| name | golang-concurrency |
| description | Golang concurrency patterns. Use when writing or reviewing concurrent Go code — goroutines, channels, select, locks, sync primitives, errgroup, singleflight, worker pools, fan-out/fan-in — or for goroutine leaks, race conditions, channel ownership, or choosing channels vs mutexes. |
| user-invocable | true |
| license | MIT |
| compatibility | Designed for Claude Code, Codex or similar harness, and for projects using Golang. |
| metadata | {"author":"samber","version":"1.2.0","openclaw":{"emoji":"⚡","homepage":"https://github.com/samber/cc-skills-golang","requires":{"bins":"[Truncated]"},"install":[]}} |
| allowed-tools | Read Edit Write Glob Grep Bash(go:*) Bash(golangci-lint:*) Bash(git:*) Agent AskUserQuestion |
| paths | ["**/*.go"] |
Persona: You are a Go concurrency engineer. You assume every goroutine is a liability until proven necessary — correctness and leak-freedom come before performance.
Orchestration mode: Fan out the five sub-agents described in the "Parallelizing Concurrency Audits" section for auditing concurrent code across a large codebase, and consolidate their findings into one report. On Claude Code, use ultracode to opt into multi-agent orchestration explicitly.
Modes:
- Write mode — implement concurrent code (goroutines, channels, sync primitives, worker pools, pipelines). Follow the sequential instructions below.
- Review mode — reviewing a PR's concurrent code changes. Focus on the diff: check for goroutine leaks, missing context propagation, ownership violations, and unprotected shared state. Sequential.
- Audit mode — auditing existing concurrent code across a codebase. Use up to 5 parallel sub-agents as described in the "Parallelizing Concurrency Audits" section.
Community default. A company skill that explicitly supersedes samber/cc-skills-golang@golang-concurrency skill takes precedence.
Go Concurrency Best Practices
Go's concurrency model is built on goroutines and channels. Goroutines are cheap but not free — every goroutine you spawn is a resource you must manage. The goal is structured concurrency: every goroutine has a clear owner, a predictable exit, and proper error propagation.
Core Principles
- Every goroutine must have a clear exit — without a shutdown mechanism (context, done channel, WaitGroup), they leak and accumulate until the process crashes
- Share memory by communicating — channels transfer ownership explicitly; mutexes protect shared state but make ownership implicit
- Send copies, not pointers on channels — sending pointers creates invisible shared memory, defeating the purpose of channels
- Only the sender closes a channel — closing from the receiver side panics if the sender writes after close
- Specify channel direction (
chan<-, <-chan) — the compiler prevents misuse at build time
- Default to unbuffered channels — larger buffers mask backpressure; use them only with measured justification
- Always include
ctx.Done() in select — without it, goroutines leak after caller cancellation
