diff --git a/src/extension-api-v2/__tests__/bc-02.migration.test.ts b/src/extension-api-v2/__tests__/bc-02.migration.test.ts
index dfa121cb5f..a4ec540305 100644
--- a/src/extension-api-v2/__tests__/bc-02.migration.test.ts
+++ b/src/extension-api-v2/__tests__/bc-02.migration.test.ts
@@ -131,7 +131,7 @@ describe('BC.02 migration — node lifecycle: teardown', () => {
       const v1Ticks = vi.fn()
       const v2Ticks = vi.fn()
 
-      let v2Handle: number | undefined
+      let v2Handle: ReturnType<typeof globalThis.setInterval> | undefined
 
       // v1 pattern: manual tracking
       const v1Handle = setInterval(v1Ticks, 100)
diff --git a/src/extension-api-v2/__tests__/bc-02.v2.test.ts b/src/extension-api-v2/__tests__/bc-02.v2.test.ts
index 18c1fd2047..481636f91c 100644
--- a/src/extension-api-v2/__tests__/bc-02.v2.test.ts
+++ b/src/extension-api-v2/__tests__/bc-02.v2.test.ts
@@ -182,7 +182,7 @@ describe('BC.02 v2 contract — node lifecycle: teardown', () => {
     it('interval cleared in onScopeDispose does not fire after unmount', () => {
       vi.useFakeTimers()
       const intervalCallback = vi.fn()
-      let handle: number | undefined
+      let handle: ReturnType<typeof globalThis.setInterval> | undefined
 
       const { unmount } = mountNode(() => {
         handle = setInterval(intervalCallback, 100)