I actually heard this from ex-tmax engineer. One of the engineer was debugging the scheduler a day before demo day, poking here and there, inserting sleep(10);

I actually heard this from ex-tmax engineer. One of the engineer was debugging the scheduler a day before demo day, poking here and there, inserting sleep(10); to random places. He merged his debug commit without deleting sleeps so the OS froze on demo. what this implies: they don't have tests, no code review. And they're still developing OS.