diff --git a/src/plugins/bundled-runtime-deps.test.ts b/src/plugins/bundled-runtime-deps.test.ts
index 360a2978786..ce23de0f8ae 100644
--- a/src/plugins/bundled-runtime-deps.test.ts
+++ b/src/plugins/bundled-runtime-deps.test.ts
@@ -240,6 +240,30 @@ describe("installBundledRuntimeDeps", () => {
     expect(fs.readFileSync(chunkPath, "utf8")).toContain("same-file");
   });
 
+  it("replaces stale mirror symlinks when materializing chunks", () => {
+    const tempDir = makeTempDir();
+    const sourcePath = path.join(tempDir, "dist", "accounts.js");
+    const targetPath = path.join(tempDir, "stage", "dist", "accounts.js");
+    fs.mkdirSync(path.dirname(sourcePath), { recursive: true });
+    fs.mkdirSync(path.dirname(targetPath), { recursive: true });
+    fs.writeFileSync(
+      sourcePath,
+      [
+        `//#region extensions/slack/src/accounts.ts`,
+        `export const marker = "source";`,
+        `//#endregion`,
+        "",
+      ].join("\n"),
+      "utf8",
+    );
+    fs.symlinkSync(sourcePath, targetPath, "file");
+
+    materializeBundledRuntimeMirrorDistFile(sourcePath, targetPath);
+
+    expect(fs.lstatSync(targetPath).isSymbolicLink()).toBe(false);
+    expect(fs.readFileSync(targetPath, "utf8")).toContain("source");
+  });
+
   it("uses a real write probe for runtime dependency roots", () => {
     const accessSpy = vi.spyOn(fs, "accessSync").mockImplementation(() => undefined);
     const mkdirSpy = vi.spyOn(fs, "mkdtempSync").mockImplementation(() => {
diff --git a/src/plugins/bundled-runtime-deps.ts b/src/plugins/bundled-runtime-deps.ts
index d3ba071d0f6..252ba6ec2e5 100644
--- a/src/plugins/bundled-runtime-deps.ts
+++ b/src/plugins/bundled-runtime-deps.ts
@@ -91,7 +91,10 @@ export function materializeBundledRuntimeMirrorDistFile(
     return;
   }
   try {
-    if (fs.realpathSync(sourcePath) === fs.realpathSync(targetPath)) {
+    if (
+      fs.realpathSync(sourcePath) === fs.realpathSync(targetPath) &&
+      !fs.lstatSync(targetPath).isSymbolicLink()
+    ) {
       return;
     }
   } catch {