Rushing to optimize before the bottlenecks are known may be the only error to have ruined more designs than feature creep. From tortured code to incomprehensible data layouts, the results of obsessing about speed or memory or disk usage at the expense of transparency and simplicity are everywhere. They spawn innumerable bugs and cost millions of man-hours - often, just to get marginal gains in the use of some resource much less expensive than debugging time

The combination of threads, remote-procedure-call interfaces, and heavyweight object-oriented design is especially dangerous... if you are ever invited onto a project that is supposed to feature all three, fleeing in terror might well be an appropriate reaction.

When you lose interest in a program, your last duty to it is to hand it off to a competent successor.

If Unix could present the same face, the same capabilities, on machines of many different types, it could serve as a common software environment for all of them.

Prototype, then polish. Get it working before you optimize it

Given enough eyeballs, all bugs are shallow (e.g., given a large enough beta-tester and co-developer base, almost every problem will be characterized quickly and the fix obvious to someone).

Provided the development coordinator has a communications medium at least as good as the Internet and knows how to lead without coercion, many heads are inevitably better than one.