A method, apparatus, and computer instructions for marking data versioning for code. Responsive to receiving an application programming interface call, a first marking statement in the code and a second marking statement are inserted in the code. A portion of code between the first marking statement and the second marking statement forms a marked section of code. A change made in data in an object caused by execution of the marked portion of code is detected. The detected change is tracked in manner such that the object may be restored to a prior state.