A microscope for Tokio and Rust applications Zola 2026-05-30T00:00:00+00:00 https://dial9-rs.github.io/atom.xml 2026-05-30T00:00:00+00:00 2026-05-30T00:00:00+00:00 Russell Cohen https://dial9-rs.github.io/blog/3-bugs-that-arent-in-dial9/

<p><a href="https://github.com/dial9-rs/dial9">dial9</a> is a microscope for Tokio (and Rust applications in general): its compact binary format can record a log of runtime events so you can reconstruct what actually happened to understand bugs and performance behavior. It runs in production, where bugs have real blast radius.</p> <p>As much as we attempt to avoid it, dial9 still has bugs. We catch most in CI, some in PR review, and some are discovered by customers.</p> <p>We use AI to help build dial9, but this presents a challenge: today's models are jagged: strong in one domain, weak in another. Folks are probably familiar with "<em>How many r's are in Strawberry</em>" or "<em>I want to wash my car, the car wash is 50m away. Should I walk or drive?</em>" These are real but don't really capture what this looks like in practice. Here are three examples we hit building dial9.</p>