If you just want a raw ed25519 private key then `head -c32 /dev/urandom` does the job. But usually you want a DER/PEM wrapper or similar, which the openssl cli

If you just want a raw ed25519 private key then `head -c32 /dev/urandom` does the job. But usually you want a DER/PEM wrapper or similar, which the openssl cli tools handle nicely.