Multiple configuration files in SettingsLogic

settings.rb

class Settings < Settingslogic
  source "#{Rails.root}/config/application.yml"
  
  if Rails.env == 'development'
    namespace 'development-' + Socket.gethostname.gsub(/\W/, '-').gsub(/[-]{2,}/, '-')
  else
    namespace Rails.env
  end
      
  # load local settings
  begin
    hash = YAML.load(ERB.new(File.read("#{Rails.root}/config/application_local.yml")).result)[Rails.env]
    instance.deep_merge!(hash)
  rescue => e
  end
end

Additionally, I think you should also remember to define the reload! method so we can ensure local settings will be keep loaded though user have refresh settings from application.yml. The version after refactor will be like:

class Settings < Settingslogic
  def self.load_local_settings
    if File.exist?("#{Rails.root}/config/application_local.yml")
      puts '===> Local application configuration file loaded.'
      instance.deep_merge!(Settings.new("#{Rails.root}/config/application_local.yml"))  
    else
      puts '===> Local application configuration file no found.'
    end
  end

  load_local_settings   # load when first time load Settings

  def self.reload!
    super
    load_local_settings    # load local settings each time refreshing settings
  end