Alan is an open source project and for many years source has been available, during the last decade on Bitbucket. For various reasons GitHub has become a more and more apropriate site for hosting open source projects. There has also been some activity there to consolidate some Alan related project into an organization not surprisingly called alan-if, primarily thanks to Tristano Ajmone. One of the most important is the alan-docs project, where you can find many of the Alan documentation projects. So Alan has moved there too.
I hope this will make Alan even more visible, and make it easier to cooperate on improving the Alan system.
(The old repo on Bitbucket, will still exist, but only rarely be brought up to date.)