Use `make -f Makefile.pjrc` if you want to use PJRC stack but I find no reason to do so now.
## Keymap
Several version of keymap are available in advance but you are recommended to define your favorite layout yourself. To define your own keymap create file named `keymap_<name>.c` and see keymap document(you can find in top README.md) and existent keymap files.
To build firmware binary hex file with a certain keymap just do `make` with `KEYMAP` option like: