I have a work that may be considered a derived work from a GPL'd work and would find it difficult to release the complete source for technical reasons. Is it permissible for me to distribute the documentation for this work by itself without any source code or binaries? Context is that I'd like to provide a technical writing sample on job applications or relate the experience I gained from developing the project in the case that I cannot release the code.
Is documentation for a GPL-derived work covered by the GPL?
No. GPL applies primarily to software source code, not to the documentation. But you can use the GNU Free Documentation License (GFDL) for that. In either case, I think your desire to have a technical writing sample would fall under fair use regardless of almost any mainstream license you picked.
To be covered by the GPL, source files (as well as binary outputs) must contain a copy of the GPL, or reference a license.txt
which contains the GPL in a preamble section. Though uncommon, it is not unknown for many, even closely related source files within a single project to follow different (though hopefully compatible) licenses in this manner.
More info on using the gpl at the gnu website
You should check the license of the documentation it may differ from the license of the software itself.
If the license is not specified, and the GPL covers all the project, thus the documentation may be as well subject to GPL.
(I'm not a lawer, so no guaranees on what I suggest)