vitest

Run Jest-compatible unit tests with native ESM and TypeScript in Vite projects.

16|Updated Feb 22, 2026

Search Tags:#typescript #vitest #testing #vite #snapshots #esm #jest-compatible

Ready to run

npx skills add https://github.com/Pouryaak/LokulMem --skill vitest-pouryaak

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: vitest
Source: https://github.com/Pouryaak/LokulMem/tree/main/.claude/skills/vitest
Command: npx skills add https://github.com/Pouryaak/LokulMem --skill vitest-pouryaak

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

Vitest provides fast, browser-native unit testing for modern web apps built with Vite, offering a Jest-compatible API and native ESM, TypeScript, and JSX support.

Core Features & Use Cases

Jest-compatible API with native ESM, TypeScript, and JSX support
Tight Vite integration for fast, deterministic tests, coverage, mocks, and snapshots
Supports multi-project configurations, worker pools, and snapshot testing
Common use cases include unit tests, integration tests, mocking, coverage reports, and test context/fixtures

Quick Start

Install Vitest in your project and run tests with vitest to execute your test suite.

Frequently Asked Questions about vitest

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

FAQPage Schema

How do I run unit tests for a Vite app with TypeScript and ESM?▼

Vitest provides fast unit tests for Vite apps with native ESM, TypeScript, and JSX support. Install Vitest in your project and run the vitest command to execute your test suite with a Jest-compatible API.

Can I use Vitest for testing across React, Vue, and Svelte projects?▼

Vitest can be applied to Vite-based projects across React, Vue, Svelte, and other frameworks. It supports multi-project configurations, enabling unit tests, mocks, coverage, and snapshot testing within a single setup.

Does Vitest work as a Jest-compatible replacement for snapshot testing?▼

Vitest offers a Jest-compatible API with native ESM and TypeScript support, including snapshot testing capabilities. It integrates tightly with Vite to provide fast, deterministic test execution and coverage reports.

What is the best way to configure parallel test execution in a Vite project?▼

Vitest meets requirements for configuration via vitest.config.ts, supporting worker pools for parallel test execution. This Vite integration ensures fast test runs while utilizing fixture and mocking utilities.

Why does my testing setup require native ESM support for modern web apps?▼

Native ESM support is required for fast, browser-native unit testing in modern web apps. Vitest solves this by providing a Jest-compatible API that natively handles ESM, TypeScript, and JSX within Vite projects.

Do I need Vite to use Vitest for unit tests and mocking?▼

Vitest is designed for tight Vite integration to deliver fast, deterministic tests. It leverages the Vite configuration to provide unit tests, mocks, coverage reports, and test context fixtures across supported frameworks.