It's important that all development happen under the same Ruby version (we have Travis to help with other versions if we so choose) so that all changes are compatible with the latest stable MRI.
It would be superfluous and undesirable to clutter up the repo with .rbenv-version, .rvmrc and other such files, but each of these Ruby Version Managers have made an effort to align with one central version file: .ruby-version.
This PR includes this .ruby-version file, which contains the latest MRI, ruby-1.9.3-p362.
Added support for .ruby-version to ensure congruent dev environment
Thanks, dude! @sstephenson should be releasing rbenv support for this file momentarily. RVM already has it built-in.
Why does everyone who hacks on Jekyll have to use the same Ruby version? Jekyll is supposed to be compatible with all sorts of Rubies.
I think this file should be unversioned.
I agree with @mislav so I submitted a pull request #855