TL;DR: Fern now supports Rust. Generate production-ready Rust client libraries from your API spec, built for performance-critical applications.
Bringing Rust support to Fern
Rust developers have been asking us for native SDK support, and now we've delivered.
For teams building high-performance systems, Rust is often the language of choice. But maintaining a hand-written Rust SDK is time-consuming. Fern automates this process, generating a type-safe client that integrates seamlessly with your API while eliminating the need to write and maintain serialization, networking, and error handling code.
Code that looks and feels native to Rust
When building our Rust generator, we looked at widely adopted Rust SDKs — including AWS's Rust SDK — to understand what production-grade client libraries look like. We adopted the builder pattern for constructing requests and other principles that make these libraries feel native.
AWS's SDK is handcrafted around the Smithy modeling system, while Fern generates the same ergonomic patterns directly from your OpenAPI or AsyncAPI — keeping your SDK automatically aligned with your API as it evolves. The result is a client that feels at home in modern Rust codebases without requiring a dedicated team to maintain it.
Key features of Fern's Rust SDK:
- Full async/await support throughout
- Native streaming capabilities for real-time data
- Strongly-typed request and response models with
serde - Wire tests verify generated code matches your spec
- Type-safe error handling with
Resulttypes - Minimal dependencies
The generated SDK integrates naturally into existing Rust projects without feeling machine-generated.
One-command publishing to crates.io
When your API evolves, Fern regenerates and publishes an updated SDK to crates.io in a single command. Developers add your SDK to their Cargo.toml, Cargo fetches it, and they're ready to make API calls. No friction, no manual maintenance.
First customer: Payabli
Payabli, a payments infrastructure platform, was our first production customer for Rust. They use Fern to generate and maintain their Rust SDK.
Getting set up with the Rust SDK was genuinely a breath of fresh air. I ran like three commands, and then I could use our API with all of the thoughtful additions that Fern adds into their generated SDKs: amazing types, great generated references, an idiomatic and language-native feel, and the confidence of not relying on umpteen third-party libraries. As a result, writing docs to get set up with our new Rust SDK was pure joy.
-Elijah Skeirik, Technical Writer at Payabli
Get started with Rust
Interested in shipping a Rust SDK? Contact us or jump straight into the Rust quickstart guide.
FAQs
1. What is a Rust SDK and why do I need one?
A Rust SDK is a prebuilt client library that lets developers integrate with your API faster. Instead of writing networking and serialization logic from scratch, developers can import the SDK and immediately call your API with type-safe, idiomatic Rust code. Rust SDKs are especially valuable for performance-critical applications.
2. Does the Fern Rust SDK support async/await?
Yes. The SDK uses modern async/await patterns throughout, so your API calls integrate seamlessly with Rust's async ecosystem.
3. What makes Fern's Rust SDK different from other code generators?
Fern's Rust SDKs are designed to feel handwritten. We generate idiomatic Rust code with strong typing, minimal dependencies, and wire tests to verify correctness. Our SDKs are built for performance-critical applications where Rust shines.
4. What programming languages does Fern support?
The Fern SDK generator outputs client libraries in TypeScript, Python, Java (Kotlin-compatible), Go, Ruby, C# (.NET), PHP, Swift (iOS), and Rust.
5. What API specifications does Fern support?
The Fern SDK generator supports OpenAPI (versions 2.x and 3.x), AsyncAPI (3.x), and gRPC/Protobuf.
6. How do I get started with Fern's Rust SDK generator?
Get started with the Rust quickstart. First, install the Fern CLI and point it at your API specification (OpenAPI, AsyncAPI, or gRPC). With a single command, Fern generates a production-ready Rust SDK that you can publish to crates.io. From there, developers can add your SDK to their Cargo.toml and start making type-safe API calls with async/await.
