#Overview

A personal finance tool for recording income and expenses, categorising transactions, and watching spending trends develop over time. Next.js on the front, Supabase handling auth and Postgres behind it, so each account's records stay isolated at the database layer rather than depending on the application to remember to filter. Deployed on Vercel.

#Building With Claude

Claude did the scaffolding, the schema, and the Supabase row-level security policies. That last part is the reason this is worth writing down: RLS is the layer of a Supabase app most likely to be quietly wrong, because a policy that is too permissive fails silently and looks identical to one that works. Having a second reader interrogate every policy — what does this allow that I did not intend? — costs almost nothing, and it is exactly the review a side project would otherwise never get.

The speed was not the interesting part. The interesting part was that the boring, high-risk layer ended up with more scrutiny than the fun one.