It’s my own software that I sell licenses to. I’m a solo dev but I have had contractors help me from time to time. 6 years of dev time with over 500K LOC of a wide variety of languages. It’s mostly really dense functional code. It’s an extremely stable code base - once something is built it’s unlikely I’ll ever have to touch it again. One of my primary motivations to do solo dev was to have the freedom to do things properly without ill-informed program managers rushing me into bad decisions.
I keep this account (and all social accounts anonymous) so I can’t share my OSS code. I think self-hosting meta language compilers would be the closest similar code base.
My code is targeted to experienced functional programmers, and others of the same skill level seem to have no trouble with it, but the less experienced will bounce off it. My thinking is that those people should get more experience and come back instead of optimizing my codebase to a lower common denominator for ease of hiring. This has made hiring difficult as anyone who can work on my code base can probably get a high paying job at a FANG. But as a solo dev the productivity gain is enough that I still have no trouble competing in my niche.
