system design
Beyond CRUD.
The endpoints work. Then come the queues, the databases under load, the cache that goes stale, the retries, the outages and now the AI calls. Essays go deep on one of these. Notes are shorter, one gotcha and the code.
- 21 Oct 2026note
One word keeps your table writable while an index builds
CREATE INDEX vs CREATE INDEX CONCURRENTLY in Postgres, and the four things that bite people when they switch.
#postgres#migrations2 min→ - 20 Oct 2026note
An AI agent just got a 503 from your API
A human gives up after two refreshes. An agent doesn't. Four things I'd ship on any API that agents will call.
#api-design#ai-agents#reliability2 min→ - 29 Jul 2026essay
How Dead Letter Exchanges Prevent Distributed Systems From Silently Failing
One bad payment event can keep thousands of healthy events waiting. The interesting part is not what a DLX is - it is deciding which failures should leave the hot path, and what happens after they do.
#rabbitmq#queues#reliability13 min→