and SPM consumers use the same bridge-enabled
    runtime build.
 
 The release workflow uses upstream's public C API (`c/engine.h`) as the
 production FFI boundary. Downstream loaders should bind directly to the runtime
-library for the selected platform. StreamProxy symbols are embedded into the
-same runtime library surface; no standalone StreamProxy runtime artifact is part
-of the release contract.
+library for the selected platform. Source-built native runtimes are assembled
+from a repo-owned Bazel package selected ahead of the upstream source tree with
+`--package_path`, so the workflow does not edit upstream LiteRT-LM files.
+LiteRtLmBridge symbols are embedded into the same runtime library surface; no
+standalone bridge runtime artifact is part of the release contract. The bridge
+currently exports the `stream_proxy_*` compatibility symbols used by
+asynchronous callback loaders.
 
 Apple SPM consumers should depend on the release's direct
 `litert-lm-native-apple-*-xcframework-<tag>.zip` assets. The `LiteRtLm`
@@ -142,4 +148,5 @@ architecture, runtime kind (`native` or `web`), and accelerator metadata, then
 verify checksums before bundling or loading the files.
 
 Upstream LiteRT-LM's native C ABI is the compatibility boundary. This repository
-does not add a second wrapper ABI unless a future upstream change requires it.
+does not add a second model wrapper ABI unless a future upstream change requires
+it; bridge helpers remain narrow FFI utilities around that runtime surface.

docs/current_upstream.md

@@ -1,19 +1,23 @@
 # Current Upstream Snapshot
 
-As of the first scaffold, the latest upstream release resolved by
+As of `2026-06-08`, the latest upstream release resolved by
 `tools/fetch_upstream.py --latest --metadata-only` is:
 
 - Repository: `google-ai-edge/LiteRT-LM`
-- Tag: `v0.12.0`
-- Published: `2026-05-18T20:53:57Z`
-- Release URL: `https://github.com/google-ai-edge/LiteRT-LM/releases/tag/v0.12.0`
-- Asset: `CLiteRTLM.xcframework.zip`
+- Tag: `v0.13.1`
+- Published: `2026-06-03T20:52:11Z`
+- Release URL: `https://github.com/google-ai-edge/LiteRT-LM/releases/tag/v0.13.1`
+- Assets:
+  - `CLiteRTLM.xcframework.zip`
+  - `CLiteRTLM_mac.xcframework.zip`
 
-Older release `v0.11.0` exposed standalone CLI assets for Android, iOS
-simulator, Linux x64, macOS arm64, and Windows x64. The native repo should not
-assume that upstream releases always publish the same asset matrix.
+Older releases have exposed different asset matrices. For example, `v0.11.0`
+included standalone CLI assets for Android, iOS simulator, Linux x64, macOS
+arm64, and Windows x64, while `v0.13.1` publishes Apple XCFramework archives.
+The native repo should not assume that upstream releases always publish the same
+asset matrix.
 
-The first production implementation should support both modes:
+Production packaging should support both modes:
 
 - consume official upstream artifacts when they exist and expose the required
   ABI/API surface

docs/platform_strategy.md

@@ -9,21 +9,24 @@ avoids publishing a second model wrapper ABI that does not add behavior.
 The release automation publishes these runtime artifact groups:
 
 - upstream LiteRT-LM C runtime libraries built from the tagged source archive,
-  with StreamProxy symbols embedded for downstream FFI streaming on source-built
-  platforms
+  with LiteRtLmBridge symbols embedded by the repo-owned `native/bridge` Bazel
+  package for downstream FFI streaming on source-built platforms
 - upstream `prebuilt/` companion libraries copied from the tagged source archive
 - official upstream release assets, including the iOS `CLiteRTLM.xcframework`
   archive when Google publishes it
 - iOS framework-style runtime wrappers derived from `CLiteRTLM.xcframework`,
-  with StreamProxy symbols embedded in `LiteRtLm.framework/LiteRtLm` and
+  with LiteRtLmBridge symbols embedded in `LiteRtLm.framework/LiteRtLm` and
   upstream symbols re-exported from `CLiteRTLM.framework/CLiteRTLM`
 - Apple Swift Package Manager XCFramework zips produced from the same iOS
   wrappers, macOS source-built runtime, and macOS companion dylibs used by the
   native-assets payloads
 
-The upstream C runtime is the production FFI target for downstream packages. If
-we later need a repo-owned compatibility layer, it should be introduced as a real
-wrapper over upstream LiteRT-LM rather than a scaffold library.
+The upstream C runtime is the production FFI target for downstream packages.
+LiteRtLmBridge is limited to narrow FFI helpers around that runtime surface. It
+currently exports the `stream_proxy_*` compatibility symbols used by downstream
+streaming callbacks. Source-built native runtimes use Bazel `--package_path` to
+build the repo-owned bridge package alongside upstream LiteRT-LM, without
+patching upstream source files.
 
 SPM artifacts are intentionally split by binary target. `LiteRtLm` carries the
 primary iOS runtime/wrapper and a macOS framework wrapper around the

native/bridge/BUILD.bazel

@@ -0,0 +1,42 @@
+package(default_visibility = ["//visibility:public"])
+
+cc_library(
+    name = "litert_lm_bridge",
+    srcs = ["litert_lm_bridge.c"],
+    alwayslink = True,
+    linkopts = select({
+        "@platforms//os:android": ["-ldl"],
+        "@platforms//os:linux": ["-ldl"],
+        "//conditions:default": [],
+    }),
+)
+
+cc_binary(
+    name = "libLiteRtLm.so",
+    linkshared = True,
+    deps = [
+        ":litert_lm_bridge",
+        "//c:engine",
+        "//schema/capabilities:capabilities_c",
+    ],
+)
+
+cc_binary(
+    name = "libLiteRtLm.dylib",
+    linkshared = True,
+    deps = [
+        ":litert_lm_bridge",
+        "//c:engine",
+        "//schema/capabilities:capabilities_c",
+    ],
+)
+
+cc_binary(
+    name = "LiteRtLm.dll",
+    linkshared = True,
+    deps = [
+        ":litert_lm_bridge",
+        "//c:engine",
+        "//schema/capabilities:capabilities_c",
+    ],
+)

native/stream_proxy/stream_proxy.c → native/bridge/litert_lm_bridge.c

@@ -3,13 +3,15 @@
 #include <stdlib.h>
 #include <string.h>
 
+// LiteRtLmBridge hosts downstream FFI bridge helpers. The stream_proxy_* exports
+// are the current streaming callback ABI and stay stable for compatibility.
 #if defined(_WIN32)
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
-#define STREAM_PROXY_EXPORT __declspec(dllexport)
+#define LITERT_LM_BRIDGE_EXPORT __declspec(dllexport)
 #else
 #include <dlfcn.h>
-#define STREAM_PROXY_EXPORT __attribute__((visibility("default")))
+#define LITERT_LM_BRIDGE_EXPORT __attribute__((visibility("default")))
 #endif
 
 typedef void (*stream_proxy_callback_t)(
@@ -57,7 +59,7 @@ static void stream_proxy_forward(
       error_copy);
 }
 
-STREAM_PROXY_EXPORT void *stream_proxy_load_global(const char *path) {
+LITERT_LM_BRIDGE_EXPORT void *stream_proxy_load_global(const char *path) {
   if (path == NULL) {
     return NULL;
   }
@@ -69,7 +71,7 @@ STREAM_PROXY_EXPORT void *stream_proxy_load_global(const char *path) {
 #endif
 }
 
-STREAM_PROXY_EXPORT void *stream_proxy_create(
+LITERT_LM_BRIDGE_EXPORT void *stream_proxy_create(
     stream_proxy_callback_t dart_callback,
     void *dart_data,
     stream_proxy_callback_t *out_proxy_callback) {
@@ -89,10 +91,10 @@ STREAM_PROXY_EXPORT void *stream_proxy_create(
   return context;
 }
 
-STREAM_PROXY_EXPORT void stream_proxy_delete(void *callback_data) {
+LITERT_LM_BRIDGE_EXPORT void stream_proxy_delete(void *callback_data) {
   free(callback_data);
 }
 
-STREAM_PROXY_EXPORT void stream_proxy_free_string(char *value) {
+LITERT_LM_BRIDGE_EXPORT void stream_proxy_free_string(char *value) {
   free(value);
 }