Restart Rails server automatically after every change in controllers - ruby-on-rails

Question

It should not be necessary to restart Rails server after any normal change. However, when I make little changes on my app controllers, they aren't applied if I don't restart the server. Even if I wrote bad code and made errors intentionally, the old error persists. How can I change that or verify that's well set up?
I have in config/environment/development.rb file:
config.cache_classes = false
This didn't work for me.
UDPATE 1:
development.rb
Rails.application.configure do
# Settings specified here will take precedence over those in config/application.rb.
# In the development environment your application's code is reloaded on
# every request. This slows down response time but is perfect for development
# since you don't have to restart the web server when you make code changes.
config.cache_classes = false
# Do not eager load code on boot.
config.eager_load = false
# Show full error reports and disable caching.
config.consider_all_requests_local = true
config.action_controller.perform_caching = false
# Don't care if the mailer can't send.
config.action_mailer.raise_delivery_errors = false
# Print deprecation notices to the Rails logger.
config.active_support.deprecation = :log
# Raise an error on page load if there are pending migrations.
config.active_record.migration_error = :page_load
# Debug mode disables concatenation and preprocessing of assets.
# This option may cause significant delays in view rendering with a large
# number of complex assets.
config.assets.debug = true
# Asset digests allow you to set far-future HTTP expiration dates on all assets,
# yet still be able to expire them through the digest params.
config.assets.digest = true
# Adds additional error checking when serving assets at runtime.
# Checks for improperly declared sprockets dependencies.
# Raises helpful error messages.
config.assets.raise_runtime_errors = true
# Raises error for missing translations
# config.action_view.raise_on_missing_translations = true
end

Answer 1

You can use nodemon for auto restarting your old rails applications.
1) Install nodemon.
sudo npm install -g nodemon
2) Create nodemon.json file on root dir and configure it
{
"ignore": [
".git",
"node_modules/**/node_modules"
],
"watch": [
"app/controllers/",
"app/models/",
"app/assets/",
"config/",
"db/"
],
"ext": "rb yml js css scss"
}
3) Create rails.sh file on root dir to start rails application using nodemon.
kill -9 `cat tmp/pids/server.pid`
echo "APP READY!!!"
echo "Ruby on Rails"
rails s -d
4) Give permission to rails.sh file.
sudo chmod +x rails.sh
5) Start server using sh command.
nodemon -L --exec "./rails.sh"
Note: Steps verified on mac machine. different os may have different command or configuration.