Elastic Beanstalk Rails deploy mystery initialize error

I am trying to deploy an existing heroku app to EC2 using Beanstalk.

So far I have all the Environment variables moved over and the database setup.. etc. It seems to work and deploy correct except for Puma.

The puma.log file has the following in it over and over;

/opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/pathname.rb:397:in `initialize': no implicit conversion of nil into String (TypeError)
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/pathname.rb:397:in `new'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/pathname.rb:397:in `join'
    from /var/app/current/config/initializers/cloudfront-signer.rb:2:in `block in <top (required)>'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/cloudfront-signer-2.2.0/lib/cloudfront-signer.rb:108:in `configure'
    from /var/app/current/config/initializers/cloudfront-signer.rb:1:in `<top (required)>'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:268:in `load'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:268:in `block in load'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:240:in `load_dependency'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:268:in `load'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/engine.rb:652:in `block in load_config_initializer'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/notifications.rb:166:in `instrument'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/engine.rb:651:in `load_config_initializer'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/engine.rb:616:in `block (2 levels) in <class:Engine>'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/engine.rb:615:in `each'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/engine.rb:615:in `block in <class:Engine>'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/initializable.rb:30:in `instance_exec'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/initializable.rb:30:in `run'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/initializable.rb:55:in `block in run_initializers'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:226:in `block in tsort_each'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:348:in `block (2 levels) in each_strongly_connected_component'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:420:in `block (2 levels) in each_strongly_connected_component_from'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:429:in `each_strongly_connected_component_from'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:419:in `block in each_strongly_connected_component_from'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/initializable.rb:44:in `each'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/initializable.rb:44:in `tsort_each_child'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:413:in `call'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:413:in `each_strongly_connected_component_from'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:347:in `block in each_strongly_connected_component'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:345:in `each'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:345:in `call'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:345:in `each_strongly_connected_component'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:224:in `tsort_each'
    from /opt/rubies/ruby-2.2.2/lib/ruby/2.2.0/tsort.rb:203:in `tsort_each'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/initializable.rb:54:in `run_initializers'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/application.rb:352:in `initialize!'
    from /var/app/current/config/environment.rb:5:in `<top (required)>'
    from config.ru:3:in `require'
    from config.ru:3:in `block in <main>'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/rack-1.6.4/lib/rack/builder.rb:55:in `instance_eval'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/rack-1.6.4/lib/rack/builder.rb:55:in `initialize'
    from config.ru:in `new'
    from config.ru:in `<main>'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/rack-1.6.4/lib/rack/builder.rb:49:in `eval'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/rack-1.6.4/lib/rack/builder.rb:49:in `new_from_string'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/rack-1.6.4/lib/rack/builder.rb:40:in `parse_file'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/configuration.rb:102:in `load_rackup'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/configuration.rb:69:in `app'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/runner.rb:123:in `app'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/runner.rb:130:in `start_server'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/cluster.rb:213:in `worker'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/cluster.rb:109:in `block (2 levels) in spawn_workers'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/cluster.rb:109:in `fork'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/cluster.rb:109:in `block in spawn_workers'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/cluster.rb:105:in `times'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/cluster.rb:105:in `spawn_workers'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/cluster.rb:157:in `check_workers'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/cluster.rb:421:in `run'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/lib/puma/cli.rb:216:in `run'
    from /opt/rubies/ruby-2.2.2/lib/ruby/gems/2.2.0/gems/puma-2.11.2/bin/puma:10:in `<top (required)>'
    from /opt/rubies/ruby-2.2.2/bin/puma:23:in `load'
    from /opt/rubies/ruby-2.2.2/bin/puma:23:in `<main>'

I have no clue what this is or why its happening and am at a complete loss..

Line 5 of config/environment is Rails.application.initialize!

Line 3 of config.ru is run Rails.application

So does this mean that Rails.application hasn't been defined? I'm a tad confused.

Again this app works perfectly on Heroku.

Suggestions?