I Built a Complete SaaS in 45 Minutes Using Only AI + One API

I want to be upfront: the "45 minutes" doesn't include the three hours I spent the night before trying to do the same thing with separate API accounts and giving up because I couldn't get OAuth to work with my Cloudflare Workers setup. The 45-minute version happened the next morning after I said "screw it" and tried doing everything through one gateway. It worked. I was annoyed it was that easy, because it meant the previous night was wasted. Here's the actual build. What I made InvoiceBot — a dead-simple SaaS: Sign up with Google Type a description like "3 pages of web design at $500 each" AI generates a professional invoice Send it to your client via email Pro plan for $9/month via Stripe Not going to win any awards. But it has auth, payments, a database, AI generation, and email delivery. That's a real SaaS, not a landing page. The stack Claude Code (my coding agent) SkillBoss (everything backend: AI, database, auth, email, payments, hosting) That's it. No AWS. No Vercel. No Firebas