Unit Testing

Validate spec-implementation-test alignment and convergence. Checks spec completeness, implementation conformance, test coverage, and contract consistency. Use after implementation and tests are complete.

Validates compliance with 9 Constitutional Articles and Phase -1 Gates before implementation.Trigger terms: constitution, governance, compliance, validation, constitutional compliance,Phase -1 Gates, simplicity gate, anti-abstraction gate, test-first, library-first,EARS compliance, governance validation, constitutional audit, compliance check, gate validation.Enforces all 9 Constitutional Articles with automated validation:- Article I: Library-First Principle- Article II: CLI Interface Mandate- Article III: Test-First Imperative- Article IV: EARS Requirements Format- Article V: Traceability Mandate- Article VI: Project Memory- Article VII: Simplicity Gate- Article VIII: Anti-Abstraction Gate- Article IX: Integration-First TestingRuns Phase -1 Gates before any implementation begins.Use when: validating project governance, checking constitutional compliance,or enforcing quality gates before implementation.

Maintain approved technology stack including TypeScript/Python languages, React/Tailwind frontend, Node.js/FastAPI backend, PostgreSQL/Redis persistence, and Ansible infrastructure automation with enforced quality gates. Use this skill when selecting technologies, adding dependencies, configuring tooling, or ensuring infrastructure-as-code practices. Applies to package.json, requirements.txt, CI/CD pipelines, Ansible playbooks, linters, formatters, testing frameworks, and all technology choices requiring documented approval and migration strategies.

Guide experienced developers through REFACTOR phase of TDD cycle - improving code quality while maintaining green tests

Writing high-quality unit tests for JavaScript and TypeScript using Jest. Covers test structure (AAA pattern, USE naming), breaking dependencies (stubs, mocks, dependency injection), testing async code (promises, callbacks, timers), avoiding flaky tests, and test-driven development. Use when writing tests, debugging test failures, refactoring tests for maintainability, or questions about Jest, TDD, mocks, stubs, or test best practices.

Python project scaffolding and development with modern tooling. Use when creating new Python projects, setting up virtual environments, configuring dependencies, or working with Flask web applications. Triggers on mentions of Python setup, uv, Flask, pytest, or project initialization.

Create and maintain Roslyn source generators for compile-time code generation. Use when building incremental generators, designing pipelines with ForAttributeWithMetadataName, creating marker attributes, implementing equatable models, testing generators, or debugging generator performance issues.

Systematic methodology for debugging bugs, test failures, and unexpected behavior.Use when encountering any technical issue before proposing fixes. Covers root causeinvestigation, pattern analysis, hypothesis testing, and fix implementation.Use ESPECIALLY when under time pressure, "just one quick fix" seems obvious, oryou've already tried multiple fixes. NOT for exploratory code reading.

Comprehensive pre-production repository audit for preparing repos for public release. Use when the user wants to perform a "final sweep", "production check", "pre-release audit", or prepare a repository to be made public. Audits metadata files across all project types (Fabric mods, Node/npm, Go, Python, etc.) for correct username/organization, checks README links, and identifies leftover development artifacts like planning docs, test scripts, and temporary files. Interactive cleanup with user confirmation.

Use when writing or changing tests, adding mocks, or tempted to add test-only methods to production code - prevents testing mock behavior, production pollution with test-only methods, and mocking without understanding dependencies

Ensures comprehensive test coverage following Rails testing best practices

Work on Rust crates in packages/rust_viterbo. Use for crate layout, commands (fmt/clippy/test/bench), and coding conventions.

Use Open Props CSS custom properties for consistent design tokens. Use when setting up design systems, choosing spacing/color values, or wanting battle-tested CSS variables without heavy dependencies.

Execute E2E tests for the account service with proper server setup, test execution, and cleanup. Use when user requests account E2E testing, test execution, or running Playwright tests for account features.

Provides instructions to run the unit tests for project in a consistent and cost efficient way

Evaluates Catz Android coding challenge submissions against SWORD Health requirements. Use when reviewing or assessing this coding challenge. Produces a structured markdown report with seniority level assessment (Junior/Mid/Senior/Staff) and confidence rating, covering requirements compliance, architecture, code quality, testing, and documentation.

Validates Testing Phase completion before advancing to Finalization Phase. Checks test execution results, coverage targets, test quality, and environment health. Ensures 100% test pass rate required by quality gates.

Provides battle-tested patterns, best practices, and code examples for building Phaser 3 games. Use when writing game code, implementing game mechanics, setting up scenes, handling physics, animations, input, or any Phaser-related development. Covers architecture, performance, algorithms, and common pitfalls.

Your approach to handling testing pytest. Use this skill when working on files where testing pytest comes into play.

Increase test coverage from 0% to 80%+ in ANY project, ANY testing framework