Where function doesn't work with numeric value

support
1

$published is always empty with the following code…

<div class="content">
    {{ $functions := where $.Site.Data.functions "category" (.Title | lower)}}
    {{ $published := where $.Site.Data.functions "version.mode" 1}}
    {{ $filtered := intersect $functions $published }}
    {{- range $filtered }} {{- partial "function.html" . -}} {{ end -}}
</div>

where Data.functions looks like:

[
  {
    "name": "one",
    "category": "math",
    "version": {
      "mode": 1,
    }
  },
  {
    "name": "zero",
    "category": "math",
    "version": {
      "mode": 0,
    }
  }
]