gopickgo

gopickgo picks the "right" go (or gofmt) binary based on your current directory, so you don't have to think about which Go version to use.

Search order

Project-local toolchain: walks up from the current directory looking for a go.mod, then tries ./tool/go relative to the module root (or ../bin/go if you're inside the Go source tree itself).
$HOME/sdk/go: a bare ~/sdk/go directory, if present.
Highest versioned SDK: globs ~/sdk/go*, parses the version suffixes, and picks the highest semver (e.g. ~/sdk/go1.23.4 over ~/sdk/go1.22).
System Go: /usr/local/go/bin/go, /usr/local/bin/go, /usr/bin/go.

The first candidate that exists on disk wins.

go install github.com/bradfitz/gopickgo@latest

Then symlink go and gofmt to gopickgo somewhere early in your $PATH:

ln -sf $(which gopickgo) ~/bin/go
ln -sf $(which gopickgo) ~/bin/gofmt

Make sure ~/bin (or wherever you put the symlinks) appears in your $PATH before /usr/local/go/bin or /usr/bin.

When invoked as gofmt, gopickgo finds the right go, resolves its GOTOOLDIR, and execs the corresponding gofmt.

To see which go binary gopickgo would pick:

gopickgo pick

or equivalently (if you've symlinked go to gopickgo):

go pick