This repo is mainly a playground for custom Grbl versions created by Maniacal Labs, based on the official Grbl. We try to keep this up to date with the latest from official Grbl, but there is no guarantee.
The configs directory contains each custom version which are automatically built by Travis-CI, one per sub-directory. The contents of each directory is merged with the contents of the grbl directory and then built.
At the end of the CI build process the compiled hex files along with the full source trees that built each are uploaded to the builds branch.
You can find the hex files in the release directory and the sources in the code directory of this builds branch.
Finally, this entire repo has been updated to include a grbl.ino file for not only the main grbl source directory but with each sub-config as mentioned above. This means that there is no need to install any of this as a library in order to compile. Simple grab the code for either the main config or for one of the custom configs and open its corresponding grbl.ino file. Then build and upload as you normally would.