Configuration files for rails can be found in
config/environments/. By default rails has 3 environments,
test. By editing each file you are editing the configuration for that environment only.
Rails also has a configuration file in
config/application.rb. This is a common configuration file as any settings defined here are overwritten by the config specified in each environment.
You add or modify configuration options within the
Rails.application.configure do block and configuration options start with