Banjo chord diagram generation liberally sourced from https://tex.stackexchange.com/questions/500427/drawing-an-accurate-guitar-fretboard-with-tikz
git submodule update --init --recursive
perl generate_major_chord.pl # generate Makefile and generate_anki_deck.py
make -C build # generate pngs
cd build && python3 generate_anki_deck.py # build Anki deck