NOTE: This is a work-in-progress and currently at a pre-alpha, proof-of-concept stage.

To ensure you have all the dependent layers at the expected revision, use the manifest in the chromeos-yocto-manifest git repository.

This umbrella repository holds the individual layers which make up meta-chromeos. In Yocto Project/OpenEmbedded layers can be of different types (distro, bsp and software/functional) and should be kept for the specified purpose in order to pass the Yocto Project Layer Compatibility tests.

Layers in this repository:

• meta-chromeos-distro: High-level "global" settings, such as branding and invasive features (DISTRO_FEATURES) such as systemd or wayland.
• meta-chromeos-bsp: Low-level definition of boards (MACHINEs), tunings, bootloaders and Linux™ kernels.
• meta-chromeos-base: Software/functional layer for the recipes needed to build chromeos-base. This is also where the chromeos-base-image is defined. Most of the work for this proof-of-concept is in this layer.

To set up your build environment:

$ source <path to>/meta-chromeos/cros-init-build-env [build directory]

Many tutorials will tell you to clone other layers as sub-directories of poky and by default put your build directory there as well. This does not work well when working on multiple projects or different build configurations. It is strongly recommended to keep your other layers as siblings of poky and put your build-<purpose> directory on a disk with lots of fast scratch storage.