From UNIX to today

2 min read

UNIX philosophy

do one thing and do it well

work together

handle text streams, because that is a universal interface

UNIX components

  • minimalist
  • modular
  • simple
  • short
  • clear
  • extensible
  • composable
  • easily maintainable

Agile manifesto

  • Individuals and interactions over processes and tools

  • Working software over comprehensive documentation

  • Customer collaboration over contract negotiation

  • Responding to change over following a plan

The cycle

plan before coding

keep it simple




pair programming


code reuse

small methods

small classes


do not optimize early

Measure. Don’t tune for speed until you’ve measured

do one thing well

So much complexity in software comes from trying to make one thing do two things.


first, make it work, then make it faster

keep it simple

you ain’t gonna need it

Perfect is the enemy of good

If it ain’t broke, don’t fix it

Gold plating, Nirvana fallacy, over engineering

KISS keep it simple, stupid

Define must - should - could -won’t

The simplest thing that could possibly work

“The cheapest, fastest, and most reliable components are those that aren’t there.” – Gordon Bell


Hide complexity Selectively reveal


“Only amateurs attack machines; professionals target people.” – Bruce Schneier

Security at the expense of usability comes at the expense of security.


“By far the dominant reason for not releasing sooner was a reluctance to trade the dream of success for the reality of feedback.” – Kent Beck

“Real artists ship.” – Steve Jobs

Anything that works is better than anything that doesn’t

The most important input to this learning is customer feedback, deliver working software to customers early & often.

Project Management

Brooks’s law: Adding manpower to a late software project makes it later.

Too much work in progress causes problems.

Always back everything up! Accept responsibility for your own mistakes. And never make changes in production!


“As a rule, software systems do not work well until they have been used, and have failed repeatedly, in real applications.” – David Parnas

“A complex system that works is invariably found to have evolved from a simple system that worked. The inverse proposition also appears to be true: A complex system designed from scratch never works and cannot be made to work.” – John Gall

Question your assumptions. Bad assumptions cause bugs.

If you’ve chosen the right data structures and organized things well, the algorithms will almost always be self-evident.


Ask For Feedback Early

Get End-to-End First

Step Away From the Keyboard

You Can DRY Off Later

no deploy fridays

Take Meticulous Notes

January 15, 2020