He left Meta to build a $30K/month golf app. Here’s his entire tech stack: Next.js on the frontend Google Firebase as the backend That’s it. No exotic infra, no 10-person team. Just a senior engineer scratching his own itch at a local golf course, shipping nights and weekends until 150 courses were paying him. Now at $350K ARR and pacing to $800K, he finally quit Meta to go all in. The lesson: the stack isn’t the moat. Building something you’d do for free is.