Currently, we use gitolite the configure repository access permissions.
There it is possible to create hierarchies of repos.
We use products/* for actual products, components/* for shared submodules,
doc/, internal/, etc.
This is pretty handy when you need to deal with >100 repos.
Is there something comparable in Phabricator?
I could not find a way to organize repos, except maybe use a string prefix,
but this more a workaround.