$ brew install teensy_loader_cli
$ brew tap osx-cross/avr
$ brew install dfu-programmer
$ brew install avr-gcc@7
$ echo 'export PATH="/usr/local/opt/avr-gcc@7/bin:$PATH"' >> ~/.bash_profile
or
$ brew tap osx-cross/avr
$ brew tap PX4/homebrew-px4
$ brew update
$ brew install avr-gcc@8
$ brew link --force avr-gcc@8
$ brew install dfu-programmer
$ brew install dfu-util
$ brew install gcc-arm-none-eabi
$ brew install avrdude
$ cd /Users/koishi/dev_private/qmk_firmware/
$ make ergodox_ez:osx_jis_koishi
$ teensy_loader_cli -mmcu=atmega32u4 -w -v ergodox_ez_osx_jis_koishi.hex
$ make ergodox_ez:osx_ansi_koishi
$ teensy_loader_cli -mmcu=atmega32u4 -w -v ergodox_ez_osx_ansi_koishi.hex
If using Karabiner-Elements, will quit
$ make ergodash/rev2:koishi:avrdude
$ make rhymestone:koishi:avrdude
$ make planck/rev6:koishi:dfu-util
$ make thevankeyboards/minivan:koishi
https://github.com/koishi/qmk_firmware/blob/master/keyboards/ergodash/rev2/keymaps/koishi/keymap.c
https://github.com/koishi/qmk_firmware/blob/master/keyboards/rhymestone/keymaps/koishi/keymap.c
https://github.com/koishi/qmk_firmware/blob/master/keyboards/planck/keymaps/koishi/keymap.c