How do bootstrapped companies decide product road maps?

A friend is writing a book about how bootstrapped founders decide their product roadmap. It's going to be very interesting - I've seen some early research. It's fascinating.

They're looking to interview some more founders to include in the book.

Are you the founder of a software company that is:

Bootstrapped (or mostly bootstrapped) Profitable Stable Mature Well-run Around 15 to 50 employees (give or take)

Will put link to LinkedIn post in comments and if you want to take part, get in touch.