IMLAYLOW 👁️

25 signs your VIBE CODED app will BREAK at 500 users : Save this before you go live ! 1/ no load testing before launch > you don't know where it breaks because you've never pushed it > one traffic spike and you're debugging live in production 2/ session data stored in server memory > works on one instance > breaks the moment you need two 3/ file uploads going directly to your app server > disk fills up. server dies. files lost. > move uploads to object storage on day one 4/ synchronous email sending in API routes > slow email provider = slow API response for every request that triggers one > offload to a queue. always. 5/ no queue system for background tasks > everything blocking > one slow task pauses everything behind it 6/ hardcoded secrets in deployment scripts > sitting in your CI logs > visible to anyone with pipeline access 7/ single database with no read replica > all reads and writes hitting one machine > first real traffic spike kills query performance 8/ no CDN in front of static assets > every image served by your app server > 500 concurrent users = 500 image requests hitting your backend 9/ DB migrations running automatically on app start > two instances deploy at the same time > both run migrations. race condition. data inconsistency. 10/ no database backup ever tested with a restore > you have backups > you've never actually restored from one 11/ unindexed foreign key columns > every JOIN is a full scan > slow at 100 rows. broken at 100,000. 12/ no rate limiting anywhere > 500 users. one of them is a bot. > your server is now a bot server 13/ API responses with no compression > JSON payloads sent uncompressed > 10x the bandwidth they need to use 14/ no error alerting configured > app crashes at 3 AM > you find out when a user emails you at 9 AM 15/ transactions not used for multi-step writes > step 1 succeeds. app crashes. step 2 never runs. > data is now inconsistent permanently 16/ health check endpoint missing > load balancer sends traffic to crashed instances > users get 502s. you get support emails. 17/ memory leaks in long-running processes > memory grows slowly. server hits 100%. > everything grinds to a halt. restart. repeat. 18/ no graceful shutdown handling > deploy kills active requests > users mid-action get errors with no retry 19/ dependent on a third-party API with no fallback > that API goes down > your core feature goes down with it 20/ all logs written to local disk > logs rotate off > incident happens. no history to debug with. 21/ no circuit breaker on external calls > external service is slow > your thread pool fills waiting for it. everything queues. 22/ unparameterized search queries > search with any real data volume > 5-second response times at scale 23/ no connection timeout on outbound HTTP calls > external API hangs > your thread hangs with it. indefinitely. 24/ WebSockets not handled by a stateful service > horizontal scale breaks real-time features > every user gets disconnected 25/ no runbook for common incidents > something breaks at 2 AM > nobody knows what to do. everyone panics. you can ship fast and still build something that holds. bookmark this before you go live.