Anthropic details how it used 16 parallel Claude Opus 4.6 agents to build a Rust-based 100,000-line C compiler, incurring ~$20K in API costs over 2,000 sessions (Anthropic)

Anthropic: Anthropic details how it used 16 parallel Claude Opus 4.6 agents to build a Rust-based 100,000-line C compiler, incurring ~$20K in API costs over 2,000 sessions   —  We tasked Opus 4.6 using agent teams to build a C Compiler, and then (mostly) walked away.  Here's what it taught us about the future of autonomous software development.