How to Use Multiple Go Versions on the Same Machine

Install multiple Go versions using the `go install golang.org/dl/go<version>` command and switch between them by updating your PATH and GOROOT environment variables.

Use the go install golang.org/dl/go<version>@latest command to install specific Go versions, then switch between them using go version and go install.

# Install Go 1.21 and Go 1.23
go install golang.org/dl/go1.21@latest
go install golang.org/dl/go1.23@latest

# Switch to Go 1.21
go1.21 download
export GOROOT=$(go1.21 env GOROOT)
export PATH=$GOROOT/bin:$PATH

# Verify the active version
go version

Alternatively, set the GODEBUG environment variable to control runtime behavior for specific versions without changing the toolchain:

export GODEBUG=http2client=0,panicnil=1
go run main.go

You can install multiple versions of Go side-by-side on your machine, similar to having different versions of a web browser installed. You switch between them by telling your computer which one to use for the current task. This lets you test old code with old tools or new code with new tools without conflicts.