I have the following line in my gemfile:
gem \'client_side_validations\', :git => \"git@github.com:Dakuan/client_side_validations.git\", :branch => \"maste
A late second answer, as I ran into some confusing output from Heroku's build logs which stumped me for a while.
If you have multiple Github hosted gems in your Gemfile, and one of them is inaccessible (in my case, I had accidentally pointed to a private repo of mine), the build logs throw an error like Username not found
or Repository not found
for all the Github hosted gems - even those that are available.