20. A system for processing posts in an activity stream, the system comprising: one or more processors; the one or more processors being configured to: receive a client type specifying a type of a client device; receive activity information from an activity source; receive an activity type; create a first protocol buffer using the activity type and the activity information; select embedded code from a library of embedded code based in part upon the client type and the activity type; add the embedded code to the first protocol buffer to create a type-specific protocol buffer; and send the type-specific protocol buffer to the client device for rendering of the activity information.
20. A system for processing posts in an activity stream, the system comprising: one or more processors; the one or more processors being configured to: receive a client type specifying a type of a client device; receive activity information from an activity source; receive an activity type; create a first protocol buffer using the activity type and the activity information; select embedded code from a library of embedded code based in part upon the client type and the activity type; add the embedded code to the first protocol buffer to create a type-specific protocol buffer; and send the type-specific protocol buffer to the client device for rendering of the activity information. 25. The system of claim 20 , wherein the one or more processors are further configured to communicate with the client device and determine the client type.