Atlas v0.12 is available! It's significantly faster.
To achieve this it has been refactored to create a local "mini-package" cache and to re-use git repo meta-data.
Here's the results with a "reinstall" (e.g. after doing an update):

Much faster!
The quickest way to update is usually with Nimble since your PATH's are probably already setup:
nimble install "https://github.com/nim-lang/atlas@#31eec78100bae17614bc2b45b4660c08ed47efce"Side note: the package cache design opens up the possibility of packages!
Atlas itself may not be the right place, but after this refactor Atlas can be used as a library to parse and cache package info. The static Nimble parser has been well tested and supports 99%+ of Nimble packages out there even including when defined(macosx): or other similar statements.