Sure, I think it'd be a fun project to try! We use Rust for compiler construction, obviously, and it works great for us. Bear in mind, though, that Rust is manually memory managed, and there is significant cognitive overhead of having a compiler that checks that you're doing the manual memory management properly as opposed to just using a GC.

I think if you want a really fast symbolic evaluation checker—say, the kind that you're going to run on $BIG_COMPANY's codebase on every checkin—Rust would be a really good fit, because you get pattern matching and excellent performance. Other than OCaml and (maybe?) F#, I don't know of a language that has as sophisticated a pattern matcher as Rust does, which helps a lot with this stuff. But, if you're building a one-off tool, a more dynamic language with a GC might be more convenient.

Would it be likely that I could get around that problem just by using arena allocation? Do you think the allocation patterns of a symbolic checker fit that sort of "just allocate everything and forget about it, then free it all at once" pattern? Does Rust make it easy to punt that way?

Yup, you can use arenas for that, and in fact that is likely what I'd do. There's an arena crate on crates.io. https://crates.io/crates/typed-arena/1.0.1

F# has Active Patterns, which really rock. They let you define custom patterns or destructuring functions, then use them like normal patterns.

https://msdn.microsoft.com/en-us/library/dd233248.aspx

Okay, an off-topic question: Can you pls briefly explain Golang-emulators-fit? Links to projects/blogs would help too. Thx.