Speaker
Abstract
Developing SDKs for your users in multiple languages can come at a high cost - especially if you need to implement complex logic client side, but traditionally options for sharing logic across those languages have been quite limited.
Rust provides a means of defining shared logic usable from multiple languages, much like you could with C, without having to… write C. Combined with an IDL for representation of shared objects, you have a powerful means to keep your language-specific layer thin.
In this presentation I’ll explain the architecture of Temporal’s open source SDKs, and how we use it to centralize some extremely complex logic across 5 user-facing SDKs written in different languages.
Topics will include:
- What Rust helps us with
- IDL choices and serialization concerns
- Asynchronous task representations across language boundaries
- Compiling to WebAssembly to avoid native extension issues
- Staying idiomatic in the host language
- Limitations and pitfalls
Interview
My session is about how devs who need to work in multiple languages can leverage Rust as a safe, modern, foundation for shared logic. Thereby keeping their language-specific layers thinner. This is by no means a new technique, but Rust provides a much safer and more convenient alternative to C.
The language landscape slowly, but inexorably, continues to expand. Developers expect to be met where they are, in their language of choice. The techniques in my talk allow library developers to more efficiently expand their coverage to additional languages than they could otherwise. Additionally, relatively recent technologies like WebAssembly unlock new and powerful alternatives to shipping native code, and Rust is at the forefront of that ecosystem.
Communicating between the native code and the language layer is nontrivial, especially when many languages are involved. Supporting a large matrix of operating systems and architectures can be a challenge, as can packaging and shipping the native extensions (for related reasons). I'll cover some techniques for solving these problems.
Immediately is a hard goal - but hopefully attendees will come away with some ideas for how they can either refactor an existing multi-language project to reduce its complexity, or a battle plan for any new project with such needs. They may also decide to familiarize themselves with Rust if they aren't already, which can be useful not only for the scenarios my talk covers, but possible usages of Rust beyond that.
QCon's long history stands out to me. It has a reliable reputation for delivering quality content, and avoids being overly marketing-heavy or trend-chasing. It appeals to senior engineers who are in search of genuinely deep technical content.
Topics
QCon San Francisco 2025 is a three day conference for senior software engineers, architects and team leads. An international program committee of working engineers selects every session. Patterns and practices, not products and pitches.
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