boards/adafruit/feather_nrf52840/board.yml

board:
  name: adafruit_feather_nrf52840
  full_name: Feather nRF52840 (Express, Sense)
  vendor: adafruit
  socs:
    - name: nrf52840
      variants:
        - name: uf2
        - name: sense
          variants:
            - name: uf2