vitest

Run Jest-compatible unit tests in Vite projects with Vitest.

Updated Mar 25, 2026

Search Tags:#typescript #vitest #testing #jest #vite #mocking #snapshot

Ready to run

npx skills add https://github.com/MileniumTick/skills --skill vitest-mileniumtick

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: vitest
Source: https://github.com/MileniumTick/skills/tree/main/skills/vitest
Command: npx skills add https://github.com/MileniumTick/skills --skill vitest-mileniumtick

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

Vitest provides fast, Jest-compatible unit testing for Vite projects, enabling you to write tests, mocks, and coverage with a cohesive API.

Core Features & Use Cases

Jest-compatible API with native ESM, TypeScript, and JSX support
Vite-native test runner with fast feedback, smart watch mode, and parallel execution
Built-in coverage, snapshot testing, mocking utilities, and project configuration
Supports multi-project setups and plugin ecosystem integration

Quick Start

Install Vitest, create a vitest.config.ts if needed, and run vitest to execute your tests.

Frequently Asked Questions about vitest

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I run Jest-compatible unit tests in a Vite project?▼

Vitest provides fast, Jest-compatible unit testing for Vite projects with native ESM and TypeScript support. It uses a Vite-native test runner to execute tests with a cohesive API, enabling you to write tests, mocks, and coverage directly within your existing development workflow.

Does Vitest support native ESM and TypeScript out of the box?▼

Yes, Vitest supports native ESM, TypeScript, and JSX out of the box. It leverages your Vite configuration to process these formats natively, eliminating the need for complex transpilation setups before executing your unit test suites.

What is the best way to set up mocking and snapshot testing in Vite?▼

Vitest includes built-in mocking utilities and snapshot testing features. You can configure these testing capabilities along with coverage in your vitest.config.ts file, providing a cohesive API for validating frontend and full-stack codebases.

Can I use Vitest for multi-project setups and plugin integration?▼

Yes, Vitest supports multi-project setups and plugin ecosystem integration. This allows you to organize and run tests across different packages or configurations within a single repository while maintaining fast feedback and parallel execution.

Vitest vs Jest: which testing framework is better for Vite-based projects?▼

Vitest is designed specifically for Vite-based projects, offering faster feedback through smart watch mode and parallel execution. While Jest is compatible, Vitest provides native ESM, TypeScript, and JSX support without extra configuration overhead.