I had started working on something similar a few months back but as a collection of CLI utilities.

The first was a todo list printer where the todos are written in a YAML file. It includes fields for the name of the list and the date.

I also started working on a Sudoku printer (which I think is only possible on 80mm paper). But I completely forgot about the entire thing after coming back from vacation.

You've inspired be to get back to working on it :D

As an aside, are there any good recommendations for a wifi/bluetooth printer using 80mm paper that doesn't break the bank? I initially bought the Munbyn ITPP098P but it being USB only is a bit unergonomic.

Already replied the same in another comment, but I recently got the "YHD-8390" on Aliexpress for around 100$ - has wifi, usb, ethernet, and works pretty well.