I really hope that was said in context of non-contiguous sleep deprivation. 120 hours continually awake is nuts. I've done 96 hours before and I could only do

I really hope that was said in context of non-contiguous sleep deprivation. 120 hours continually awake is nuts. I've done 96 hours before and I could only do borderline mindless tasks at 20% efficiency, let alone programming. It's possible to get a few hours each night, work literally every waking hour and be productive for weeks on end (at great peril of course), but for most developers I'd wager productivity is drastically reduced after 48 hours, and almost completely gone by 72. Recent science says sleep deprivation actually incurs brain damage, so it's definitely never a good idea except for emergencies.