Notes
Engineering write-ups
Short, specific notes from building voice and agent systems — not tutorials, just what the work actually taught.
Measure latency where the user feels it
A client-side timer measures something real, but the number that predicts how a conversation feels is endpoint-detected-to-first-audible-token, measured on the server.
A payment webhook will fire twice
Payment providers retry webhook delivery on any ambiguous response — the idempotency key has to be there from the first handler written.
A working local demo says nothing about the network path
Localhost tells you the application logic is sound. It tells you nothing about NAT traversal, TURN relay cost, or mobile network jitter.
An unscored prompt change is a guess
Eyeballing three example outputs is not measurement — it is a guess wearing the clothes of an experiment.
Free resources