Concurrency Patterns

This is your reference for implementing thread-safe concurrent code across JavaScript, Python, and simulated Go patterns. It covers promise pools, mutexes, semaphores, worker pools, and async/await coordination with working examples in each language. The promise pool and mutex implementations are solid starting points if you need to limit concurrency or prevent race conditions. Most useful when you're building systems that do parallel processing or need to coordinate multiple async operations without hammering resources. The guides are implementation-focused rather than theory-heavy, which means you can copy and adapt quickly. Just remember that concurrent code needs real testing under load, not just unit tests.