diff --git a/workflows/__tests__/differ-adapter.test.ts b/workflows/__tests__/differ-adapter.test.ts
index 3ab1209..9e50e73 100644
--- a/workflows/__tests__/differ-adapter.test.ts
+++ b/workflows/__tests__/differ-adapter.test.ts
@@ -15,8 +15,9 @@ function makeSpawn(result: MockSpawnResult) {
   return mock(async (_cmd: string, _args: string[], _opts: SpawnCliConfig) => result);
 }
 
+let tempDirCounter = 0;
 function tempDir(): string {
-  const dir = join(tmpdir(), `differ-test-${Date.now()}`);
+  const dir = join(tmpdir(), `differ-test-${Date.now()}-${tempDirCounter++}`);
   mkdirSync(dir, { recursive: true });
   return dir;
 }