YAML Sortkey is an atom package that not only automatically validates your YAML files while you develop, but also gives you the option to automatically sort the keys on file save.
Full Demo: https://www.youtube.com/watch?v=s-GNDcK0Nq0
- Install via Atom's Package manager by searching for "yaml-sortkey"
Yaml Sortkey: Validate
Yaml Sortkey: Sort Keys
- Autosort Directories: Accepts an array of file paths in which all yaml files within those paths will be autosorted before saving.