I have a variety of boards - an OrangePiPlus, a hummingboard, a RaspberryPi, a RaspberryPi2 that I can test - as well as a bunch of other boards that are not supported. 

 

I am an embedded linux developer so I have reasonable competence with building kernels, writing drivers, scripting ....

 

I would be interested in helping with testing and fixing things atleast with those boards that I have available to me. 

 

But I could use some clues. 

 

Is there a developers guide to Armbian ? Something that lays out how the build process works ? Or does one just jump in ?

 

As an example it does not appear that install-nand-state is working for either the legacy or vanila builds of the OrangePiPlus. 

 

Is this a script problem or a driver problem ?

 

Ethernet does not seem to be working for the Vanilla build - I am guessing that is a driver issue. 

 

 

Is there a developers guide to Armbian ? Something that lays out how the build process works ?

No, once you spend enough time with build script, you just know how it works 

Problem with such documentation is keeping it up to date because of ongoing changes.

 

 does one just jump in ?

For fixing issues, updating kernel configuration or adding new boards - sure, just make a pull request to main repository.

For reworking or refactoring anything it's better to discuss it before (here in "Armbian build framework" subforum or on GitHub).