Code
Some excellent info in the coding style guide. Note, I am not sure when the style guide was last reviewed. There is a comment "(combine with chicken)"?
Documentation
DART specific: documentation style guide
Summary of the google documentation style guide: Documentation Style Guide
Ben has a 'read the docs' version of DART documentation
https://github.com/NCAR/DART-documentation
https://dart-documentation.readthedocs.io/en/latest/
Check for this before converting any DART documentation to reStructuredText (no need to start from scratch)