Time-Travel Debugging: Replaying Production Bugs Locally

What they're describing isn't time travel debugging - https://en.wikipedia.org/wiki/Time_travel_debugging.

I'd call this logging calls to your business logic layer. Then running the logged calls on your business logic layer in a development environment to debug the problem.

Your business logic layer should be separate from your UI/presentation layer.

Makes it easy to test them separately if they're not tightly coupled.

Also if you wanna to reuse your business logic layer in a different UI environment, it's easier to switch to another UI if they're not tightly coupled.

Interesting approach. I often get to the same goal by using the replicated state machine pattern. Where all inputs to a system are recorded. Both methods seem to rely on designing your application in a very specific way to be able to replay inputs and deterministically get the same outputs.