How I prevent double bookings in Postgres (advisory locks + Supabase)

I built a booking app for gyms with React, TanStack Start and Supabase. The part that looked easy and wasn't: two people booking the same slot at the same moment. This post explains the approach I ended up with, with a simplified version of the code. The problem A client opens the booking page, picks a service, a date and a time slot. Two clients... Weiterlesen: How I prevent double bookings in Postgres (advisory locks + Supabase)