Jest

Write and run tests across languages and frameworks. Use when setting up test suites, writing unit/integration/E2E tests, measuring coverage, mocking dependencies, or debugging test failures. Covers Node.js (Jest/Vitest), Python (pytest), Go, Rust, and Bash.

NestJS best practices and architecture patterns for building production-ready applications. This skill should be used when writing, reviewing, or refactoring...

Unit, integration, and E2E testing patterns with framework-specific guidance. Use when asked to "write tests", "add test coverage", "testing strategy", "test this function", "create test suite", "fix flaky tests", or "improve test quality".

Test REST APIs with customizable headers, authentication, and request bodies. Use when debugging API endpoints, testing authentication flows, validating resp...

Perform structured HTTP/HTTPS requests (GET, POST, PUT, DELETE) with custom headers and JSON body support. Use for API testing, health checks, or interacting...

Testing patterns for Zod schemas using Jest and Vitest. Covers schema correctness testing, mock data generation, error assertion patterns, integration testin...