I work a lot on tooling, because tooling lets me Work Smarter, Not Harder, and they let me exercise my UX skills on a user group that I know a lot about: developers. In the same way doctors make the worst patients, developers can (but not always) make the worst users. These challenges can help one hone their craft in both UX and DX.
They are a particularly good way to slowly roll out new processes in a team or organization, because as the tool matures you can increase your expectations of people to use the tools.
I really should have more posts in this category than I do, given how often I think about it.