MB - The Meta-Build wrapper

MB is a simple wrapper intended to provide a uniform interface to either GYP or GN, such that users and bots can call one script and not need to worry about whether a given bot is meant to use GN or GYP.

It supports two main functions:

1. "gen" - the main gyp_chromium / gn gen invocation that generates the Ninja files needed for the build.

2. "analyze" - the step that takes a list of modified files and a list of desired targets and reports which targets will need to be rebuilt.

We also use MB as a forcing function to collect all of the different build configurations that we actually support for Chromium builds into one place, in //tools/mb/mb_config.pyl.

For more information, see:

• The User Guide
• The Design Spec