Maddox built duckmath.org from his dorm, scaled it from 5K to 150K daily active users in 4 months, and sold it for $120,000. The wild part? The stack is dead simple: Cloudflare for hosting + domains + static DB (free) Supabase for backend, auth, user data ($20/mo) PostHog for analytics + A/B testing ($50K in free startup credits) Google AdSense for monetization (free) Repurpose.io to auto cross-post ($30/mo) React on the frontend, vibe-coded with AI Discord (7K members) for community He barely touched the code after AI hit. All the leverage went into volume: 3 TikTok accounts, 3 posts a day, 5 days a week.