This dev device accepts custom firmware… I don’t know much Rust, but I guess I could make it create schnorr signatures on arbitrary data.

Arbitrary data like nostr events, or Cashu token 👀 nostr:note18qc0qzz2f83f6cmh2pex2yecthj6t3g98q50y7gca6dd8wrfpyrsjsqm0s