Yup. Not Cashu, but precursors.

.That’s what’s so attractive about ecash. Chaum invented it using RSA in the early 80s, Wagner updated with ECC in mid 90s, Phyroo revived with libsecp256k1 in 2002, nostr:npub12rv5lskctqxxs2c8rf2zlzc7xx3qpvzs3w4etgemauy9thegr43sf485vg created #Cashu.

Just standing on the shoulders of giants realizing entirely new possibilities.