github.com/opencoff/go-sign (go): Package sign implements Ed25519 signing, verification on files. It builds upon golang.org/x/crypto/ed25519 by adding methods for serializing and deserializing Ed25519 private & public keys. In addition, it works with large files - by precalculating their SHA512 checksum in mmap'd mode and sending the 64 byte signature for Ed25519 signing.
Keywords: cryptographic-checksum|ed25519|ed25519-serialization|file-checksum|golang