As always I did a half-arsed read of the instructions, just forked the github repository then made a lokal clone.
Ξ /srv/http → git clone [email protected]:greenwellness/spree.git
Cloning into 'spree'...
Warning: Permanently added the RSA host key for IP address 'xxx.xxx.xxx.xxx' to the list of known hosts.
remote: Reusing existing pack: 157334, done.