Knock, knock. Race condition! Who's there? — A Refactoring Story

Knock, knock. Race condition! Who's there? — A Refactoring Story by Stefan Baumgartner. Concurrency in Rust can be hard, especially when the language throws other obstacles in your way. Like with this request that found me one day. What started as a humble ask to remove some indentation and nesting turned into a crime scene of concurrency gone wrong. Innocent memory being shared across tasks. A supervision task that made everything worse. A race condition waiting to strike. In this talk, we will apply refactoring techniques that address structure, ownership, and readability, while simultaneously making the actual problem visible. We'll solve the emerging concurrency problem by identifying what we actually want to accomplish, then turn everything upside down. In doing so, we'll rediscover proven patterns for async programming that predate async Rust but remain relevant today. About Stefan Baumgartner (he/him): Stefan Baumgartner is an architect and developer based in Austria. He is the author of "TypeScript in 50 Lessons" (Smashing Magazine, 2020) and "The TypeScript Cookbook" (O'Reilly, 2023). In his spare time, he organizes ScriptConf and Rust Linz. Stefan enjoys Italian food, Belgian beer, and British vinyl records. - bluesky: https://bsky.app/profile/deadparrot.dev - linkedin: https://www.linkedin.com/in/stefan-baumgartner-bb621564/ This talk was given at RustWeek 2026 as part of the Main track on Tuesday 19 May. You can find a playlist of all talks in this track at https://www.youtube.com/playlist?list=PL8Q1w7Ff68DCvQXADosMcF0aMvLhGXU4S, and a playlist of all RustWeek 2026 talks at https://www.youtube.com/playlist?list=PL8Q1w7Ff68DBpmF38rcIAf8Z9Gj2TnlgM For information about RustWeek 2027, go to https://2027.rustweek.org. We hope to see you there!

Refactoring in Rust

Stefan Baumgartner -- We refactor a Rust program that has just left the prototyping stage into code that is a delight to read and follow, easy to use, easy to maintain, and that plays along nicely with the ecosystem, all by learning Rust-specific refactoring techniques.

What it takes to keep Tokio running

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Most people don't see the work that goes into maintaining open source software. It's not just about writing code — it's also about reviewing PRs, helping new contributors, answering questions, fixing bugs, and writing documentation. In this talk, you will hear stories that explore the invisible work of open source software maintenance and discuss the challenges and rewards of this important work.

The currents of concurrency: reasoning with Async Rust

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Reasoning through concurrent systems has always been a challenging task. Poor code can be riddled with race conditions, non-terminating cases and other complex concurrency bugs; and even well-written code can be hard to understand. Async programming is an innovative concurrent programming model that rises to this challenge. In this talk, we'll explore reasoning with async Rust. We'll be introduced to its fundamental building blocks, such as `async`, `await`, `join` and `Pin`, and learn how to predict the behavior of code written with them. We'll build on these to simplify more complex concurrency puzzlers. Finally, we'll explore other models of concurrent programming to see how async Rust compares.