I just dropped this on Printables: A FreeCAD based custom size box generator. I've been using it for all kinds of stuff. Maybe some of you lot will get some use out of it, too.
https://www.printables.com/model/770701-parametric-simple-custom-box-maker-freecad-generat
Plug in your parameters, make a box with filament hinges -- No hardware required. No screws, no nuts, no supports, no glue, no Fusion, no proprietary software, no going cross-eyed looking at OpenSCAD code.
(And yes, the default size in the file will make an M:tG card deck case.)
I'm sure there will inevitably be innumerable variants. I was thinking of adding a generator for Gridfinity inserts, and dividers wouldn't be too tough to add, either. Or handles, or swivel latches, etc., etc.