Atlas v0.10.1 shipped with Nim 2.2.8. It has some great improvements.
This means Atlas no longer clones unused historical dependencies!
All transitive dependencies (i.e. indirect deps) are treated as lazy dependencies by default. SAT runs on the initial dependency graph and solves for an initial solution. If any requirements are lazily loaded dependencies, they're cloned and SAT is re-run to find the final solution. This iterates until a full solution is found and all required deps are cloned. For details see solver.md.
The flag --no-lazy-deps restores eager cloning behavior.
Git remotes are now used for managing package URLs. Repo forks are added as another git remote, eliminating extra cloning. Unofficial packages are also namespaced using the git remotes.
With this change Atlas now clones all repos using short names, i.e. no more foo.user.github.com/ directories. The history and tags for each remote is also handled using the git remotes which help reduce collision with local branches.
Please file issues for any bugs you encounter.