Vitest

Vitest 4 is out! - Browser Mode is Stable - Visual Regression Testing - Improved Debugging - Pool Stabilization - New APIs - Bug Fixes Stay updated with our blog post: vitest.dev/blog/vitest-4

VoidZero is joining Cloudflare. Our mission stays the same: to make JavaScript developers more productive than ever before. Vite, Vitest, Rolldown, Oxc, and Vite+ remain MIT-licensed. Evan and the VoidZero team will continue leading them. Cloudflare shares our commitment to open source. Together, we can keep investing in the tooling developers rely on every day, while bringing the Vite ecosystem and Cloudflare’s platform even closer together.

We've published a Browser Mode security advisory. CDP-capable providers like Playwright Chromium with the browser API exposed to the network allowed attackers to run code on the host. Update vitest/browser to 5.0.0-beta.4, 4.1.8, or 3.2.6. Vite+ users: Upgrade to 0.1.24

We’re launching early access for Vitest visual testing with Chromatic! ⚡️ Built with @vitest_dev core maintainer Ari Perkkio, Chromatic adds visual testing to the browser tests you already write. 🧵 (1/4)

🚨 We are publishing Vitest 4.1.6 and Vitest 5.0.0-beta.3 to resolve recent vulnerabilities: - `--api` and `--ui` exposed arbitrary files to the network - `--api` allowed arbitrary execution - `?otelCarrier` XSS More information on our GitHub security page

Read our announcement post for all the details vitest.dev/blog/vitest-4-…

Vitest 4.1 is out! 🚀 ✅ Vite 8 support from day 1 🏷️ Test tags to organize, filter & apply shared options 🪝 New hooks for easier tracing, transactions and AsyncLocalStorage 🔍 Async leak detection 🤖 Agent reporter to reduce token usage And much more!

@mhsnook @tannerlinsley @ashishxcode @tan_stack

@tannerlinsley @ashishxcode @tan_stack Any interest in making a testing framework? with AI-driven velocity increases... tests are more important than ever, and playwright still feels like 2018 tech. (And I think the existence of Vite + server functions makes for some interesting possibilities)

.@Tan_Stack CU Phase 1 - Table - Query - Virtual - Form - Store Phase 2 - Router - Start - DB - Pacer Phase 3 - Devtools - AI - CLI - Hotkeys Phase 4 ...

Flaky tests and memory leaks are the worst. @vitest_dev now has a --detect-async-leaks flag that catches uncleared intervals, lingering servers, and other async operations leaking across your tests. ⚠️ Don't run it on every run though. Use it to audit your test suite, then clean things up. Available in the latest 4.1 beta. Big shout out to Ari from the Vitest team for landing this PR! 🔥

Tests. Vitest's browser mode is stable since Vitest 4.0. Now you can be sure that your tests pass in an *actual* browser environment. vitest.dev/guide/browser/

✨ What's New in ViteLand: January 2026 Recap ◆ Unified redesign across all VoidZero sites ◆ @vite_js crossed 3 billion npm downloads ◆ @rolldown_rs reached RC status ◆ Lazy Barrel Optimization landed in Rolldown ◆ Oxfmt hit 100% Prettier conformance ◆ Oxlint gets a dynamic .ts config ◆ ...and much more 👀 Full recap below!

The first beta for @vitest_dev 4.1 is out! 🧪 What's new: ◆ Chai-style spy assertions (`toHaveBeenCalled`, etc.) ◆ `userEvent.wheel()` for browser mode ◆ Enhanced retry options for flaky tests ◆ Disposable returned from `doMock()` ◆ Respecting coverage ignore start/stop hints ◆ and more 👀 Try now by installing vitest@beta

New Year. New Look. Same Mission. Make JavaScript developers more productive than ever before

Want to speed up subsequent @vitest_dev runs? Then try out the new experimental file-system based cache ✨ ⋄ Caches transformed modules ⋄ Does *not* work with browser mode yet ⋄ Can be manually cleared via `vitest --clearCache` More in the docs #experimental-fsmodulecache" target="_blank" rel="nofollow noopener">vitest.dev/config/experim…

I started a proof of concept to integrate the standard schema natively into @vitest_dev It's currently being discussed integrating this directly into `toEqual()`, creating a new custom matcher like `toEqualSchema()` or an asymmetric matcher like `schemaMatching()`

What's new in ViteLand? Our August 2025 recap is out 👣 Big steps for Oxlint: Type-aware linting preview & custom JS plugins roadmap 🖼️ @vitest_dev has visual regression support in beta ⏩ Native plugins enabled by default in rolldown-vite 🤌 Smaller bundles due to @rolldown_rs and Oxc 👀 and more

⚡ Speaker highlight: Jessica Sachs, FOSS Nerd at @HeroDevs The Vitest Browser mode is one of the most exciting features of @vitest_dev! @_jessicasachs will reveal what makes it so powerful, moving beyond JSDOM. You’ll learn how you can use it for component testing and even cases beyond that - and which new capabilities the browser mode got (looking at you visual regression testing 👀) A game-changer for testing! ✅ Watch the talk live - viteconf.amsterdam