Sylius is a PHP e-commerce solution based on Symfony2, a popular PHP framework. It is 100% free and open source and is developed using behavior-driven development (BDD) process. As such, it has an extensible architecture, clean code and robust features making it very developer-friendly.
In terms of e-commerce features, Sylius is packed with all the functionalities you’d expect in any e-commerce solution. It supports product management, inventory tracking, checkout and shipping engines. White its interface is pretty minimalist, it does has a great user experience. You can also easily customize the look-and-feel by implementing your own Twig templates – Twig is a PHP template engine.
The primary advantage of Sylius is that it is split into components and allows you to use only what you need. You can use the full stack ecommerce solution or build your own solution from the decoupled bundles. Plus if you already have an existing Symfony2 application, you can easily plugin Sylius into it.
In terms of documentation, it is a bit limited. If you’re familiar with Symfony2, then you should be able to jump-start your customization. Otherwise, you’ll need to resort to paid training and support offered by KNP Labs, the company behind Sylius.