Assets not compiling - ruby-on-rails

Question

This is driving me crazy - changes to css on my rails site only update when I run rake assets:precompile.
Does anyone know how to fix this, so assets will get compiled as they are changed?
I have a hunch the issue is in this config/environments/development.rb file:
Rails.application.configure do
# Settings specified here will take precedence over those in config/application.rb.
config.assets.compile = true
# 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
# Care if the mailer can't send.
config.action_mailer.raise_delivery_errors = true
# Print deprecation notices to the Rails logger.
config.active_support.deprecation = :log
config.action_mailer.delivery_method = :smtp
config.action_mailer.perform_deliveries = true
config.action_mailer.default_url_options = { :host => "http://localhost:3000/" }
# SMTP settings for gmail
config.action_mailer.smtp_settings = {
address: 'smtp.gmail.com',
port: 587,
domain: 'gmail.com',
user_name: ENV['gmail_username'],
password: ENV['gmail_password'],
authentication: 'plain',
enable_starttls_auto: true
}
# 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
Here is the top of my assets/stylesheets/application.css file:
/*
* This is a manifest file that'll be compiled into application.css, which will include all the files
* listed below.
*
* Any CSS and SCSS file within this directory, lib/assets/stylesheets, vendor/assets/stylesheets,
* or any plugin's vendor/assets/stylesheets directory can be referenced here using a relative path.
*
* You're free to add application wide styles to this file and they'll appear at the bottom of the
* compiled file so the styles you add here take precedence over styles defined in any styles
* defined in the other CSS/SCSS files in this directory. It is generally better to create a new
* file per style scope.
*
*= require_tree .
*= require_self
*/
As well as the top of application.js:
// This is a manifest file that'll be compiled into application.js, which will include all the files
// listed below.
//
// Any JavaScript/Coffee file within this directory, lib/assets/javascripts, vendor/assets/javascripts,
// or any plugin's vendor/assets/javascripts directory can be referenced here using a relative path.
//
// It's not advisable to add code directly here, but if you do, it'll appear at the bottom of the
// compiled file.
//
// Read Sprockets README (https://github.com/rails/sprockets#sprockets-directives) for details
// about supported directives.
//
//= require jquery
//= require jquery_ujs
//= require_tree .
Edit: I should add that this only became a problem once I removed bootstrap...

Answer 1

To solve the issue:
rake assets:clobber
OR
delete the public/assets folder
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