Building a Production-Ready Auth System: How I Shipped a Complete MVP Foundation in One Day
Today, I shipped the authentication foundation for HandyFEM—a marketplace app for women in the skilled trades. What started as a scaffolded Next.js project became a fully-tested, security-audited auth system with database migrations, login/signup flows, and a verified access control layer. Here's how I did it (and what I'd do differently).
I have to admit that I was lucky enough that at the point of starting with this, the new Anthropic Claude model Fable 5 was released and set for free for some time! The first thing I did was run a prompt on the base of all my project for it to review it and find improvements... which it did!
The Starting Point
I had a design system and a blank canvas. The scope seemed straightforward on paper: wire up Supabase, build login/signup screens, add some database tables. In reality, "straightforward" auth is where most apps spring security leaks and user experience disasters.
