[cirwin]

To do this well (for servers, which is the most common case) you need to keep the port open (and delay requests while recompilation is in progress) or clients can see transient errors. So it's probably not a language level concern, but a protocol level one (it's very solvable for HTTP for example).

I built https://github.com/superhuman/lrt which tries to solve this problem in a go-like way (no configuration required, minimal log noise, and reliability/simplicity as the primary design goals) for Superhuman.