Create this in the config/initializers folder file and add it to .gitignore and you would be able to change configuration values in your local Rails development environment without affecting other developers, you can even "decorate" application classes to customize results

local_development_config.rb

# Override configuration options here
Rails.application.config.force_ssl = false
Rails.application.config.action_controller.asset_host = nil
Rails.application.config.action_mailer.asset_host = nil

# Decorators to override Application Classes
Rails.application.config.to_prepare do

  # Override sessions controller to automatically login as the first user
  SessionsController.class_eval do
    def new
      if request.host == 'localhost' && Rails.env.development?
        Rails.logger.info "Overriding login in development environment"
        log_in User.first
        redirect_to root_url
      end
    end
  end
end