core/templates/layout/checkbox.html.tpl

{{define "checkbox"}}
<div class="{{if .options.formClass}}{{.options.formClass}}{{else}}form-group{{end}}">
  <input type="checkbox"
         name="{{.options.name}}"
         class="form-check-input"
         id="{{.options.id}}"
         {{if .update}} value="{{.value}}" {{end}} {{.options.required}}>
  <label class="form-check-label" for="{{.options.id}}">{{.options.label}}</label>
</div>
{{end}}