Rust Forge 2025

2025-09-02

I normally don't write about the conferences I go here, but Rust Forge is different for two reasons: (1) I had the pleasure to give my first talk in English there, and (2) the conference really felt like a place to share ideas and not necessarily consume content.

Let me focus for now on the conference. The first two days were "co-creation days" with a bunch of (technical) workshops and some tours around Wellington (NZ). It was a great opportunity to bound with different people over the activities. We visited Zealandia at night, and some people were able to see Kiwis (not me :C).

During a dinner, I was lucky enough to sit with amazing people and learn so much from the conversation. I learnt some details about Rust Incremental Compilation. How a "push-based" approach could speed up things (more similar to Zig approach) and that sometimes the rustc may do some work and throw the result away later, because it was not needed. I also learnt about wild linker (btw, amazing talk during the conf about it by David!) and zngur (tool for C++/Rust interop).

The talks were about Rust in embedded, passing by linkers, cargo-semver-checks to community and governance.

A lot of the talks were made by the local community which made everything even more fun!

I also gave a talk there about Rust testing. It was my first time speaking in a conference in English, the last time I talked in a conf was during FliSol in 2013, back in Brazil!

My talk was mainly about how the Hyrum's Law makes any re-write much harder than we can think of, because we have to keep any observable behaviour, which may be hidden away in some abstraction / lib we used and won't be able to use it anymore. Of course, we can use tests to help us: "replaying production traffic", table-driven tests and shadow envs. That is what I tried to show with a real world example.

I almost forgot about the food, Tim prepared for us a lot of snacks and food during the breaks. All of it was vegetarian or vegan, which really made my life (as a vegan) much nicer. Normally the vegan food is just an after-thought, but during Rust Forge it was one of the main options!

I hope there is a Rust Forge next year, and for that to happen more companies need to step up and help financially...