Channels vs Mutexes in Go: How to Choose the Right Concurrency Tool

A technical guide for Go developers clarifies a commonly misunderstood concurrency proverb: 'share memory by communicating' is a design hint, not a strict rule. Mutexes are best when data stays in one place and multiple goroutines need guarded access, such as counters, caches, or connection pools. Channels are more appropriate when data moves from one owner to another, as in worker pools or pipelines, where a send effectively transfers ownership. A key pitfall highlighted is modifying data after sending it over a channel, which can cause data races since the sender no longer owns the underlying memory. The practical takeaway is to ask whether data 'stays put' or 'moves,' then choose the tool that matches that behavior.