The first AI feature I shipped on a flat plan lost money on the third user who discovered it. Not slowly. Immediately. He was running a script through it on a loop because the UI did not stop him from doing that, and his single account burned through more in API costs that week than the feature was supposed to make in a month. I shipped the fix on a Sunday and rewrote the pricing on a Tuesday, and
I needed to coordinate background scripts running across different machines. The obvious answer was Redis. Everyone uses Redis for this. The tutorials all use Redis. The Stack Overflow answers all say "just use Redis." So I looked at what deploying Redis would actually cost me: A running Redis server I had to maintain A broker to connect workers to it Celery or RQ on top of that Memory-based stora