Differential fuzzing (and the closely related metamorphic testing) are amazing ideas, I've used them in three different ways: 1) Compare two programs 2) Gener

Differential fuzzing (and the closely related metamorphic testing) are amazing ideas, I've used them in three different ways: 1) Compare two programs 2) Generate two inputs for one program which should produce the same output 3) generate two inputs for one program where there is a simple relationship between the outputs. In all cases, it has been a great way of testing, and has shuck out some incredibly subtle bugs I don't think we would have found any other way.