# Vitest v4.1.0 — Release & Upgrade Intelligence
- **Product:** Vitest (https://vitest.dev)
- **Version:** v4.1.0
- **Released:** Mar 12, 2026
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/vitest/updates/v4.1.0/
## Executive Summary (TL;DR)
Vitest v4.1.0. Source highlight: This release page lists all changes made to the project during the 4.1 beta. To get a review of all the new features, read our blog post.
## New Features
- Return a disposable from doMock() - by @kirkwaiblinger in https://github.com/vitest-dev/vitest/issues/9332 (e3e65)
- Added chai style assertions - by @ronnakamoto and @sheremet-va in https://github.com/vitest-dev/vitest/issues/8842 (841df)
- Update to sinon/fake-timers v15 and add `setTickMode` to timer controls - by @atscott and @sheremet-va in https://github.com/vitest-dev/vitest/issues/8726 (4b480)
- Expose matcher types - by @sheremet-va in https://github.com/vitest-dev/vitest/issues/9448 (3e4b9)
- Add `toTestSpecification` to reported tasks - by @sheremet-va in https://github.com/vitest-dev/vitest/issues/9464 (1a470)
- Show a warning if `vi.mock` or `vi.hoisted` are declared outside of top level of the module - by @sheremet-va in https://github.com/vitest-dev/vitest/issues/9387 (5db54)
## Improvements
- **pretty-format**: Combine DOMElement plugins - by @sheremet-va in https://github.com/vitest-dev/vitest/issues/9581 (da85a)
## Bug Fixes
- Support vite 8 beta, fix type issues in the config with different vite versions - by @sheremet-va in https://github.com/vitest-dev/vitest/issues/9587 (99028)
- Deprecate several vitest/* entry points - by @sheremet-va in https://github.com/vitest-dev/vitest/issues/9347 (fd459)
- Use `meta.url` in `createRequire` - by @sheremet-va in https://github.com/vitest-dev/vitest/issues/9441 (e3422)
- Preact browser mode init example of render function not async - by @WuMingDao in https://github.com/vitest-dev/vitest/issues/9375 (2bea5)
- Deprecate unused types in matcher context - by @sheremet-va in https://github.com/vitest-dev/vitest/issues/9449 (20f87)
- Handle `external/noExternal` during `configEnvironment` hook - by @hi-ogawa and **Claude Opus 4.6** in https://github.com/vitest-dev/vitest/issues/9508 (59ea2)