Microsoft nine engineers merge 1,211 Copilot Cowork pull requests

A small Microsoft engineering team built Copilot Cowork, an agentic execution layer for knowledge workers, from an empty repository to worldwide general availability in about four and a half months. Using AI agents to write most of the code, the team developed six core practices—including strict markdown specifications, narrow agent boundaries, rigorous automated checks, and moving live runtimes from Python to Rust—to scale development up to over a thousand pull requests a day. Open article →