An example method of preserving a modification to an internal state of a computer system includes applying an overlay on a target container. The overlay includes a set of events corresponding to a first set of modifications to a computer system. The method also includes after applying the overlay, receiving a set of user requests corresponding to a second set of modifications to the computer system. The method further includes changing, based on the set of user requests, the third set of internal states of the computer system to the fourth set of internal states. The method also includes removing the overlay from the target container, while preserving the second set of modifications to the computer system.