Various technologies described herein pertain to performing time travel debugging. A computer-executable program can be executed. The computer-executable program can be executable under control of a virtual machine. The virtual machine can interact with a browser system during execution of the computer-executable program. Moreover, nondeterministic events can be logged via an interrogative virtual machine interface (VMI) during the execution of the computer-executable program. The nondeterministic events can be logged as part of event logs. Moreover, the interrogative VMI is between the virtual machine and the browser system. Further, snapshots of the virtual machine can be captured during the execution of the computer-executable program. The snapshots can be captured via the interrogative VMI. At least a portion of the execution of the computer-executable program can be replayed based at least in part on a snapshot and at least a portion of the event logs.