Amazing write up! Everyone at work is itching to try Rust, but I think what’s killing adoption is that it’s not very clear how to gradually transition a code base. We have a few million lines of C++, some of it written 25 years ago. A full rewrite is just out of the question, at best we could use it for new sections. This is super common in the c++ world, so it’s a pity that porting wasn’t a first class concern in rust considering C++ devs are the target audience. It sounds like it was a challenge even at 57k LOC. Congrats to the fish team though, great accomplishment!