After shipping multiple apps, we learned one thing: Fast doesn't mean reckless. Here's our exact security checklist — broken down simply: 1/ API keys are ticking time bombs. Never, ever expose them on the frontend. → Store in Supabase Vault (encrypted) → Use edge functions for sensitive calls → Rotate keys every 90 days One exposed OpenAI key = $10K bill overnight. Ask me how I know. 2/ Enable RLS or get wrecked. Supabase tables are public by default. Without Row Level Security, anyone can: → Read your entire database → Delete all your users → Steal sensitive data Takes 2 minutes to enable. Saves you from bankruptcy. 3/ Rate limit everything. Supabase has auth limits built-in. But your custom endpoints? Wide open. Add these to every API route: → 100 requests per minute per IP → 1000 requests per hour per user → Exponential backoff for repeated failures One DDoS attack without limits = $5K in API costs. 4/ Audit like a hacker would. Open Chrome DevTools → Network tab. Look for: → Exposed API keys in requests → Overfetching (returning all records) → Missing auth checks → Unencrypted sensitive data If you can see it, hackers can exploit it. 5/ Use the right hosting. Netlify is great for MVPs. But lacks enterprise DDoS protection. For production apps: → Vercel or Cloudflare → Built-in firewalls → "Under Attack" mode → Geographic restrictions The $20/month difference saves you from $20K attacks. 6/ Authentication done right. Password auth = more problems. Use OAuth providers: → Google for B2B → Apple for consumer → GitHub for developers Less code. Better UX. Stronger security. 7/ The 3-layer defense. Never trust just one layer: → Frontend validation (UX) → API middleware checks (performance) → Database RLS policies (security) Each layer catches what the others miss. Here's the brutal truth: One security breach kills trust forever. We've seen startups die from a single hack. Not from the technical damage — from the reputation hit. So yes, ship fast with Lovable. But ship securely. Your users (and bank account) will thank you.