Programmers of FC: What's your favorite niche open source project?

zsh-autosuggestions
btdu
periods (for PostgreSQL)
ephemeral_pg

computer programmer, information collector, archivist-librarian with a few items, puzzle game appreciator; github.com/ivan 

I have a 2TB PostgreSQL database with 3 billion rows used to track content; I use periods so that I can UPDATE without losing old data, and I use ephemeralpg for unit tests and ad-hoc experimentation to avoid risking a production server. I have no real alternatives to PostgreSQL so I am glad that it is pretty adequate.

what makes you spend so much time with pg-related utitilies?