lrt VS reflex

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.

Neat. I've used reflex in the past for this.

entr is written in C, watchexec is written in Rust.

There's another one that I've used that is written in go: https://github.com/cespare/reflex

I am inclined to use watchexec next time I need one.

rerun your go program when you change a file https://github.com/cespare/reflex

There are tools like https://github.com/cespare/reflex that run a command when specific files are changing. You could use it to run go test whenever one of your files changes, so the changes would be reflected instantly in the terminal.

We'll be using Reflex as part of our development workflow. If you're not familiar, Refelx provides live reload when developing.