In this ACCU 2021 presentation, Undo Engineer Chris Croft-White explains everything you need to know about Time Travel Debugging - including how it works in practice (demo starts at 9:08 minutes).
He takes a sample program with bad data in memory and demonstrates how to step back in time to the point where that bad data was modified - tracing back to the exact point where the error happened.
Time Travel Debugging simplifies debugging by giving developers the superpower to freely step backward or forward in time in a program’s execution.
With this debugging capability, developers can unwind from the point of symptom all the way back to the root-cause to see exactly what happened.
To try Time Travel Debugging for yourself, grab a free trial.