I just had a majorly fun time addressing tech debt, deleting about 15k lines-of-code from a codebase that now has ~45k lines of implementation, and 50k lines of tests. This was made possible by moving from a homegrown auth system to Clerk, as well as consolidating some Cloudflare workers, and other basic stuff. Not as fun as creating the tech debt in the first place, but much more satisfying. Open source repo if you like to read this sort of thing: https://github.com/VibesDIY/vibes.diy/pull/582