curl --request POST \
  --url https://nexus.gerowallet.io/api/tx/build/stake-registration \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "stakeAddress": "<string>",
  "changeAddress": "<string>",
  "utxos": [
    {
      "txHash": "<string>",
      "address": "<string>",
      "lovelace": "<string>",
      "outputIndex": 1,
      "assets": [
        {
          "policyId": "<string>",
          "assetName": "<string>",
          "quantity": "<string>"
        }
      ],
      "dataHash": "<string>",
      "inlineDatum": "<string>",
      "referenceScriptHash": "<string>"
    }
  ],
  "senderAddress": "<string>",
  "deregister": true,
  "ttl": 123
}
'

{
  "tx_cbor": "<string>",
  "tx_hash": "<string>",
  "estimated_fee": "<string>",
  "estimated_signatures": 123
}