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Vitest vs Bun: catalog facts
Vitest	Bun
Best for: JavaScript and TypeScript projects, especially those built with Vite	Best for: Replacing Node, npm, a bundler and a test runner with a single faster tool
Free Free and open source, funded by sponsors.	Free Free and open source. The runtime core is MIT licensed with some bundled components under other licences including… Full pricing details for Bun Free and open source. The runtime core is MIT licensed with some bundled components under other licences including GPL-2.0.
Windows, macOS, Linux, Command line	Windows, macOS, Linux, Command line
Reuses Vite config and plugins for tests Jest-compatible API eases migration All 4 strengths for Vitest Reuses Vite config and plugins for tests Jest-compatible API eases migration Smart watch mode reruns only related tests ESM, TypeScript and JSX out of the box	Runtime, bundler, test runner and package manager in one executable Much faster startup and installs than the Node and npm equivalents All 4 strengths for Bun Runtime, bundler, test runner and package manager in one executable Much faster startup and installs than the Node and npm equivalents Runs TypeScript directly with no build step Designed as a drop-in for Node.js, so existing projects often work unchanged
Limited to JavaScript and TypeScript projects Large Jest suites may still need adjustments when migrating	Node compatibility is good but not complete; packages using deep internals can break Younger than Node, so fewer production deployments to learn from All 4 limitations for Bun Node compatibility is good but not complete; packages using deep internals can break Younger than Node, so fewer production deployments to learn from Linux kernel 5.6 or later is strongly recommended, with 5.1 the minimum Older x64 CPUs can hit illegal instruction errors without a baseline build
Downloadable app	Downloadable app
Open source	Open source
License: MIT	License: MIT
No account needed	No account needed
Offline features available	Offline features available
Official website Full listing and sources Sources for Vitest vitest.dev Catalog checked October 2, 2026	Official website Full listing and sources Sources for Bun github.com/oven-sh/bun Catalog checked September 21, 2026

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