cooperative-market/pos_keyboard/data.xml

<?xml version="1.0" encoding="utf-8"?>
<!--Copyright 2015 igallyamov <https://github.com/igallyamov>
    Copyright 2016 ufaks <https://github.com/ufaks>
    License LGPL-3.0 or later (https://www.gnu.org/licenses/lgpl.html). -->
<openerp>

        <template id="assets" inherit_id="point_of_sale.assets">
            <xpath expr="." position="inside">
                <script type="text/javascript" src="/pos_keyboard/static/src/js/pos.js"></script>
            </xpath>
        </template>
        
</openerp>