Installing the Mux package is fairly simple. You need to run this command in the Terminal (Mac and Linux):

go get -u github.com/gorilla/mux

If you get any errors saying package github.com/gorilla/mux: cannot download, $GOPATH not set. For more details see--go help gopath, set the $GOPATH environment variable using the following command:

export GOPATH=~/go

As we discussed in the previous chapter, this says that all the packages and programs go into this directory. It has three folders: bin, pkg, and src. Now, add GOPATH to the PATH variable, to use the installed bin files as system utilities that have no ./executable style. Refer to the following command:

PATH="$GOPATH/bin:$PATH"

These settings stay until you turn off your machine. So, to make it a permanent change, add the preceding lines to your bash profile:

vi ~/.profile
(or)
vi ~/.zshrc 

Now, we are ready to go. Assuming Gorilla Mux is installed, proceed to the basics.