1. A computer program product comprising a computer useable medium having a computer readable program, wherein the computer readable program when executed on a computer causes the computer to: receive a selection of one or more segment attributes from an offer provider campaign, the one or more segment attributes defining one or more segments that correspond to one or more offers in the offer provider campaign; generate an expression graph based on the one or more segment attributes; and generate a portable micro-segment object based on the expression tree such that the portable micro-segment object lacks dependence on the offer provider campaign.