A large percentage of the tech workers I have worked with get into the office rarely by ten and often much later around noon. Then they "stay late" until eight or ten or even midnight but when meals and breaks are accounted for they barely put in eight hours of work. An alternative is to arrive at a more traditional work start time and minimize time spent on meals and breaks. This is not about spending more time working but rather about allocating time carefully and densely in order to have a good chance of not staying late.
