Various exemplary embodiments relate to a method, network node, and machine-readable medium including one or more of the following: instructions for processing a received Diameter message according to a plurality of proxylets; and instructions for defining a plug-in framework as a proxylet of the plurality of proxylets, including: instructions for retrieving a plug-in chain identifying a sequence of plug-ins; instructions for determining a current plug-in based on the plug-in chain; and instructions for evaluating plug-in instructions associated with a current plug-in.