# sys1 sys1 is an open-source inference server written in [[Rust]] by Alvaro Bartolome. It serves open-weight [[System One Models|System One models]] behind an API that copies [[TypeSafe AI]]'s: you send the same request you'd send to [[Jev]] (a state plus typed questions) and get typed answers with probabilities back. Except it runs on YOUR machine. Why does that matter? Because the main objection to Jev is that it's a closed API you have to send your data to. sys1 keeps the interface and swaps the model for an open one, so code written against Jev can point at a local endpoint instead. What it does: - **TypeSafe-compatible endpoint.** `POST /v1/systemone` (alias `/v1/decide`), with the same three question types: `choice`, `score` and `noul` (see [[System One Primitives]]) - **Open models only.** Today that means [[Laya]]: `convaiinnovations/laya` (English, guardrails, email triage), `laya-multilingual` (100+ languages, ~2.2x faster) and `laya-typed-decisions` - **Built for speed.** Tokio, axum and serde for the server, Hugging Face's candle for inference, dynamic token-based batching, SDPA on CPU, Metal and CUDA, and Flash Attention 2/3 on Ampere, Ada Lovelace and Hopper GPUs - **Easy install.** `cargo install sys1 --features cpu` (or `metal`, `cuda`), then `sys1 --model-id convaiinnovations/laya --dtype auto` The example in the README is a good one: a "charged twice, refund me today" support message, with a Choice for the route (billing, bug, account), a Score for urgency on a four-level rubric, and a Noul for "escalate to a human?". Three decisions, one request, no text generated. Keep in mind that sys1 is a server, not a model. Its answers are only as good as the open model behind it, and Laya isn't Jev: it hasn't been trained with [[Reinforcement Learning for Calibrated Decisions (RLCD)|RLCD]], so don't assume its probabilities are calibrated the same way. Measure on your own data first. I like it because it makes the TypeSafe API shape a de facto standard, like the OpenAI chat API before it. Once several servers speak the same format, you can prototype on hosted Jev and move sensitive workloads to a local box without rewriting anything. [[OpenClaw]] already took that route with a provider-neutral decision model setting. ## References - [sys1 on GitHub](https://github.com/alvarobartt/sys1) - [Laya](https://laya.convaiinnovations.com/) ## Related - [[Jev]] - [[Laya]] - [[System One Models]] - [[System One Primitives]] - [[Kev]] - [[SemIf]] - [[TypeSafe AI]] - [[Rust]]