Welcome to OpenEmbedded, the build framework for embedded Linux. OpenEmbedded offers a best-in-class cross-compile environment. It allows developers to create a complete Linux Distribution for embedded systems. Some of the OpenEmbedded advantages include:
adopted as the build system for the Yocto Project in March 2011.
support for many hardware architectures
multiple releases for those architectures
tools for speeding up the process of recreating the base after changes have been made
easy to customize
runs on any Linux distribution
cross-compiles 1000's of packages including GTK+, Qt, the X Windows system, Mono, Java, and about anything else you might ever need
https://www.openembedded.org/wiki/Main_Page
https://www.openembedded.org/wiki/Commit_Patch_Message_Guidelines