Krayin

Krayin is an open-source CRM built on Laravel, and that framework choice is most of its argument. Extending a CRM usually means learning the vendor's own extension model; here it means writing PHP in a framework that a very large number of working developers already use, against a codebase you can read in full.

What follows from that is data control of the strongest kind available: records on hardware you own, with no third party holding a copy. There is no licence cost, the application runs on infrastructure you provide, and customer records never leave machines you own. For a development shop that wants a CRM shaped precisely to a process, starting from readable code in a familiar framework is a shorter path than configuring somebody else's product.

The cost is everything a vendor normally absorbs. No hosted plan is published, so provisioning, updates, backups and security are yours from the first day. It is also younger and less proven than the established open-source projects in this field, with a smaller community and less accumulated documentation, which matters most at exactly the moment something breaks.