{ "development_board": { "promicro": { "processor": "atmega32u4", "bootloader": "caterina" }, "elite_c": { "processor": "atmega32u4", "bootloader": "atmel-dfu" }, "proton_c": { "processor": "STM32F303", "bootloader": "stm32-dfu", "board": "QMK_PROTON_C" } } }