Each of these started as somebody's broken thing.

The interesting part

Most of it is boring CRUD done carefully. Two pieces are not. Cash and paper checks still dominate youth sports, so the app turns a photo of a check into a posted payment: the browser writes the PDF straight to cloud storage, a containerized service renders it to images, and a job engine in Postgres chains each step through a serverless route so no invocation outlives its 60-second cap. Lease-based serialization stops two workers from grabbing the same job.

The other piece is team formation. Sorting hundreds of kids into fair teams used to be a weekend of spreadsheets and hurt feelings, so I wrote a real solver: a greedy first pass, then simulated annealing against weighted hard rules and soft preferences. It balances grades, quarterback counts and how many kids come from each school, honors teammate-together and do-not-pair requests, keeps coaches near players they know, and makes sure every kid recognizes at least one face on their roster. It produces a few proposals with plain-English narration of the tradeoffs, and nothing goes live until a human accepts one.