BAP Primus is a Microexecutuin Framework. The Microexecution technique was pioneered by Patrice Godefroid from Microsoft Research. The idea is to execute a binary from any point, using random inputs for undefined values.

The idea of Primus is very similiar. A program is lifted into the Intermediate Representation, that is interpreted using the Primus interpreter. The Framework allows users to customize the interpreter by implementing different machine components.