Effective Design Philosophy & Principles

Implementing design principle lessons from Unix/Linux

Undoubtedly, Unix has shaped computing and in many ways the world in which we now live. While Windows still maintains a hold on most desktop OS environments, Unix and it’s parents/progeny (i.e. Linux & OS X) power the vast majority of servers, devices, and will continue to increase exponentially with the Internet of Things. Even Microsoft sees the writing on the wall and has begun to incorporate Linux into Windows.

But how has this software, that was developed in the 1970’s remained so prolific? Certainly, a big part of it can be traced back to the fundamental philosophy and guiding principles that shaped Unix development.

In the book title “The Art of Unix Programming” by Eric Raymond — the author lists the rules that make up the Unix philosophy. More of the Unix philosophy was implied not by what these early designers said but by what they did and the example Unix itself set. These nearly universal concepts provide a strong conceptual framework, and should readily be adopted to guide a vast array of projects.

The abstracted ideas that follow are incredibly powerful in many applications (if not vital) to successful project execution.

1. Rule of Modularity: Write simple parts connected by clean interfaces.
2. Rule of Clarity: Clarity is better than cleverness.
3. Rule of Composition: Design programs to be connected to other programs.
4. Rule of Separation: Separate policy from mechanism; separate interfaces from engines.
5. Rule of Simplicity: Design for simplicity; add complexity only where you must.
6. Rule of Parsimony: Write a big program only when it is clear by demonstration that nothing else will do.
7. Rule of Transparency: Design for visibility to make inspection and debugging easier.
8. Rule of Robustness: Robustness is the child of transparency and simplicity.
9. Rule of Representation: Fold knowledge into data so program logic can be stupid and robust.
10. Rule of Least Surprise: In interface design, always do the least surprising thing.
11. Rule of Silence: When a program has nothing surprising to say, it should say nothing.
12. Rule of Repair: When you must fail, fail noisily and as soon as possible.
13. Rule of Economy: Programmer time is expensive; conserve it in preference to machine time.
14. Rule of Generation: Avoid hand-hacking; write programs to write programs when you can.
15. Rule of Optimization: Prototype before polishing. Get it working before you optimize it.
16. Rule of Diversity: Distrust all claims for “one true way”.
17. Rule of Extensibility: Design for the future, because it will be here sooner than you think.