go-clone

5 years earlier, gohack was written for the same reasons this tool was written. gohack has a good justification for this kind of tool so here it is:

Gohack: mutable checkouts of Go module dependencies

The new Go module system is awesome. It ensures repeatable, deterministic builds of Go code. External module code is cached locally in a read-only directory, which is great for reproducibility. But if you're used to the global mutable namespace that is $GOPATH, there's an obvious question: what if I'm hacking on my program and I want to change one of those external modules?

You might want to put a sneaky log.Printf statement to find out how some internal data structure works, or perhaps try out a bug fix to see if it solves your latest problem. But since all those external modules are in read-only directories, it's hard to change them. And you really don't want to change them anyway, because that will break the integrity checking that the Go tool does when building.

Luckily the modules system provides a way around this: you can add a replace statement to the go.mod file which substitutes the contents of a directory holding a module for the readonly cached copy. You can of course do this manually, but gohack aims to make this process pain-free.

Install go-glone

go install go.wit.com/apps/go-clone@latest

go-glone itself

This will make a work directory and download everything needs to compile go-clone.

go-clone --work go.wit.com/apps/go-clone