diff --git a/spinifex/services/spinifexui/frontend/src/test/setup.ts b/spinifex/services/spinifexui/frontend/src/test/setup.ts
index 560b3a75c..22617c79a 100644
--- a/spinifex/services/spinifexui/frontend/src/test/setup.ts
+++ b/spinifex/services/spinifexui/frontend/src/test/setup.ts
@@ -1,3 +1,4 @@
+import type * as TestingLibraryReact from "@testing-library/react"
 import { cleanup } from "@testing-library/react"
 import "@testing-library/jest-dom/vitest"
 import { afterEach, vi } from "vitest"
@@ -8,6 +9,19 @@ afterEach(() => {
   cleanup()
 })
 
+// waitFor wakes on DOM mutations, otherwise it polls every 50ms. renderHook
+// tests settle without touching the DOM, so each one pays a full tick.
+vi.mock("@testing-library/react", async (importOriginal) => {
+  const actual = await importOriginal<typeof TestingLibraryReact>()
+  return {
+    ...actual,
+    waitFor: async (
+      callback: Parameters<typeof actual.waitFor>[0],
+      options?: Parameters<typeof actual.waitFor>[1],
+    ) => await actual.waitFor(callback, { interval: 1, ...options }),
+  }
+})
+
 // Components sign requests with the region the server reports, which the app
 // normally loads before rendering. Seed it through the real code path so every
 // component test has one without stubbing fetch itself.
diff --git a/spinifex/services/spinifexui/frontend/vite.config.ts b/spinifex/services/spinifexui/frontend/vite.config.ts
index 0537e49e3..e38a04b5f 100644
--- a/spinifex/services/spinifexui/frontend/vite.config.ts
+++ b/spinifex/services/spinifexui/frontend/vite.config.ts
@@ -42,6 +42,7 @@ export default defineConfig(({ mode }) => ({
     environment: "happy-dom",
     setupFiles: "./src/test/setup.ts",
     clearMocks: true,
+    pool: "threads",
     coverage: {
       include: ["src/**/*.{ts,tsx}"],
       exclude: [