Comment by kaipereira

I used https://eds.st.com/antenna/#/ to get an antenna that fit with a target inductance of 4.7uH and then used https://github.com/nideri/nfc_antenna_generator to create the footprint which I slightly modified for the board! You can read a bit more about it in the journal (JOURNAL.md)!

It was really satisfying to get everything working (especially the NFC because I've found RF to be a bit tricky), but the eink logic was actually a bit of gamble, because I broke my only eink while prototyping so the production batch was the first test of the driver. So always carry spare components when designing prototypes!