I started working with Rust last month, and wrote about 2000 LOC since then. While I had my fair share of errors coming from the borrow checker, I've always found its complaints to be valid and easily resolved. Except for that one time where I tried to shuffle data between different threads and shouted at the borrow checker for two hours, until I realized that the borrow checker was actually right and what I tried to do was literally impossible without data races.

Were you writing functions/procedures under the implicit assumption that they would be executed under a single threaded context? Because Rust does not allow this assumption without using "unsafe". I've run into this before, and it can be a bit irritating, but if there's even a small chance you'll later want to execute the code in a multithreaded context, it will more than pay for the inconvenience. And if you're sure you won't, then you can just throw the data into an UnsafeCell and call it a day.

It's not even inherently about multi-threading https://manishearth.github.io/blog/2015/05/17/the-problem-wi...