Systems and methods for flexible and extensible contact center routing are disclosed. Incoming communications are received at a contact center from one or more customers. A pairing score is determined for each agent capable of servicing the incoming communications for each of the one or more customers based on customer attributes and/or agent attributes that are adjustable and extensible. An incoming communication is routed from a customer to an agent having a highest pairing score with the customer. The incoming communication can be routed on a first communication channel and then switched over to a second communication channel. The first communication channel and second communication channel can be different types of communication channels.