typesafe-rs

Latency-focused community Rust SDK for System One with official-SDK parity, an optional blocking client and an in-process mock crate.

LibrarybetaMIT

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Overview

typesafe-rs is an MIT-licensed community Rust client for TypeSafe's System One API. Environment variables, defaults, retries, identification headers and error kinds match the official Python SDK and @typesafe-ai/sdk. It is async by default on tokio, with an optional blocking feature, and uses rustls TLS by default with native-tls available. MSRV is Rust 1.85.

Questions are built with a questions! macro and fluent builders (when_true and when_false for Noul criteria, option for Choice, level for Score), and responses offer typed accessors. A companion crate, typesafe-rs-mock, provides an in-process mock of /v1/systemone and /v1/models for tests. The lists describe it as latency-first. It is published on crates.io with CI. The README states that environment variables, defaults, retries, identification headers and error kinds were matched to the official SDKs on purpose.

What the decision model decides

Type	Question	Answers
Yes / no	Does this convey urgency?	Explicitly time-sensitive · No time pressure
Choice	Which team should handle this?	billing · technical · sales
Score	How frustrated is the customer?	Calm · Frustrated · Very angry

How it works

Add typesafe-rs (and tokio) to Cargo.toml.
Create a Client from the environment.
Call system_one with state and the questions! macro.
Read noul, choice or score from the response.

Strengths

Behavior parity with official SDKs.
In-process mock crate for tests.
Async or blocking clients.

Caveats

Community SDK; version 0.1.
Requires a TypeSafe key.

Getting started

Add typesafe-rs = "0.1" to Cargo.toml and export TYPESAFE_API_KEY.

At a glance

Type: Library
Status: beta
Language: Rust
Runtime: library (crate)
Has code: yes
Has tests: yes
License: MIT

Use cases and integrations

Infra / SDKs / Integrations537

SDKs and API clients331

How curated lists describe it

Latency-focused Rust transport SDK aiming for behavioral parity with the official clients.
AnotiaWang/awesome-decision-models
A community Rust Jev client with async requests, an optional blocking interface and local mock testing.
logicrw/awesome-jev-projects
Latency-first Rust SDK for TypeSafe System One.
hellogumbo/awesome-jev

Frequently asked questions

How do I test without the API?

Use the typesafe-rs-mock crate, which mocks the endpoints in-process.

Is there a blocking client?

Yes, behind the blocking feature.

What is the minimum Rust version?

1.85.

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