Load order of the environment

Rails 3, 4, 5, 6

config/application.rb
config/environment.rb before the initialize! call (we don't usually edit this file)
The current environment, e.g. environments/production.rb
Gems
Vendored plugins
All initializers in config/initializers/*.rb
config/environment.rb after the initialize! call (we don't usually edit this file)
Your own code from app

Code in config/preinitializer.rb (if it exists)
environment.rb, code above the Rails::Initializer.run block (put constants here if you want to override them in environments)
environment.rb, the Rails::Initializer.run block
The current environment, e.g. environments/production.rb
Gems
Vendored plugins
All initializers in config/initializers/*.rb
Code below the Rails::Initializer block

Consider reading the Rails initialization process guide Show archive.org snapshot for a deep dive into the initialization process.

Henning Koch

Last edit

15 days ago

Henning Koch

License

Source code in this card is licensed under the MIT License.

You probably know that you can use CSS selectors to match against elements and their attributes, such as:

a[title] { /* any <a> that has a "title" */ }
a[data-fancy="true"] { /* any <a> that has their "data-fancy" attribute set to "true" *...

In Ruby, classes and modules are called constants. This card explains how Ruby resolves the meaning of a constant.

E. g. in the following example, Array could mean either Foo::Array or simply Array:

class Fo...

It is generally discouraged to load your JavaScript by a <script src> tag in the <head>:

<head>
  <script src="app.js"></script>
</head>

The reason is that a <script src> tag will pause the DOM parser until the script has l...

In order to

you can use RSpec's "nested" format. It looks like this:

Tool
  validations
    should require model to be ...

Posted by Henning Koch to makandra dev (2010-09-07 10:08)