We run a medium sized trading system (20 microservices) in Deno for about a year now. There have been a few runtime quirks but they have currently all been ironed out. I love the approach that Deno takes with respect to permissions which allows you to strictly specify which urls your program can access, which files/directories can be read/written, etc.
You are most likely aware but just to point out, Node now also has a version of the permissions features [0] (not sure on parity but it was obviously deno inspired) behind an experimental flag!
