This is a rather general enquiry. I have a client who have a website using the Silverstripe CMS (Silverstripe CMS » the open source CMS that empowers great web teams » Silverstripe CMS). This client engaged third party developers for some website development who in turn chose to use Mapbox for the map on the website, essentially because the developers were more familiar with using Mapbox within Silverstripe.
I did some web searches but couldn't find much. There was one GitHub repo that talked about using Leaflet.
I'm not familiar with Silverstripe or PHP myself, but if there were any resources out there I would love to have them up my sleeve in case the discussion comes up with my client.