title: Transformation List of Lists with Jolt
body: <p>I have one JSON like this:</p>
  <pre class="lang-json prettyprint-override"><code>{
    &quot;item1&quot;: [
      &quot;serv1&quot;,
      &quot;serv2&quot;,
      &quot;serv3&quot;
    ],
    &quot;item2&quot;: [
      {
        &quot;obj&quot;: [
          &quot;matriz1&quot;,
          &quot;matriz2&quot;,
          &quot;matriz3&quot;
        ]
      },
      {
        &quot;obj&quot;: [
          &quot;matriz4&quot;,
          &quot;matriz5&quot;,
          &quot;matriz6&quot;
        ]
      }
    ]
  }
  </code></pre>
  <p>And I need to obtain this output:</p>
  <pre class="lang-json prettyprint-override"><code>{
    &quot;item1&quot;: [
      &quot;serv1&quot;,
      &quot;serv2&quot;,
      &quot;serv3&quot;
    ],
    &quot;item2&quot;: [
      [
        &quot;matriz1&quot;,
        &quot;matriz2&quot;,
        &quot;matriz3&quot;
      ],
      [
        &quot;matriz4&quot;,
        &quot;matriz5&quot;,
        &quot;matriz6&quot;
      ]
    ]
  }
  </code></pre>
  <p>I'm trying with this JOLT spec:</p>
  <pre class="lang-json prettyprint-override"><code>[
    {
      &quot;operation&quot;: &quot;shift&quot;,
      &quot;spec&quot;: {
        &quot;item1&quot;: &quot;item1&quot;,
        &quot;item2&quot;: {
          &quot;*&quot;: {
            &quot;obj&quot;: &quot;item2&quot;
          }
        }
      }
    }
  ]
  </code></pre>
  <p>But the output contains 3 elements of the first array, and then the second array like I want.</p>
  <pre class="lang-json prettyprint-override"><code>{
    &quot;item1&quot;: [
      &quot;serv1&quot;,
      &quot;serv2&quot;,
      &quot;serv3&quot;
    ],
    &quot;item2&quot;: [
      &quot;matriz1&quot;,
      &quot;matriz2&quot;,
      &quot;matriz3&quot;,
      [
        &quot;matriz4&quot;,
        &quot;matriz5&quot;,
        &quot;matriz6&quot;
      ]
    ]
  }
  </code></pre>
  <p>What could be the correct JOLT spec to obtain the correct output?</p>