VLM Evaluation
Claude, chessboards, and spatial reasoning
A small chessboard-to-FEN experiment showed where Claude vision struggles: not global understanding, but exact square-level localization.
Engineering / Field Notes
Field Notes
Short technical notes, links, lessons, and observations from production work.
all notes
Operations
Reuse HTTP connections in Python services
A short field note on replacing repeated bare requests calls with a shared session so Python services can reuse HTTP connections.
Frontend Performance
One CORS header that removed hundreds of milliseconds from repeated API calls
A practical note on preflight caching, custom auth headers, and why OPTIONS requests quietly dominate app latency on slower connections.
Operations
A Postgres backup is not real until you restore it
A field note from a simple offline Postgres migration: why pg_dump was enough, where read-only mode fits, and why the restore drill matters more than the dump command.
Media Infra
The hidden 6 MB Lambda trap: compression after the limit is too late
Why API Gateway compression can make large responses look safe in testing, then still fail when Lambda enforces the raw payload limit first.
Build Systems
How we made Python ML containers smaller and faster to deploy
Slim bases, same-layer cleanup, CPU-only PyTorch, pinned wheels, and the unglamorous work of keeping deploys fast.