Auto-Arch Tournament vs Claw Code

Auto-Arch Tournament is an autonomous research system where an AI agent iteratively proposes, implements, and validates microarchitectural improvements to a RISC-V CPU. Starting from a standard 5-stage pipeline, the loop runs hypotheses in parallel, each going through formal verification (53 symbolic checks), cycle-accurate simulation, multi-seed FPGA place-and-route, and CoreMark CRC validation. Only hypotheses that beat the current champion get merged; everything else gets discarded. Starting from 301 iterations/second, the system hit 577 iter/s (+92%) across 73 attempts in 9.8 hours — producing a design 26% faster and 40% smaller in LUTs than the baseline. The insight the author drives home is that the real innovation isn't the AI agent — it's the verifier. The orchestrator is hardcoded to prevent agents from manipulating their own evaluation gates, a simple but critical design constraint that turns a creative process into a trustworthy one. Without a rigorous verification harness, agent-driven optimization becomes a confidence trick. This is early but fascinating proof that AI-driven hardware design loops can produce commercially meaningful gains. The repo uses Claude Code or Codex as the coding agent, SystemVerilog for the RTL, and standard open-source EDA tooling (Yosys, nextpnr, Verilator). It's a compelling template for anyone building agentic optimization loops where correctness matters.

Claw Code is an open-source AI coding agent framework built by Sigrid Jin as a clean-room rewrite of Claude Code's agent harness architecture — written from scratch in Python and Rust without copying any proprietary code. Released April 2, 2026 in response to the March 2026 Claude Code source leak, the project accumulated 72,000 GitHub stars within days of going public, signaling enormous pent-up demand for an inspectable, extensible, subscription-free alternative. The architecture splits cleanly by responsibility: Python (27% of codebase) handles agent orchestration and LLM integration, while Rust (73%) powers performance-critical runtime execution. Developers get 19 built-in permission-gated tools, 15 slash commands, a query engine for LLM API management, session persistence with memory compaction, and full MCP integration for external tools. Crucially, Claw Code supports Claude, OpenAI, and local models interchangeably — you're not locked into any provider. Unlike Claude Code's $20/month subscription, Claw Code is MIT licensed and completely free. The trade-off is that you supply your own API keys and manage your own infrastructure. For developers who want the power of an agentic terminal coding workflow without the proprietary lock-in, Claw Code is the most architecturally serious option yet to emerge from the open-source community.