The "easy" way to flash the firmware is using a tool from your host OS like the Teensy programming app. [ErgoDox EZ](keyboard/ergodox_ez/readme.md) gives a great example.
If you want to program via the command line you can uncomment the ['modifyvm'] lines in the Vagrantfile to enable the USB passthrough into Linux and then program using the command line tools like dfu-util/dfu-programmer or you can install the Teensy CLI version.
+
\ No newline at end of file