Depot Tools

1. You'll need to have the depot tools installed:

2. You need Git installed: http://git-scm.com/

Linux (Ubuntu/Debian)

This, and more, is described on the Chromium site:

A script is provided for Ubuntu, which is available after your first gclient sync:
$ ./build/install-build-deps.sh

Pulse Audio is missing from the script. On Ubuntu, this is provided by the libpulse-dev package.

Although the install-build-deps.sh script is the recommended method, it will install much more than you need. Here is a (hopefully complete) minimal list of packages to install (sudo apt-get install...):

g++ (>= 4.2)
python (>= 2.4)
libnss3-dev >= 3.12
libasound2-dev
libpulse-dev
libjpeg62-dev
libxv-dev
libgtk2.0-dev
libexpat1-dev

For 32-bit builds on a 64-bit system:
lib32asound2-dev
ia32-libs

Tips for other distributions are available on the Chromium page.

Windows

Follow step 1 in Chromium's build instructions: http://www.chromium.org/developers/how-tos/build-instructions-windows

OS X

XCode 3.0 or higher

Android

These instructions are tested on a Linux development machine.
In WebRTC, we're using the same Android toolchain as Chrome (the one that is downloaded into third_party/android_tools). So you don't need to install NDK/SDK separately.
  1. Install Chrome's Linux prerequisites
  2. Install depot_tools
  3. Install Java OpenJDK as described at Android prerequisites