emergent design: cakes, showers and electricians
TRANSCRIPT
c a k e s , s h o w e r s a n d e l e c t r i c i a n s
EMERGENT DESIGN
Rouan Wilsenach @rouanw
rouanw.github.io thoughtworks.com
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It is not enough for code to work.
- Robert Martin
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WHY DESIGN ?
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9 ANDY GREENBERG/WIRED
10Steve Jurvetson
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Easy to learn Fast to changeFewer bugs
WHY EMERGENT ?
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14https://www.flickr.com/photos/chrisny2/4637837938
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Build. Measure. Learn.
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emerge
verb • become apparent
https://www.flickr.com/photos/schnappi/2321628609
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not
become well-designed
https://www.flickr.com/photos/evaysucamara/5438832695
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a change made in analysis for $1 would cost thousands
to fix in production
- The change curve
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a change made in analysis for $1 would cost thousands
to fix in production
- The change curve
SIMPLICITYWhat is good design?
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Why is this so hard? - Every developer, ever
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a system made out of genuinely simple parts, is going to be able to
affect the greatest change with the least work
- Rich Hickey
23http://martinfowler.com/bliki/BeckDesignRules.html
AWAY FROM !
THE CODE
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Talk about it
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Draw something
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Know your challenges
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Where are we going?
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IN FRONT OF !
THE CODE
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refactoring
noun • a change made to the internal structure of software to
make it easier to understand and cheaper to modify without
changing its observable behaviour
http://martinfowler.com/bliki/DefinitionOfRefactoring.html
BEFOREPreparatory refactoring
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Make the change easy (warning: this may be hard), then make the easy change
- Kent Beck
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You must kill all your darlings
- William Faulkner
DURINGContinuous refactoring
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Don’t forget the last step
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Talk through it
AFTERTake a step back
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When writing code we should always be
thinking of the reader - Martin Fowler
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Always leave the campground cleaner than you found it.
- The boy scout rule, Robert Martin
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Perfect is the enemy of good.
- Voltaire
RECAPAgain! Again!
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Build. Measure. Learn.
Working code is not enough
change the change curve
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Simplicity
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In front of the code
Away from the code
SOME RESOURCES
Articles
• http://martinfowler.com/articles/designDead.html
• http://martinfowler.com/bliki/BeckDesignRules.html
• bit.ly/nf-ead-all (Neal Ford)
Videos
• http://www.infoq.com/presentations/Simple-Made-Easy (Rich Hickey)
• https://vimeo.com/16955608 (Neal Ford)
Books
• http://www.amazon.com/Clean-Code-Handbook-Software-Craftsmanship/dp/0132350882 (Uncle Bob)
• http://www.amazon.com/Extreme-Programming-Explained-Embrace-Edition/dp/0321278658 (Kent Beck)
News
• http://www.wired.com/2015/07/hackers-remotely-kill-jeep-highway/
• http://motherboard.vice.com/en_uk/read/how-is-critical-life-or-death-software-tested
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a m e t a p h o r m a s h - u p
EMERGENT DESIGN
Rouan Wilsenach @rouanw
rouanw.github.io thoughtworks.com