Writing
One essay per system, plus an overview of why I built four build-your-own-X backends instead of CRUD clones. Every one of them has a live demo you can break — the essay explains the mechanism, the demo proves it runs.
- 2026-06-20
Four systems, and what each one proves
Why I built four build-your-own-X backends instead of CRUD clones — and the one hard thing each one is meant to prove.
- 2026-06-20 · Concurrency
Zero oversold seats under 1,000 concurrent bookings
A two-layer no-double-book design — a Redis hold in front of a Postgres conditional write — plus a Kafka outbox, and a stampede that proves it never oversells.
- 2026-06-20 · Distributed systems
A Raft KV store you can kill, partition, and watch recover
A from-scratch Raft implementation — leader election, log replication, the §5.4 safety rules — running five nodes over a transport you can break in the browser.
- 2026-06-20 · Real-time
A real-time multiplayer canvas: a grow-only CRDT and Lamport ordering
Conflict-free convergence across clients and server instances — a grow-only-set CRDT, Lamport ordering, Redis fan-out — with 701 real messages relayed.
- 2026-06-20 · AI infrastructure
An OpenAI-compatible LLM gateway: routing, caching, and a circuit breaker
A drop-in multi-provider proxy that keeps serving when a provider falls over — model routing, response cache, SSE passthrough, and a per-provider circuit breaker.