Any comments on what people use to manage the chef cookbooks (and why)?
Librarian or Berkshelf seem to be the two main contenders to make updating cookbooks similar to updating gems with bundler.
Librarian or Berkshelf seem to be the two main contenders to make updating cookbooks similar to updating gems with bundler.
Where they differ is in where they put your cookbooks, and what additional features they offer. Librarian-chef puts your cookbooks in a "cookbooks" folder in the project root, while Berkshelf keeps a global cache of all the versions of each cookbook you've installed outside of the project. Both provide support for uploading your cookbooks to a Chef server, librarian-chef through plain knife and Berkshelf through it's own upload command.
Berkshelf also features scaffolding support for Vagrantfiles and new cookbooks, and generally has extra features specifically for rapidly iterating on cookbooks themselves. It also provides a vagrant plugin to manage bundling/uploading cookbooks to a Vagrant VM, since they need to be copied out of the central repo and made available.
Overall, I've found that I like Berkshelf better. It feels a little more idiomatic, and I like having my cookbook versions shared between projects rather than duplicated everywhere. If you have any specific questions about either, I'd be happy to answer them.
I will note that the librarian-chef also has a vagrant plugin: vagrant-librarian-chef.
No hard numbers, but the main thing is that Berkshelf could not have really happen without enough standardized community cookbooks. By putting the cookbooks into a global directory, it works more like Ruby gems and Bundler: instead of focusing on your customized (and probably divergent) cookbooks loaded into your project directory, you focus only on the few cookbooks that are specific for your needs. It comes out of a bigger theme in the 2012 Summit, that of creating "library cookbooks" that gets assembled by your "application cookbook". If it's a library cookbook, you don't necessarily need it in your project library any more than you need to import a Ruby gem into your Rails directory during development.
Test-kitchen is also worth looking into, though as far as I know, that still uses Librarian under the covers. Berkshelf support for test-kitchen is pending (http://tickets.opscode.com/browse/KITCHEN-9).
In summary: Berkshelf is part of the overall trend in modularizing these cookbooks and developing tighter engineering discipline.
Haven't tried Librarian - only because I saw Berkshelf first and it integrated nicely with Vagrant.
I'd be interested to hear how people were setting up their local chef environments.
If you're looking to use knife solo for setting up production environments, perhaps one thing to look at is Vagrant 1.1+ support for EC2 provisioning (assuming you're using AWS).
You can also have Berkshelf install the declared cookbooks into a directory with `berks install -c $cookbook_dir` and then using knife-solo. Seems awkward, but I'd rather have dependencies managed in some way, rather than resolving the dependencies by hand.