Engineering notes
Thinking in public, one decision at a time.
Short, practical notes from building backend-heavy products and applied AI systems.
01SCRIBE · 5 min readBuilding RAG That Can Say ‘I Don’t Know’Why retrieval quality, evidence thresholds, and abstention matter more than a polished chat response.02Ledgerly · 4 min readTenant Isolation Beyond a userId FilterLayering application checks with PostgreSQL row-level security in a finance system.03PingMe · 4 min readDesigning Ephemeral Chat with Redis TTLHow an expiry-first data model changes room state, cleanup, and the promise made to users.