How is Rust in terms of incremental compile time? Is incrementally recompiling on file in a large project quick? Hopefully link times aren't that bad.
One thing I like about the JVM is hot code reloading. Most of the time, changes inside a method/function takes effect immediately with hot code reloading.
Link times are the worst part but solveable with mold[1]/sold. Incremental compilations are usually an order of magnitude (or even two) faster than clean compiles but tbh that can still feel slow. Helped by using something like sccache[2] or even cranelift[3] when debugging. Still not as fast as having a hot-reloadable language but it gets you to a relatively pleasant speed still IME
I've never been successful in getting sccache to really speed up projects, but then again only release builds have _really_ been impossible for me, and that's only when I was working on Deno which was absolutely massive.
We had issues with long compile times at deno. Release builds were brutal, debug builds were OK as long as they were incremental. It was likely one of the largest open-source rust applications, but we were still quite productive.
Most likely you'll have years before it's an issue and there are mitigations.