How to add all assets inside app/assets to assets:precompile task References (I adapted from those links): http://stackoverflow.com/questions/10097993/rails-config-assets-precompile-setting-to-process-all-css-and-js-files-in-app-as http://stackoverflow.com/questions/12613980/how-do-i-use-config-assets-precompile-for-directories-rather-than-singl…

production.rb

# Put that on config/environments/production.rb

config.assets.precompile << lambda do |path|
  if path =~ /\.(css|js)\z/
    full_path = Rails.application.assets.resolve(path).to_path
    app_assets_path = Rails.root.join('app', 'assets').to_path
    return true if full_path.starts_with? app_assets_path
  end
  false
end

Remember to remove:

//= require_tree . # from application.js
and

*= require_tree . # from application.css

Require manually each file need in the manifests.