Should I specify exact versions in my Gemfile?

Question

I\'ve noticed that on rubygems.org a lot of the gems suggest you specify them by major version rather than exact version. For example...

The haml-rails gem...

Answer 1

I would definitely say use the exact version numbers. You can probably always just lock it down to a major version, or never specify any version, and be okay, but if you really want that fine grained level of control and to have 100% confidence in your program when being run on other machines, use the exact version numbers.

I've been in situations where the exact version number wasn't specified, and when I or someone else did a bundle install, the project broke because it went to a newer version. This can be especially bad when deploying to production.

Bundler does lock in your gem specifications, but if you're telling it to just use a major release, then it locks that in. So is just knows "Oh the version is locked in at > 0.1" or whatever, but not "Oh the version is locked in specifically at 0.1.2.3".