A software engine has a base system in communication with service subsystems and test subsystems. The base system, the service subsystems, and the test subsystems are software applications that exchange data with one another while operating within the software engine. In one exemplary mode of operation, the base system receives outputs from the service subsystems. In another exemplary mode of operation, the base system receives outputs from the test subsystems that simulate the outputs generated by the service subsystems. An exemplary method of testing the software engine is also provided. Specifically, the illustrative method includes receiving an output during a service mode, switching from the service mode to a testing mode, and receiving the simulated output during the testing mode. The method steps may be performed by a computer executing instructions stored on a computer-readable medium.