Memory leaks in JavaScript don't announce themselves with an error. They show up as a heap that grows by 20MB per minute — invisible in a five-minute Lighthouse run, fatal in a six-hour production session. Why React apps leak: A useEffect that opens a WebSocket and never closes it on unmount. A setInterval without clearInterval in the cleanup return. A global Map that grows without bound. In each
State that survives a docker compose down is one of those things you don't think about, until your test suite needs it, your local dev needs it, and your CI pipeline absolutely doesn't. LocalStack handles persistence with one switch (PERSISTENCE=1) and it's a Pro-only feature. Floci ships four storage modes, all free, all in core, with per-service overrides. Pick the right tradeoff for the job.