Oledrion (MyShop) is the best and most comprehensive e-Commerce module developed natively for XOOPS!

It was developed originally by Hervé Thouzard (aka Hervet) from XOOPS France, and lately it was enhanced by Hossein Azizabadi (aka Voltan) from XOOPS Iran.

I am working right now on a tutorial for Oledrion - it is still work in progress, but you can read it already on GitBook

But it would be fantastic if some of you could fork it on GitHub and contribute to it, and make it better!