So Plek was the only gem that didn't have any kind of version lock on it so I added a pessimistic version constraint, as is considered [best practice in managing dependencies in a Gemfile](http://robots.thoughtbot.com/a-healthy-bundle). Looking at the Gemfile, the other gem declarations could probably do with a tweak: most of the gems follow semantic versioning so a pessimistic version declaration makes more sense than an exact version as it makes keeping the gems up-to-date easier.