Rob Pike’s 5 Rules of Programming

Copied from users.ece.utexas.edu/~adnan/pike.html

Rob Pike is one of the designers of the Go programming Language and was also a core member of the Unix team at Bell Labs (he was the co-author of The Unix Programming Environment with Brian Kernighan).

He’s also known for his 5 Rules of Programming.

Here’s the five rules…

  • You can't tell where a program is going to spend its time. Bottlenecks occur in surprising places, so don't try to second guess and put in a speed hack until you've proven that's where the bottleneck is.
  • Measure. Don't tune for speed until you've measured, and even then don't unless one part of the code overwhelms the rest.

  • Fancy algorithms are slow when n is small, and n is usually small. Fancy algorithms have big constants. Until you know that n is frequently going to be big, don't get fancy. (Even if n does get big, use Rule 2 first.)

  • Fancy algorithms are buggier than simple ones, and they're much harder to implement. Use simple algorithms as well as simple data structures.

  • Data dominates. If you've chosen the right data structures and organized things well, the algorithms will almost always be self-evident. Data structures, not algorithms, are central to programming.