It depends on what you code. For me there must be three things for me to be proud of some codebase:

  1. I could use my creativity (it was not entirely defined problem which just needed to be translated to code).
  2. I have enough time to make it good, not rushed.
  3. Problem was a little over my current competence level, so I could learn something new.

If you only make CRUD forms day in/day out it's hard to be proud of what you do. Creating map display engine which is more performant than anything you have seen to date IS a thing to be proud of (I'm still proud of that one thing, but it's other firm's internal tool, so I can't show you). Unfortunately, for most developers being able to work on such things is very rare. I had maybe 5 such things over my 20 year career.