I find personally that if there are libraries to help me out, I'm only slightly slower in Rust than I am in Ruby, but then there's no debugging time in Rust, and invariably, there will be tons of work I have to do later with the Ruby to shake out bugs.
YMMV.
Despite the fact that I chose to do this in Python, I'm not at all sure I wouldn't have had a working solution faster in a language that had a good type system and a error handling strategy that made errors explicit and forced them to be handled. I'm almost certain that writing in Rust would have ended up with something that was more reliable in the long term.
(FTR I imagine that Go may also have been a reasonable choice for this kind of work, but I haven't used it).