Adaptive Rate Limiting with Redis and Lua

Making Rate Limiting Correct Under Concurrency Most rate limiting tutorials stop at the single-instance case. That’s fine for learning, but it breaks quickly in production. Once you have multiple instances and real traffic patterns, the problem changes. It’s no longer just about picking an algorithm — it’s about correctness under concurrency . This article walks through what actually goes wrong and how to fix it. The In-Memory Trap The first implementation most people write looks like this: keep