After a longer break I managed to draw the symbols and footprints of the SAML22G and the IR transceiver module, so I would not have to rely on licenses of external sources. With that I was able to finalise a first prototype board and send it to JLCPCB for production. With the recent pink PCBs that boardhouses now produce I was very tempted, but I opted for a set of 5 green PCBs instead. I decided to run the board on 2.5V, which makes it easy for the AP2112K to work with the battery voltages of a LiPo battery, without running into dropout voltages first. There is some room and I'm tempted to add a footprint for a compass chip in the future, but I can always just connect to the QWIIC connector, as long as they are okay with 2.5V. Should have thought about that.