b4rruf3t.
The apps

minitrade

An options desk: live 24h tape, a TradingView-grade chart, a deterministic trade engine and a voice agent that reads it out loud.

python · langgraph · openai realtime · postgres

minibank

A neobank from first principles: double-entry ledger, sharded by customer, cross-region payments settled over Kafka with an outbox.

raw java 21 · postgres · kafka · no frameworks

minibroker

The bank's investment arm: portfolio, holdings and market prices on its own hostname, identity carried over from the bank.

raw java 21 · postgres · same ledger discipline

minimart

Four services, four databases, one storefront: catalogue, payments, analytics and logistics behind a single origin.

raw java 21 · postgres x4 · kafka

minipay

The payment service on its own hostname · the same ledger discipline, talking to the store only over HTTP and events.

raw java 21 · postgres · kafka

observatory

Agents you can watch think: the tool graph drawn live, every step and token traced while it runs.

langchain · langgraph · langsmith

options flow

The data engine behind the desk: a Rust collector writing dealer positioning into Postgres, minute by minute.

rust · postgres · node
The estate, as one system
level 0 · one box per service