“To illustrate that, I'm going to walk through a control loop that we use internally at HumanLayer. For our loop, we are incrementally migrating our RPC API to Effect. We adopted it for some of our race prone code. We like it, so we're adopting it across the rest of our code base.”
Context. Mistele introduces the worked example he uses for the rest of the talk: a daily agent loop at HumanLayer that migrates RPC procedures to the Effect library.
Kyle Mistele, Co-founder, HumanLayer. A founder of a company that builds with coding agents every day and runs the migration loop he describes; HumanLayer sells AI coding tooling, so the talk also promotes its approach.
HumanLayer sells AI or agent tools or services, so it has a reason to publish flattering numbers about AI. The passage stays in the archive; read it with that in mind.
How this was checked
Checked against the source by a first reader, then confirmed independently by a second reader who fetched the source without seeing the first reader's notes (Independent review agent (Claude Sonnet), blind second pass from passage text and citation only, no repository access, 2026-11-03).
Whisper reads 'we are incrementally migrating our RPC API to effect… across the rest of our code base.' The difference from the passage is whisper's lowercase 'human layer' and 'effect' vs 'HumanLayer' and 'Effect' (proper nouns).
How to cite this passage
Kyle Mistele (HumanLayer), “Loop Engineering from first principles”, AI Engineer (YouTube), 2026-07-25, at 9:09. https://www.youtube.com/watch?v=xIt_mTQp6mY Archived at https://the-ai-record.com/passages/humanlayer-migrating-rpc-api-to-effect-loop-2026
Context. Mistele has just described scheduling the migration loop to run once a day as a CI workflow, and goes on to the problem HumanLayer hit with the first version.
Context. Mistele is opening the part of his talk about how his company builds agent loops, after arguing that loops which produce unreadable pull requests are the wrong design.
HumanLayer