I also have an active PR under homebrew-core (PR #256889) to have it officially listed but at this point I believe it will be rejected as it includes a non-PyPi binary dependency (save3ds) that the Brew maintainers do not like. So for now this private tap is what I can offer to the users.

Copying the .3dsx to the SD card manually is unnecessary, the script already does this. If your brew formulae is not doing that, you should consider fixing that, maybe by downloading the 3dsx from the release (the 3dsx file goes next to custominstall.py).

Also I have plans to wrap this as a Python module eventually (like ninfs), but I've been quite busy so no plans on when it'll happen. Although I'm not entirely sure how I'll handle the binary executables with this...

Hi just as an update on the brew core PR, I did not have the time to commit a change for the fetching of the 3dsx file before it merged though. Please let me know if you are considering adding this official brew formula, if not I will close this PR.