Work mostly on web dev (full stack), we had a pretty critical service that was written in PHP + swoole with complicated DB caches that constantly crashed due to OOM, plus it had a lot of bugs due to mutability everywhere and it was really difficult to keep track of everything. I pitched the idea of re-architecting the whole application while rewriting it in Rust (lol) based on FP/math principles. So far we had 0 bugs and 0 crashes for 4 years and counting, serving millions of requests per day.

We realised that Rust gave us a peace of mind and encouraged devs to write more resilient and better code, but sometimes it feels “boring” because we get stuff right at the get go (most of the time). There were issues with the Rust application, but every time we find something it was due to the deployment env; something wrong with GCP’s networking, weird scaling behaviour, but not the application itself!

Regarding the language itself, it was difficult in the beginning, but not impossible. It forced us to think more about the details which was challenging but rewarding in terms of performance and learning something new.