diff --git a/.github/backend-matrix.yml b/.github/backend-matrix.yml
index 7df58bf6d..92293b764 100644
--- a/.github/backend-matrix.yml
+++ b/.github/backend-matrix.yml
@@ -4475,3 +4475,6 @@ includeDarwin:
   - backend: "speaker-recognition"
     tag-suffix: "-metal-darwin-arm64-speaker-recognition"
     build-type: "mps"
+  - backend: "ds4"
+    tag-suffix: "-metal-darwin-arm64-ds4"
+    lang: "go"
diff --git a/scripts/changed-backends.js b/scripts/changed-backends.js
index 62894bd9a..e8a68cf93 100644
--- a/scripts/changed-backends.js
+++ b/scripts/changed-backends.js
@@ -56,6 +56,11 @@ function inferBackendPathDarwin(item) {
   if (item.backend === "llama-cpp") {
     return `backend/cpp/llama-cpp/`;
   }
+  // ds4 is C++ too (built via `make backends/ds4-darwin`); the matrix entry
+  // carries lang=go for runner/toolchain selection, but the source is C++.
+  if (item.backend === "ds4") {
+    return `backend/cpp/ds4/`;
+  }
   if (!item.lang) {
     return `backend/python/${item.backend}/`;
   }