Vitest

This generates a complete Vitest setup tailored to your project type. It detects whether you're running Cloudflare Workers, React, Hono APIs, or a library, then scaffolds the right config, test utilities, and a working sample test. The skill extends existing vite.config.ts files instead of creating conflicts, handles Jest migrations, and picks a real file from your codebase to demonstrate testing patterns. It's thorough about the details that break most test setups: TypeScript globals, jsdom vs node environments, Workers pool configuration. Use it when you're starting fresh with Vitest or fixing a broken test infrastructure. The generated files actually run, which is rarer than it should be.

skills.sh installs: 1.8K
GitHub stars: 1.1K
last updated: Aug 21, 2026

View on GitHub

Install

$ npx -y skills add jezweb/claude-skills --skill vitest --agent claude-code

Installs into .claude/skills of the current project.

Files

Vitest Setup

Detect the project type, generate the right Vitest configuration, and produce working test infrastructure. Not a reference card — this skill creates files.

Workflow

Detect — scan the project to determine type and existing setup
Configure — generate vitest.config.ts tailored to the environment
Scaffold — create test setup, utilities, and a sample test
Wire up — add package.json scripts and TypeScript config

Step 1: Detect Project Type

Read these files to determine the project:

package.json          → dependencies, scripts, type field
tsconfig.json         → paths, compiler options
wrangler.toml         → Cloudflare Workers project
vite.config.ts        → existing Vite setup (extend, don't replace)
vitest.config.ts      → already configured? just fill gaps
jest.config.*         → migration candidate
src/                  → source structure

Classify as one of:

SKILL.md on GitHub