20 things that make your VIBE CODED app a SINKING SHIP : 1/ no rate limiting on API routes > anyone can spam your backend into a $500 bill overnight 2/ auth tokens stored in localStorage > one XSS attack = every single user account compromised 3/ no input sanitisation on forms > SQL injection still works in 2026. your AI didnt tell you that. 4/ hardcoded API keys in the frontend > someone WILL find them within 48 hours of launch 5/ stripe webhooks with no signature verification > anyone can fake a successful payment event 6/ no database indexing on queried fields > works fine at 100 users. completely dies at 1,000. 7/ no error boundaries in the UI > one crash = white screen = user never comes back 8/ sessions that never expire > stolen token = permanent access to that account. forever. 9/ no pagination on database queries > one fetch loads your entire database into memory 10/ password reset links that dont expire > old email in someones inbox = instant account takeover 11/ no environment variable validation at startup > app silently breaks in production with zero error message 12/ images uploaded directly to your server > no CDN = 8 second load times + massive hosting bill 13/ no CORS policy > any website on the internet can make requests to your API 14/ emails sent synchronously in request handlers > one slow SMTP server = your entire app hangs 15/ no database connection pooling > first traffic spike = database crashes 16/ admin routes with no role checks > any logged in user can access your admin panel 17/ no health check endpoint > your app goes down silently. you find out from a client. 18/ no logging in production > when something breaks you have zero idea where or why 19/ no backup strategy on your database > one bad migration = all your user data. gone. 20/ no TypeScript on AI generated code > AI writes confident, wrong, untyped code and you ship it anyway