I really like the way that you can upload multiple versions of the same cookbook to Chef server. And also you can specify the cookbook version in metadata file. e.g.
depends 'base-config', '= 1.2.1'
I like Salt. However, I couldn't find any version management and requisite for Salt states/formula. I am really surprised since I think it's a fundamental requirement for a configuration management. Did I miss anything? How do salt handles states/formula file versions?