Create an empty directory, download the code and run it:
$ mkdir /tmp/lj
$ cd /tmp/lj
$ wget https://gist.github.com/benbjohnson/5622779/raw/e53d227ebdbea8d513b62ad076feb3f6ac1c1594/luajit.go
$ go run luajit.go
And you should see:
Hello from the C preamble!
Hello from Lua!
Hello from the C preamble!