Kent C. Dodds·6wOffloading FFmpeg with Cloudflare
Kent C. Dodds shares how a long podcast episode caused his Fly.io primary server to hit 400-500% CPU load, forcing him to offload FFmpeg processing to Cloudflare Queues and Containers. The new architecture enqueues a job from the app, a Cloudflare Worker forwards it to a Container that runs FFmpeg, uploads results to R2, and POSTs a signed HMAC-SHA256 callback to the app. The post covers the before/after metrics (85% reduction in peak load), cost tradeoffs between Cloudflare and a dedicated Fly.io machine, and several implementation mistakes caught after the initial PR: a counterproductive local fallback, container lifecycle issues with sleepAfter, and a queue worker that blocked for the full transcode duration. The conclusion reinforces a 'start simple, iterate when reality demands it' philosophy.