Designed Stickiness

NCrafts 2016, Paris

Transcript

1. Designed
   Stickiness
   @mathiasverraes
   

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2. @mathiasverraes
   verraes.net
   Student of Systems
   Meddler of Models
   Labourer of Legacy
   

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4. Let's talk about
   metaphors that stick
   

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5. Great metaphors
   create opportunity
   

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6. ( ... even if it takes a while )
   

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7. «Breakthrough:
   An opportunity opens up
   to transform your software
   into something
   more expressive and versatile
   than you expected.»1
   1 "Domain-Driven Design", Eric Evans, 2004
   

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8. Breakthroughs are often linguistic.
   

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9. Language is not a tool like
   metalworking or writing
   It's how our brains are wired2
   2 "The Language Instinct - How the Mind Creates
   Language", Steven Pinker, 1994
   

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10. Some language is more sticky
    Advertisers learned this
    a long time ago
    

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11. Ceci n'est pas le Ping-Pong.
    

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12. Microservices vs SCS-architecture
    

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13. The optimistic age of OOP
    Objects as a thinking tool4
    Anthropomorphic objects5
    Objects as projections of the mind
    ...
    5 "Object Design: Roles, Responsibilities, and
    Collaborations", Rebecca Wirfs-Brock & Alan McKean,
    2003
    4 "Object Thinking", David West, 2004
    

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14. Mainstream OOP:
    Objects as a way to structure imperative code
    

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15. Logger
    {
    log(...)
    {
    ...
    }
    }
    

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16. Execution in the
    Kingdom of Nouns6
    6 http://steve-yegge.blogspot.be/2006/03/execution-in-
    kingdom-of-nouns.html
    

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17. A healthy obsession
    with language
    

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19. Log
    {
    append(...)
    {
    ...
    }
    }
    

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20. Metaphors as objects
    

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21. «His people are completely literal.
    Metaphors go over his head.»
    

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22. «Nothing goes over my head.
    My reflexes are too fast,
    I would catch it.»
    

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23. Example: Data Matching
    Paying money based on usage of content
    Determine ownership based on matches in data
    

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24. Data sources:
    Own research by employees
    Off shore data cleaning
    Public wiki-style
    Public but curated
    Private, paid
    Direct submissions from individuals
    Agencies representing owners
    

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25. Lots of incentives for fraud
    

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26. Is this our Core Domain?
    ✗ It's just technical data imports
    ⬜
    ⬜
    ⬜
    ⬜
    

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27. Is this our Core Domain?
    ✗ It's just technical data imports
    ✗ Business is not interested
    ⬜
    ⬜
    ⬜
    

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28. Is this our Core Domain?
    ✗ It's just technical data imports
    ✗ Business is not interested
    ✔ Money changing hands
    ⬜
    ⬜
    

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29. Is this our Core Domain?
    ✗ It's just technical data imports
    ✗ Business is not interested
    ✔ Money changing hands
    ✔ The code you keep secret
    ⬜
    

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30. Is this our Core Domain?
    ✗ It's just technical data imports
    ✗ Business is not interested
    ✔ Money changing hands
    ✔ The code you keep secret
    ✔ Oldest code in the system
    

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31. Event Storming
    

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32. Temporality
    The quality of data
    changes over time,
    based on who changes it
    

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33. Missing concept:
    Matching Data
    =>
    ?
    

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34. Missing concept:
    Matching Data
    =>
    Earning Trust
    

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35. Trust as a sticky metaphor
    Adopted by business
    

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36. Adopted into Ubiquitous Language
    

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37. The business started getting
    interested and involved
    

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38. What if Trust was a tangible thing
    in our domain model?
    

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39. Trust as a Value Object
    

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40. Trust can be passed around
    

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41. Trust attracts behaviour
    

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42. Strategies for changing Trust
    Event-based workflows
    

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43. 0 5 10
    

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44. A Trust Arithmetic
    Invented by the business
    0 5 10
    Group
    (closure, associativity, identity, invertibility)
    

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45. «Habitable software (...)
    enables people to understand
    its construction and intentions
    and to change it
    comfortably and confidently.»7
    Programmers are not the only
    ones inhabiting our systems
    7 "Patterns of Software", Richard P. Gabriel, 1996
    

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46. Example:
    Phone call bill rating
    

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47. Price per minute, price after the 60th minute
    Bundles: Credit minutes, lower rates
    Subscriptions: recurring bundles
    Promotions and incentives
    End of month transfers, expiries
    Flexible rating strategies in different markets
    

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48. "It's just an algorithm"
    

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49. Missing Metaphor:
    Buckets
    

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52. Mental Model
    ~
    Visual Model
    ~
    Implementation Model
    

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53. New opportunity:
    Long lead time to change pricing
    =>
    Lively experimentation with pricing
    

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54. System Metaphors (XP)
    are too ambitious
    

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55. Metaphors
    are not specifications
    

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56. Small, local metaphors
    

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57. How to find metaphors?
    It's not magic, it's awareness
    

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58. Modelling
    is spending time
    with the problem
    

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59. Obsess over language
    

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60. Visualise different models
    (structural, temporal, spatial...)
    

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61. Grasp the underlying principles of
    the problem and the domain
    

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62. «[A paradigm change]
    can happen in a millisecond.
    All it takes is a click in the mind,
    a falling of scales from the eyes,
    a new way of seeing.»8
    8 "Thinking in Systems", Donella H. Meadows, 2008
    

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63. Thank you —
    verraes.net
    @mathiasverraes
    verraes.net/workshops
    dddeurope.com
    

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