We've created a lightweight, extensible, dependency-free datepicker based on <a href="https://flatpickr.js.org/" target="_blank">flatpickr</a>.

```html
<script src="[path-to-volta]/js/addons/volta-flatpickr.js"></script>
<link href="[path-to-volta]/dist/css/addons/volta-flatpickr.min.css">
```
Set the following at the end of the <code>body</code>:

```javascript
// Day picker
var datepickerMaxDay = flatpickr('#datepicker-max-day', {dateFormat: "d/m/Y", maxDate: "today", clickOpens: false, allowInput: true, closeOnSelect: false});

var datepickerMaxDayTrigger = document.querySelector('#datepicker-max-day-trigger');
datepickerMaxDayTrigger.addEventListener('click', function() {
    datepickerMaxDay.open();
});

// Month picker
flatpickr('#datepicker-max-month', {mode: "month", dateFormat: "M Y", maxDate: "today", closeOnSelect: false});
```