# Source code directory structure

## Overview

The source code of atom-shell is separated into a few parts, and we are mostly
following Chromium on the separation conventions.

You may need to become familiar with [Chromium's multi-process
architecture](http://dev.chromium.org/developers/design-documents/multi-process-architecture)
to understand the source code better.

## Structure of source code

* **atom** - Source code of atom-shell.
  * **app** - Contains system entry code, this is the most basic level of the
    program.
  * **browser** - The frontend including the main window, UI, and all browser
    side things. This talks to the renderer to manage web pages.
    * **lib** - Javascript part of browser initialization code.
    * **ui** - Implementation of UI stuff for different platforms.
      * **cocoa** - Cocoa specific source code.
      * **gtk** - GTK+ specific source code.
      * **win** - Windows GUI specific source code.
    * **default_app** - The default page to show when atom-shell is started
      without providing an app.
    * **api** - The implementation of browser side APIs.
       * **lib** - Javascript part of the API implementation.
    * **net** - Network related code.
  * **renderer** - Code that runs in renderer.
    * **lib** - Javascript part of renderer initialization code.
    * **api** - The implementation of renderer side APIs.
       * **lib** - Javascript part of the API implementation.
  * **common** - Code that used by both browser and renderer, including some
    utility functions and code to integrate node's message loop into Chromium's message loop.
    * **lib** - Common Javascript initialization code.
    * **v8** - Utility functions for using V8 and node APIs.
    * **api** - The implementation of common APIs, and foundations of
      atom-shell's built-in modules.
       * **lib** - Javascript part of the API implementation.
  * **spec** - Automatic tests.
  * **script** - Scripts for building atom-shell.
* **chrome** - Source code modified from Chromium's chrome component.

## Structure of other directories

* **vendor** - Build dependencies.
* **tools** - Helper scripts used by gyp files.
* **node_modules** - Third party node modules used for building or running
  specs.
* **out** - Output directory for `ninja`.
* **dist** - Temporary directory created by `script/create-dist.py` script
  when creating an distribution.
* **node** - Downloaded node binary, it's built from
  https://github.com/atom/node/tree/chromium-v8.
* **frameworks** - Downloaded third-party binaries of frameworks (only on
  Mac).