Cloudflare Workers developers must update their build environments as version 1 of the Vitest integration is now published under a new package name: @cloudflare/vitest-plugin. The former identifier, @cloudflare/vitest-pool-workers, has been deprecated in favor of this updated nomenclature.
Migration Requirements
The core configuration API remains unchanged; however, existing projects require specific updates to their package.json files and import statements. To automate the transition across npm, yarn, or pnpm environments without manual intervention, practitioners should execute the provided codemod tool:
- Run
npx @cloudflare/codemods vitest:pool-workers-to-vitest-plugin
This utility automatically rewrites dependency references and adjusts TypeScript configuration entries to align with the new package identity.
Maintaining Test Isolation
For outbound request mocking within Workers test suites, engineers should continue utilizing the @msw/cloudflare integration. This ensures that network simulation logic remains decoupled from the Vitest runner itself while preserving isolation guarantees for unit tests and end-to-end scenarios.
What This Means For Practitioners
This renaming signals a stabilization of the testing ecosystem around Cloudflare Workers, moving away from "pool" terminology toward standard plugin architecture patterns. Platform teams should update their internal CI/CD libraries immediately to prevent build failures in automated pipelines.
