Applications running in Scalingo’s infrastructure are running on a distribution
of Linux with the architecture
amd64. If you are using Windows to develop
your application, incompatibility may occur.
When you are running
bundle install to install the dependencies of your
project, Bundler will select the best versions possible for each gem you’ve
listed in your
Gemfile. Some of these gems have special version for Windows.
As Scalingo’s stack is based on Linux, we can’t install these precise versions.
Specify explicitly your gems version
As a result, the
Gemfile.lock won’t be considered when a Windows machine is
deploying a Ruby application. So you need to lock the versions manually by
gem 'rails', '4.2.0'
If the version has not been specified, it will let Bundler install the last version compatible for your
project. That’s probably not what you want and may probably break your application. So you have to ensure
that all the gems in your
Gemfile have a version specified.