On February 5, 2026, Nicholas Carlini from Anthropic published a piece about an experiment that runs significantly ahead of what most of us are doing with LLM agents today. Sixteen parallel instances of Claude Opus 4.6, two weeks of work, ~2,000 Claude Code sessions, a budget around $20,000. The output: 100,000 lines of a C compiler in Rust that builds Linux 6.9 on x86, ARM, and RISC-V; passes 99% of GCC's torture test suite; compiles PostgreSQL, SQLite, FFmpeg, Redis, and QEMU; and runs Doom. The repository is open and anyone can read it and try it themselves. It's serious engineering work, and the article itself is a great read for anyone thinking about autonomous agents in production. Carlini is honest about what worked and what didn't, walks through five concrete lessons from designing the harness, and shares numbers and metrics. This is exactly the kind of writeup the industry needs more of — a first-hand account of what long autonomous runs actually look like. Headlines split into two camps.…