copy

Skill

Skill

Skill

Skill

Idiomatic Go testing with the stdlib `testing` package and the go-testdeep assertion library. ALWAYS use this skill when writing or reviewing Go tests — table-driven tests with `map[string]testCase`, `t.Run` subtests, `t.Helper()` for assertion helpers, `t.Cleanup`, `t.Parallel`, integration test gating with environment variables, benchmarks (`testing.B`), fuzz tests, go-testdeep operators (`td.Cmp`, `td.CmpError`, `td.CmpNoError`, `td.Struct`, `td.Smuggle`, `td.Between`, `td.Re`, `td.Require`), and the third-party-frameworks debate (go-testdeep when deps are allowed, stdlib-only for dependency-free projects, never testify). Pair with go-sql for testing DB code with sqlc's `Querier` interface, go-http for `httptest` patterns, and go-concurrency for race-detector usage.

Comprehensive macOS and iOS development expertise covering Swift best practices, SwiftUI design patterns, Human Interface Guidelines, Apple frameworks, and performance optimization. Use when developing native Apple applications, implementing SwiftUI interfaces, working with Apple frameworks (Foundation, UIKit, AppKit, Core Data, CloudKit, etc.), optimizing app performance, following HIG principles, or writing production-quality Swift code for iOS, macOS, watchOS, or tvOS platforms.

Skills that we use to build our software.

Disciplined Go concurrency. ALWAYS use this skill when writing or reviewing Go code that touches goroutines, channels, `context.Context`, `sync.WaitGroup`, `sync.Mutex` / `sync.RWMutex`, `sync.Once`, `errgroup.Group`, worker pools, fan-out/fan-in pipelines, request cancellation, timeouts, deadlines, or any "run this in the background" pattern. Also use when debugging deadlocks, goroutine leaks, race conditions, or channel-related bugs. Pair with go-errors for error propagation across goroutines.

Idiomatic Go style: naming, package and file organization, interfaces, documentation, generics, iterators, range-over-int, performance, dependency management, and common pitfalls. ALWAYS use this skill when writing or reviewing Go code for general style and idioms — questions about naming conventions, where to put a type, when to use generics vs `any`, how to size interfaces, godoc comments, the `internal/` package, struct literal initialization, slice/map gotchas, loop-variable capture, defer timing, or "is this idiomatic Go?". Pair with go-errors, go-concurrency, go-testing, go-logging, go-http, go-cli, go-sql, or go-lint when those concerns dominate the task.

Writing, reviewing, refactoring, debugging, or designing Go code — backends, microservices, APIs, CLI tools, daemons, workers, data pipelines, libraries. Umbrella router that delegates to focused sibling Go skills.