1) The document discusses myths, truths, and wishful thinking around workflow systems. It addresses 5 common myths: that visual tools are the only way to do workflow; workflow should run all application logic; domain experts can easily change workflows at runtime; declarative development is always easier than traditional development; and simple workflows can be built in 100 lines of code. 2) For each myth, it provides a counterargument or "truth". For example, many code-first solutions offer workflow benefits without steep learning curves. Workflow is best for long-running or complex processes, not all logic. Changing workflows at runtime requires diligence. Declarative development has tradeoffs compared to traditional approaches. Simple workflows can unravel with complexity.

1. Workflow Systems Myths, Truths and Wishful Thinking Brandon Satrom Chief Architect, Thought Ascent brandon.satrom@thoughtascent.com www.userinexperience.com

2. Copyright 2009, Thought Ascent, Inc About Me - In Six Words Opinionated Architect. Often wrong. Continually improving.

3. Long-time Microsoft developer Former Enterprise Architect Alt.Net guy, but still nice President, IASA Austin Copyright 2009, Thought Ascent, Inc Worth mentioning?

4. Experience with vendor WF tools Experience with BizTalk (2002+) Recently built a successful production implementation using WF 3.5 See that “opinionated architect” comment. Copyright 2009, Thought Ascent, Inc What qualifies me to talk about Workflow…

5. Copyright 2009, Thought Ascent, Inc So what is “Workflow” anyway?

6. Copyright 2009, Thought Ascent, Inc A workflow is a depiction of a sequence of operations, declared as work of a person, a group of persons, an organization of staff, or one or more simple or complex mechanisms. Workflow may be seen as any abstraction of real work, segregated in workshare, work split or other types of ordering. For control purposes, workflow may be a view on real work under a chosen aspect, thus serving as a virtual representation of actual work. The flow being described often refers to a document that is being transferred from one step to another. – from http://en.wikipedia.org/wiki/Workflow

7. Copyright 2009, Thought Ascent, Inc How about something simpler?

8. The coordination of work in a “system” Copyright 2009, Thought Ascent, Inc

9. Copyright 2009, Thought Ascent, Inc Got it. So then what’s a “Workflow System?”

10. Perhaps… An application that assists in the definition and/or execution and/or management of workflows Copyright 2009, Thought Ascent, Inc

11. Copyright 2009, Thought Ascent, Inc That sounds too similar to a “normal” system. What’s the difference?

12. How a workflow system differs from a traditional program In theory, at least… Copyright 2009, Thought Ascent, Inc

13. Declarative Copyright 2009, Thought Ascent, Inc

14. Persistent Copyright 2009, Thought Ascent, Inc External Stimulus Persistence Store

15. Dynamic Copyright 2009, Thought Ascent, Inc Business Change Activity F Divert to new activity

16. Configurable Copyright 2009, Thought Ascent, Inc Activity D Activity E Rules Store

17. Centrally Defined… Copyright 2009, Thought Ascent, Inc

18. … though not necessarily visual. Copyright 2009, Thought Ascent, Inc static SessionSaga() { Define(() => { Initially( When(NewSession) .Then((saga, message) => saga.NewSessionStarted(message)) .TransitionTo(SessionActive) ); During(SessionActive, When(FeedbackCheckRequested) .Then((saga, message) => saga.CheckForFeedback(message)) When(new Timer() .StartOn(session.Start) .RunAtInterval(session.CheckInterval) .Until(session.End)) .Then((saga, message) => saga.CheckForFeedback(message)) When(SessionComplete) .Then((saga, message) => saga.SessionEnded(message)) .Complete() ); });}

19. Copyright 2009, Thought Ascent, Inc Ok, I get it. So why are we still doing this presentation?

20. Copyright 2009, Thought Ascent, Inc Workflow has a PR problem…

21. Copyright 2009, Thought Ascent, Inc There seem to be two sides…

22. Copyright 2009, Thought Ascent, Inc …who can’t (or won’t) get along.

23. The “Workflow will Save us all” side Copyright 2009, Thought Ascent, Inc

24. The “Run like you’re on fire” side Copyright 2009, Thought Ascent, Inc

25. Copyright 2009, Thought Ascent, Inc I’d like a third option please.

26. Copyright 2009, Thought Ascent, Inc How about the best of both?

27. Consider both sides of the story…

28. And be a cautious optimist… Copyright 2009, Thought Ascent, Inc

29. There are reasons to get excited about Workflow… Copyright 2009, Thought Ascent, Inc

30. Copyright 2009, Thought Ascent, Inc Visual, Visual, Visual

31. Copyright 2009, Thought Ascent, Inc Clear expression of intent from domain experts…

32. Copyright 2009, Thought Ascent, Inc The Next “Great Leap” in software

33. …and there are reasons to be wary… Copyright 2009, Thought Ascent, Inc

34. Steep-learning curves Copyright 2009, Thought Ascent, Inc

35. Copyright 2009, Thought Ascent, Inc Poor Performance

36. Copyright 2009, Thought Ascent, Inc Sleights of hand and shell-games

37. Copyright 2009, Thought Ascent, Inc Both sides are right … Both sides are wrong….

38. Copyright 2009, Thought Ascent, Inc Right and wrong? How so?

39. Myths, Truths and Wishful Thinking Copyright 2009, Thought Ascent, Inc

40. 1) Visual Workflow Tools are the only way to “do” Workflow Copyright 2009, Thought Ascent, Inc

41. Myth Copyright 2009, Thought Ascent, Inc

42. Is this really easier to comprehend… Copyright 2009, Thought Ascent, Inc

43. Than this? require 'rubygems' require 'statemachine' vending_machine = Statemachine.build do state :waiting do event :dollar, :paid, :activate event :selection, :waiting on_entry :sales_mode on_exit :operation_mode end trans :paid, :selection, :waiting, :release trans :paid, :dollar, :paid, :refund context VendingMachineContext.new end Copyright 2009, Thought Ascent, Inc

44. The Truth Many open-source “code-first” solutions offer most of the benefits of a workflow system without the steep learning curve. Copyright 2009, Thought Ascent, Inc

45. Demo –Workflow with Mass Transit Copyright 2009, Thought Ascent, Inc

46. 2) Workflow should be running all your application logic Copyright 2009, Thought Ascent, Inc

47. Lie Copyright 2009, Thought Ascent, Inc

48. Turn a simple flow… Copyright 2009, Thought Ascent, Inc

49. …into “Spaghetti Flow” Copyright 2009, Thought Ascent, Inc

50. The Truth Workflow systems can be a good choice for managing long-running, complex processes, but don’t yet perform well-enough to handle all your logic. Copyright 2009, Thought Ascent, Inc

51. 3) Domain experts can (and should) easily change workflows at runtime Copyright 2009, Thought Ascent, Inc

52. Copyright 2009, Thought Ascent, Inc

53. Wishful Thinking… Copyright 2009, Thought Ascent, Inc

54. The Truth We don’t change systems at runtime without some diligence. So why would our users? That said. There are models that are more illustrative of reality… Copyright 2009, Thought Ascent, Inc

56. 4) Declarative/Visual App Dev is easier than traditional dev… Copyright 2009, Thought Ascent, Inc

57. Half-Truth Copyright 2009, Thought Ascent, Inc

58. The Truth Where it’s easier: OOB programming constructs (IF, While, etc) Encourages/ Rewards SRP-development Where it’s harder: Visual IDEs slower than code IDEs Testing is hard, if not impossible Refactoring involves more rework than necessary Copyright 2009, Thought Ascent, Inc

59. 5) “I can build a WF system in 100 lines of code” Copyright 2009, Thought Ascent, Inc

60. Wishful Thinking… Copyright 2009, Thought Ascent, Inc

61. The Truth Code-only solutions can address simple scenarios quickly… But tend to unravel when persistence, durability, scale,timed-events, long-running processes, human workflow and other complex issues are introduced. Copyright 2009, Thought Ascent, Inc

62. The Faceplant Application “Social Speaking” Demo: Copyright 2009, Thought Ascent, Inc

63. Copyright 2009, Thought Ascent, Inc Congratulations! You’ve done an excellent job of not telling me what I should do…

64. Open Discussion – When should a Workflow Tool be considered? Copyright 2009, Thought Ascent, Inc

65. When does WF make sense? … Copyright 2009, Thought Ascent, Inc

66. Copyright 2009, Thought Ascent, Inc I think it’s time for the bottom line…

67. There is no simple answer… Only the right tool for the job Copyright 2009, Thought Ascent, Inc

68. The Right Tool for The Job might be… “Roll Your Own” Workflow Use an open-source Bus NServiceBus Mass Transit Simple ServiceBus Use an open-source State management tool Simple State Machine Use Windows WF After you’ve exhausted all other possibilities Copyright 2009, Thought Ascent, Inc

69. Consider a “Workflow System” when: Need a visual, changeable representation Timed-events are key Long-running: Transactions Conversations Services Many, complex processes Economies of scale principle Copyright 2009, Thought Ascent, Inc

70. Don’t start with a workflow system as a solution. Get there by eliminating other options Copyright 2009, Thought Ascent, Inc

71. And pay attention… Software development is changing. Copyright 2009, Thought Ascent, Inc

72. Questions? brandon.satrom@thoughtascent.com www.userinexperience.com Twitter: @thesatch Code and slides available at: http://github.com/bsatrom/WorkflowSystems Copyright 2009, Thought Ascent, Inc

73. Image Credits WF System, InfoWorld http://www.infoworld.com/d/developer-world/product-review-ultimus-jump-starts-bpm-deployment-546?page=0,1 Pinnochio – House of Sims, Flickr http://www.flickr.com/photos/houseofsims/2662410465/ Myth – Mythbusters on Discovery http://dsc.discovery.com/fansites/mythbusters/wallpaper/wallpaper.html Steep Learning Curve – Casual Game Design http://www.casualgamedesign.com/?p=27 Skeptic Guy – Flick http://www.flickr.com/photos/mcleod/3909431214/in/set-72157607796029636 Copyright 2009, Thought Ascent, Inc