Software is complex. Some aspects of its complexity are essential, others are incidental. In this presentation, I describe some of these aspects of complexity and provide recommendations on how to truly and effectively simplify them.

1. Essen%al & Incidental Complexity of
So7ware
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2. Charles Meigs Oliver Wendell Holmes

3. a fluid, highly empowered team
of skilled people
is our best current offense
against so7ware complexity

4. essen%al

5. incidental

8. essen%al complexity

13. unique elements

15. Fault tolerance
Security
Web App
Project
planning
spreadsheet
Database
User Connec%vity
Friendliness
Availability
Version
Control Project
System DB

16. asymmetric scaling

19. anArray.length
aList.size()
aString.length()
Array.getLength
(Object array)

20. arbitrariness

25. representa%on

26. requirements
staff
tools
development prac%ces
management prac%ces
languages
libraries
hardware
compe%%on

27. change

28. essen%al
unique elements
asymmetric scaling
arbitrariness
representa%on
change

29. incidental complexity

32. planning

33. May 1,1937

34. May 2,1937

35. Fourth state

36. Fourth state

37. refinement

38. Design
Test Manage Analyze
Code

39. Design
Test Manage Analyze
Code

40. Test Manage
Code Design
Analyze

41. organiza%on

42. essen%al incidental
unique elements planning
asymmetric scaling refinement
arbitrariness organiza%on
representa%on
change

44. fluidity

47. skill

48. Build Monitors Customer Showcases
Fishbone diagrams Daily Standups

49. transparency

50. aspects of agility
fluidity
skill
transparency

52. Image Credits
• Oliver Wendell Holmes: hZp://www.ts4.com/Quotes/Pictures/OliverWendellHolmesSr.jpg
• Charles Meigs: hZp://en.wikipedia.org/wiki/File:Charles_Delucena_Meigs_(1792_‐1869)_bw2.jpg
• Shoelace hZp://professorcharleshuman.wordpress.com/2009/09/22/how‐to‐%e‐a‐shoelace/
• Jennifer Stemack: hZp://www.child‐amputee.net/Mentors/Jenny/jenny.htm
• Glass half‐full: hZp://www.thehealthword.com/images/pouring‐water.jpg
• Mezquita: hZp://terre.sans.fron%ere.free.fr/page_a_voir_a_faire/a_voir_a_faire_images/mosquee_cordoba_1.jpg
• Fern leaves: hZp://www.pbase.com/kelvinphoto/image/63951731.jpg
• Robert Frost’s poem: hZp://thebuZerflydiaries.wordpress.com/2009/07/13/stopping‐by‐woods/
• Nau%lus shell: hZp://www.world‐mysteries.com/illusions/nau%lus_flickr.jpg
• Water molecule: : hZp://www.globalwarmingart.com/images/8/85/Water_Molecule_Formula.png
• User stories: hZp://www.fabrice‐aimek.fr/dotclear/public/user_stories.jpg
• Flow chart: hZp://www.movimiento.nl/images/Func%onalInterac%onAnalysis.gif
• Class diagram: hZp://java.freehep.org/freehep1.x/yappi/diagrams/ClassDiagram.gif
• Performance profile: hZp://www.burningdoor.com/eric/images/jprofiler‐sampler.png
• Klein boZle: hZp://www.sciencemuseum.org.uk/images/object_images/535x535/10314758.jpg
• GanZ chart: hZp://www.romankoch.ch/capslock/ganZ.htm
• Dominoes: hZp://www.chicagometroarearealestate.com/images/Dominos1.jpg
• Guernica 1, 2 & 3: hZp://www.mar%nries.com/ar%cle2007AG.htm
• Guernica 4: hZp://allencentre.wikispaces.com/file/view/guernica.jpg/34409799
• Agile team room: Saleem Siddiqui
• CTRL key: : hZp://www.aprilhoff.info/Images/Computers/Ctrl‐02.gif
• Sand ar%sts: hZp://michaelmyers.biz/images/sandpain%ng.jpg

53. thank you
saleem @ thoughtworks . com
www.thoughtworks.com