Export SVM Private Key

import xyz.dynamic.waas.svm.DynamicSvmWalletClient;

String secretSeedB58 = client.exportPrivateKey(
    walletProperties,
    externalServerKeyShares
).join();

// base58-encoded 32-byte secret seed
System.out.println("Secret seed: " + secretSeedB58);

import software.sava.core.encoding.Base58;

byte[] seed   = Base58.decode(secretSeedB58);                              // 32 bytes
byte[] pubkey = Base58.decode(walletProperties.accountAddress());          // 32 bytes

byte[] keypair64 = new byte[64];
System.arraycopy(seed,   0, keypair64,  0, 32);
System.arraycopy(pubkey, 0, keypair64, 32, 32);

// keypair64 is the standard Solana Keypair byte layout — load it into
// solana-js / solana-py / sava as you would any external keypair.