Introducing Git fastclone
corner.squareup.com
corner.squareup.com
There's also `mr` - multirepo from Joey Hess,the creator of git annex'
https://github.com/orrc/git-webhook-proxy https://www.cloudbees.com/blog/advanced-git-jenkins
worktree appears to do away with the extra complication; it's just another working tree off the same base clone. There's a single object store. You have two commands to deal with, 'git clone' and 'git worktree'.
I think that both can be used for the same purposes and yield similar results, but fastclone is targeted at the automated build scenario whereas worktree is more developer-focused. In an automated build environment with an m:n relationship between repos and builds, I think worktree would be more complicated because you'd have to handle the 'clone vs. worktree' decision yourself. It's also apparently not great w/ submodules yet; fastclone claims to handle submodules.
Fastclone is another attempt to deal with the distributed-ness of git in a scenario where you don't want or need local copies of the objects, just the working tree. We fight with this at my company; we like git, and it does some nice things, but our use case is really better suited to a centralized vcs. For people looking at fastclone, etc. - consider that maybe you don't really want a dvcs in the first place.