750 Free Hours a Month, but a Month Is 730: 3 Free-Tier Mistakes That Took Down My App

🚢 #BuildInPublic for the RevenueCat Shipaton 2026 . RentDera is my Shipaton entry, and I'm sharing the whole journey — the wins and the 5 AM disasters like this one. This is one chapter of that trail. At 9 PM on September 10th, 2026 , Render emailed me to say my production services had been suspended. At 5 AM on September 11th , I published v1.2.0 to the Play Store. In between was the worst night of this project so far — and it was entirely my own doing. Three separate mistakes, each individually reasonable, stacked into an outage that took down a shared identity service, a product API, and a mail service at once. Here's all three, with the numbers. The 30-second version (if you only read this far) Free tiers are metered. Render gives ~750 machine-hours/month across a workspace; a month is ~730 hours. Keeping one service awake 24/7 eats almost the entire budget. A keep-alive cron is a trap. Pinging services to stop them sleeping doesn't outsmart the platform — it just spends the free quota faster, and then everything gets suspended. On a serverless database, min_connections: 0 is mandatory. One idle connection held open keeps the database awake 24/7 and can nearly double your usage at zero traffic. Never bake a platform's URL into a mobile app. Use a domain you own, so you can move servers without shipping a new app build. If you're new to this, don't worry — I explain every term below in plain language. Jargon, in one line each: Free tier = the no-cost plan, with usage caps. · Cold start / spin-down = a sleeping server takes a few seconds to wake. · Cron job = a task on a timer. · Connection pool = a small set of reusable database connections. · Serverless / scale-to-zero database = a database that sleeps when idle and bills by the second. · Compute Unit (CU) = Neon's unit of database processing time. · Hostname / subdomain = the address in a URL, like auth.notils.com . The setup I'm a solo developer. The stack is deliberately cheap: Three Rust backend services — a