ruby-ed25519 1.2.4-1build1 (s390x binary) in ubuntu groovy

 A Ruby binding to the Ed25519 elliptic curve public-key signature system
 described in RFC 8032.
 .
 Ed25519 is a modern implementation of a Schnorr signature system using
 elliptic curve groups.
 .
 Ed25519 provides a 128-bit security level, that is to say, all known attacks
 take at least 2^128 operations, providing the same security level as AES-128,
 NIST P-256, and RSA-3072.