Use when reviewing PRs, examining code changes, running `gh pr diff`, or when asked for code review. Also trigger after completing a feature implementation when review is needed before merging. NOT for test quality (see test-design).
Git conventional commits — use this skill whenever authoring new git commits from working tree changes, writing commit messages, or planning how to organize changes into commits. Also trigger when grouping changes into logical commits, cleaning up a messy working tree, or when any agent needs to create commit messages as part of a workflow. NOT for non-authoring git operations (branching, merging, rebasing, cherry-picking, reverting, squashing, resolving conflicts, creating PRs, git configuration, or exploring git history).
You MUST consult this skill when choosing a concurrency architecture: thread topology (thread-per-core, work-stealing, event loop), unit of concurrency (actors, goroutines, state machines), or inter-component communication model (message passing, channels, shared memory). Also trigger when designing fault isolation boundaries, supervision trees, or backpressure propagation; when scaling a single-threaded design to multi-core; or when choosing between actor vs CSP channel models. NOT for lock primitive implementation, network protocol state machines, database connection pooling, language-specific async runtime config (tokio, asyncio), compute parallelism (SIMD, GPU), or distributed consensus (Raft, Paxos).
You MUST consult this skill when writing, reviewing, or fixing tests at any level (unit, integration, e2e). Also trigger when delivering features where tests are expected, when tests break on refactors, or when asking what makes a good test — even if 'write tests' wasn't explicitly requested. NOT for TDD workflow (see test-driven-development), test infrastructure setup (CI config, test runners), or diagnosing production code bugs.
You MUST consult this skill when writing, reviewing, or generating Odin code. Also trigger on .odin files, Odin package structure, allocator patterns, or any Odin-specific design question. LLMs have significant knowledge gaps about Odin — this skill fills them. NOT for general systems programming advice or C/Zig/Rust unless comparing to Odin idioms.
You MUST consult this skill when writing, reviewing, or designing code. Also trigger when code seems verbose or over-documented (unnecessary wrappers, comments restating the code), when design behavior is ambiguous (what should happen on empty input, which error to propagate), or when conventions are silently violated without explanation. NOT for debugging existing errors, language syntax questions, framework setup (CI/CD, database migrations), performance benchmarking, test quality criteria (see test-design), API surface conventions (see api-design), or abstract pattern theory discussions.
Application-level structural patterns -- layering, business logic organization, data access strategy, domain modeling, and cross-boundary communication. Use when designing a new service, choosing how to structure an application, or reviewing code for architectural smells (logic in controllers, no domain boundary, tangled data access). NOT for code-level design (see software-design), API surface conventions (see api-design), or infrastructure/deployment architecture.
You MUST use this before any creative work — creating features, building components, adding functionality, or modifying behavior. Also trigger when the user mentions brainstorming, wants to think through a design, stress-test a plan, or says 'grill me'. NOT for debugging, code review, writing tests, committing, or mechanical refactors (renaming, version bumps, config changes).