A simple and flexible method to sign arbitrary OP_RETURN data with Bitcoin ECDSA signatures. Authors: Attila Aros, Satchmo Special thanks to Monkeylord and Unwriter for feedback and ideas. Note: Use the bitcoinfiles-sdk to build, sign, and verify document signatures. Inspired by techniques described by Monkeylord at https://github.com/monkeylord/bitcoin-ibe Built on top and leveraging Bitcoin Data Protocol by Unwriter at https://b.bitdb.network/ […]