Foundations of Programming - Karl Seguin

Wrapping It Up
Wrapping It Up
WE ALL TEND TO TIE OUR SELF-ESTEEM STRONGLY TO THE QUALITY OF THE
PRODUCT WE PRODUCE - NOT THE QUANTITY OF PRODUCT, BUT THE QUALITY. - TOM
DEMARCO & TIMOTHY LISTER (PEOPLEWARE)
F
or many, programming is a challenging and enjoyable job that pays the bills. However, given that
you've managed to read through all of this, there's a good chance that, like me, programming is
something much more important to you. It's a craft, and what you create means more to you than
probably any non-programmer can understand. I take great pleasure and pride is building something
that stands up to my level of quality, and learning from the parts that I know need to be improved.
It isn't easy to build quality software. A new features here or a misunderstanding there, and our hard
work starts, ever so slightly, to show weakness. That's why it's important to have a truly solid
understanding of the foundations of good software design. We managed to cover a lot of real
implementation details, but at a high level, here are my core principles of good software engineering:
� The most flexible solution is the simplest. I've worked on projects with flexibility built into the
system upfront. It's always been a disaster. At the core of this belief lie in YAGNI, DRY, KISS and
explicitness.
� Coupling is unavoidable, but must be minimized. The more dependent a class is on another
class, or a layer on another layer, the harder your code is to change. I strongly believe that the
path to mastering low-coupling is via unit tests. Badly coupled code will be impossible to test
and plainly obvious.
� The notion that developers shouldn't test has been the anti-silver bullet of our time. You are
responsible (and hopefully accountable) for the code that you write, and thinking that a method
or class does what it's supposed to isn't good enough. The pursuit of perfection should be good
enough reason to write tests, but, there are even better reasons to do so. Testing helps you
identify bad coupling. Testing helps you find awkwardness in your API. Testing helps you
document behavior and expectations. Testing lets you make small and radical changes with far
greater confidence and far less risk.
� It's possible to build successful software without being Agile - but it's far less likely and a lot less
fun. My joys would be short-lived without ongoing customer collaboration. I would quit this field
without iterative development. I would be living in a dream if I required signed off specifications
before starting to develop.
� Question the status quo and always be on the lookout for alternatives. Spend a good amount of
time learning. Learn different languages and different frameworks. Learning Ruby and Rails has
made me a far better programmer. I can pinpoint the beginning of my journey in becoming a
better programmer to a few years ago when I was deeply entrenched in the source code for an
open source project, trying to make heads of tails of it.
Foundations of Programming Copyright © Karl Seguin www.codebetter.com
78