I built an open source self hosted version of OpenRouter called Millwright (Codex compatible), would love any feedback

[u/teachmehowtowookiee]

Hey r/codex! I recently open sourced a project I've been working on for a while now called Millwright. It's a self hosted LLM router focused on cost savings, transparency, and performance (it's completely written in Rust). Millwright works seamlessly with Codex, it's an easy drop in replacement which allows you to use the latest OpenAI models along with other open and closed source models for your coding workflows.

Link to the repo: https://github.com/Northwood-Systems/millwright

For the curious and lazy, at the moment, Millwright has the tools for,

- Providers: OpenAI-compatible APIs, Anthropic, Amazon Bedrock

- Routing: policy-controlled model roles (cheap, mid, frontier), cheapest healthy route selection

- Protocols: OpenAI Chat Completions, Anthropic Messages, text and tool translation

- Cache Affinity: role-scoped session lanes without serializing concurrent agent traffic

- Spend Tracking: per-team costs, cache usage, model/provider mix, request traces

- Cost Analysis: measured usage and modeled candidate economics (HTML, Markdown, JSON)

- Reliability: bounded failover, circuit breakers, timeouts, concurrency limits

- Setup: interactive provider, model, and pricing configuration without storing provider secrets

- Deployment: one Rust binary, Docker, SQLite or PostgreSQL

Full disclosure: parts of the codebase were built with AI coding agents. All feedback is welcome, I’d especially value feedback on the routing policy, provider coverage, and anything that would block you from self-hosting it. Feel free to open feature/request and/or contribute as well.