We tasked Opus 4.6 using agent teams to build a C Compiler
Nicholas Carlini from Anthropic's Safeguards team describes a research project utilizing 'agent teams'—multiple Claude instances working autonomously in parallel—to build a complex Rust-based C compiler from scratch. By employing a continuous loop harness and a Docker-based synchronization algorithm, 16 agents successfully generated a 100,000-line compiler capable of building the Linux 6.9 kernel for x86, ARM, and RISC-V architectures. The project, which cost approximately $20,000 in API fees, highlights structural strategies for long-running autonomous development, such as high-quality automated testing, role specialization, and specialized harnesses for managing parallel progress. While the experiment demonstrates a massive leap in LLM capabilities for 2026, Carlini also addresses the limitations of the current Claude 4 series and the security implications of deploying autonomous, unverified code.