RamFuzz is a fuzzer for individual method parameters in unit tests. A unit test can use RamFuzz to generate random parameter values for methods under test. The values are logged, and the log can be replayed to repeat the exact same test scenario. But RamFuzz also allows mutation of the replay, where some parts of the log are replayed while others are replaced by newly generated values. The new run is also logged, yielding a mutated test scenario and allowing the classic fuzzing evolution process of progressively mutating the input until a bug is triggered.