If you're deploying a REST API with authentication, caching and so on then the KISS solution is python with a framework (such as Django) in a docker container.

I've spent many many hours (years) trying nix, rust, Haskell, go, spring framework and all sorts of other things which are a lot of fun but not so good for getting shit done.

For other domains this doesn't apply of course; lower-level network stuff, portable CLIs, CPU-intensive workloads and so on are much better in go/rust but you can either integrate them with a network call, spawning an OS process or an FFI in the case of rust.