Run, write, and debug tests — unit, integration, and end-to-end — in whatever framework the project already uses (Jest, Vitest, PHPUnit, Pytest, Go test, cargo test, RSpec, JUnit). Invoke when the user asks to test something, run the suite, add or fix tests, check coverage, or investigate a failing test. Skip when they want a code review rather than tests, or are asking how a test framework works in the abstract.
Write comprehensive, maintainable tests following TDD and AAA pattern. Use when writing unit tests, integration tests, setting up fixtures, mocking dependencies, or improving test coverage. Covers Python (pytest), TypeScript (Jest), Go (testing), and Rust (built-in + proptest). Do NOT use for mutation testing specifics (use mutation-testing skill).
Write unit tests, integration tests, and end-to-end tests. Use when implementing test suites, improving coverage, or ensuring code quality through testing.
Use when implementing any feature or bugfix and a test-driven approach is appropriate (red-green-refactor, seams-first), or when the user asks to find testing gaps, mutation test, or identify surviving mutants. Unit and integration tests only; browser journeys go to e2e-testing, test infrastructure to observability-quality, completion claims to gates.
Test scenarios, coverage analysis, test quality standards, and the mandatory test failure stop protocol. Load this skill for any task requiring test coverage.
Use when defining a test strategy, choosing layers, raising meaningful coverage, or fixing flaky suites — write tests with the feature, failing test first for bugs, QA audit before launch.
Write and review tests at all levels — Unit, Integration/Feature, and E2E — following Martin Fowler's testing pyramid. Use this skill when creating, modifying, or reviewing any test. Prevents test bloat, fragile assertions, and misplaced test levels. Adapts to any language/framework by following the decision flowchart and layer guidelines.
Produce proportionate automated evidence for software behavior. Use when writing or selecting tests, checking a regression or requirement, investigating a test failure, or assessing whether passing tests support a claim. Compose with implementation, debugging, browser QA, and code review as needed; do not take over their workflows or require tests for every trivial reversible edit.
How to test a full-stack app to a shipping bar, distilled from a real recruiter-led SaaS. Covers the test layers (unit, integration, contract, end-to-end, smoke, regression, security, performance, accessibility), what to run per change versus per release, the cross-viewport visual discipline (mobile, tablet, desktop, wide), the "verify for real" principle that a passing type-check is not a passing feature, hermetic stubbed e2e, tenant-isolation as a standing regression gate, and the file-upload and authorization security checks that keep a multi-tenant app safe. Load when writing tests, setting up a test harness, deciding what to verify before a commit, or reviewing whether a change is actually safe to ship. Fetch current framework docs with Context7 rather than from memory.
A folder with a SKILL.md file: a name, a description of when to use it, and instructions. Claude loads a skill only when the task matches its description.
How do I use one I find here?
Copy the folder into your project's .claude/skills/ directory, or into your own skills folder to use it everywhere.
What do the warnings mean?
We read each file for commands that read secrets, delete things or pipe downloads into a shell, and say so before you copy it. No warning is not a promise that a file is safe.
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Open a skill to see its discussion. Reports from people and their agents are coming.
cachewraithSkill
