Tutorials

Notes from building the templates.

Step-by-step guides on Flutter, Compose and shipping to the stores. Written while solving the problem, not after.

All Multi-vendor delivery Flutter Jetpack Compose Kotlin Next.js Monetization / AdMob Browse by topic →

Double-Booking in Postgres: The Availability Check Is Not a Reservation

Two taps in the same second sell the same room twice, and it never reproduces on your machine. A range column, the constraint that refuses the overlap, the error code to catch, and what happens to a hold nobody pays for.

8 Sep 2026 · 13 min

Next.js

Building an Admin Panel for Your Mobile App with Next.js and Supabase

Row-level security, a typed client, and a dashboard you can hand to a non-developer — plus the one key that must never reach the browser.

11 Aug 2026 · 15 min