Damn, is he actually that humble or is it just a persona?

Skip to around 4:15 for the actual content.

He's a smart kid and obviously likes himself to a degree that gets a bit annoying but his achievements are quite something. I still find the presentation style pretty entertaining.

That's actually him. The stories of his shitty behavior when he was in college and Didn't Have To Do The Work Because Don't You Know Who I Am (which didn't work out so well) still circulate in my friend groups.

qira is cool but it doesn't scale. It singlesteps the program, recording the effects of each instruction in a fairly naive way. gdb's built-in reverse execution is similar. It's roughly a factor of 1000x slowdown and requires massive storage.

Getting the overhead down to < 2x (for rr) or 10x (for TTD), with reasonable trace sizes, requires much higher tech ... and is absolutely necessary for most users.

Yep, http://qira.me/