At least Arch has `js`package which gives you js command to obtain JS shell; in fact it is just Mozilla's SpiderMonkey. Anyway, the best option for "standalone

At least Arch has `js`package which gives you js command to obtain JS shell; in fact it is just Mozilla's SpiderMonkey. Anyway, the best option for "standalone JS" is node, mainly because it has a sane way of importing code from other files.