The "time travel debugger" solution they use automatically sets numerous breakpoints and then records a tiny, useless fraction of the information needed to actually recreate past state, but is almost certainly slower than any actual, fully-functional time travel debugger by multiple orders of magnitude. That was the same technique used by the built-in gdb "reverse debugging" which, at least historically, resulted in 1,000x-10,000x (yes, really) slowdown compared to modern techniques which are on the order of 2x-10x. And to at least give gdb some credit, gdb reverse debugging was at least a complete time travel debugger since it recorded everything; it was just unusably slow. That is more than can be said about whatever this is. They would be significantly better off in both functionality and performance wrapping literally any other actual time travel debugger solution.

Then we add on their awful, bespoke trace viewer. I originally just chalked it up to them being unaware of standard practices since most people are unfamiliar with time travel debugging and the associated tooling and they just wanted to show off what they did with some bluster. That is excusable, if somewhat unfortunate. But this is the metaphorical equivalent of claiming you have solved the problem of inserting screws because you invented the hammer which is much better at hammering in screws than a brick.

Their marketing statements are unacceptable misrepresentations of their capabilities with respect to commonly-accepted meanings.

It is utterly baffling that this is more popular than the recent UndoDB thread [1]. They have a real time travel debugger and have been doing it for like 15-20 years. They are actual veterans doing quality engineering.

[1] https://news.ycombinator.com/item?id=44076300

Is it like just a trace viewer fed data by debugger-style mechanisms?