Réconcilier architecture logicielle & problématiques métiers : une introduction au Domain Driven Design – Blend Web Mix 2021

Avez-vous déjà vécu le fait qu’un petit changement dans le métier déclenche une apocalypse dans le code du logiciel ? Ce genre de symptômes sont souvent le signe que l’architecture du logiciel et le métier de l’entreprise ne sont plus alignés.
Dans cette conférence nous verrons comment permettre aux développeurs d’exprimer les besoins métiers au sein de l’architecture du logiciel afin d’éviter toute une catégorie de problèmes. Problèmes à l’origine d’effets de bords particulièrement dangereux et qui empêchent une politique de refactoring efficace.
Cette présentation des aspects stratégiques de la conception pilotée par le domaine (Domain Driven Design) n’est pas une présentation technique, elle s’adresse ainsi à la fois aux développeurs mais également à l’ensemble des parties prenantes liées à la conception du logiciel.

Transcript

1. www.lilobase.me
   The strategies
   behind DDD
   @lilobase
   #BlendWebMix
   sundayapp.com
   

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2. Let’s start a new project !
   

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3. Sprint Zero
   

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4. Sprint Zero
   Angular
   or React ?
   

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5. Sprint Zero
   Java or C# ?
   Angular
   or React ?
   

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6. Sprint Zero
   Java or C# ?
   Spring Boot or
   Quarkus ?
   Angular
   or React ?
   

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7. Sprint Zero
   Java or C# ?
   Spring Boot or
   Quarkus ?
   Kafka
   or Redis ?
   Angular
   or React ?
   

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8. Sprint Zero
   Java or C# ?
   Spring Boot or
   Quarkus ?
   Kafka
   or Redis ?
   Microservices
   or Monolith ?
   Angular
   or React ?
   

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9. Sprint Zero
   Java or C# ?
   Spring Boot or
   Quarkus ?
   Kafka
   or Redis ?
   Microservices
   or Monolith ?
   Kubernetes
   or Nomad ?
   Angular
   or React ?
   

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10. Look, at our spring
    boot application with
    Kafka deployed on a K8S
    Cluster
    Sprint Zero
    

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11. Look, at our spring
    boot application with
    Kafka deployed on a K8S
    Cluster
    They know nothing
    about the project’s business
    domain
    Sprint Zero
    

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12. Look, at our spring
    boot application with
    Kafka deployed on a K8S
    Cluster
    They know nothing
    about the project’s business
    domain
    …
    Sprint Zero
    

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13. Java or C# ?
    Spring Boot or
    Quarkus ?
    Kafka
    or Redis ?
    Microservices
    or Monolith ?
    Kubernetes
    or Nomad ?
    Angular
    or React ?
    These issues address only
    the solution
    

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14. But not the problem
    What should we do ?
    

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15. But not the problem
    What should we do ?
    …
    

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16. Spring Boot or
    Quarkus ?
    Kafka
    or Redis ?
    Microservices
    or Monolith ?
    Kubernetes
    or Nomad ?
    Angular
    or React ?
    And that's why we
    
    
    are seen as technical expert
    Java or C# ?
    

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17. solution
    problem
    What should we do ?
    How are we going to do it ?
    

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18. solution
    problem
    What should we do ?
    How are we going to do it ?
    It is an important discussion to have
    

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19. solution
    problem
    What should we do ?
    How are we going to do it ?
    It is an important discussion to have
    But only after we've
    fi
    gured out
    

    what to do
    

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20. DDD is all about
    Alignment
    What should we do ?
    How are we going to do it ?
    

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21. DDD is all about
    Alignment
    What should we do ?
    How are we going to do it ?
    

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22. DDD is all about
    Alignment
    What should we do ?
    How are we going to do it ?
    

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23. « Donnez un marteau à un enfant, et il
    trouvera que tout a besoin d'être
    martelé. »
    – Abraham Kaplan
    

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24. « On fait passer les
    besoins de la base
    de donnée avant
    ceux des utilisateurs
    ce qui donne des
    expériences assez
    pourries »
    – @WalterStephanie
    

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25. www.lilobase.me
    DDD is all about
    Understanding
    @lilobase
    

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26. Domains & Subdomains
    Business Domain discovery
    THE software
    

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27. Domain Mapping
    Business Domain Classi
    fi
    cation
    Authoring
    
    
    &
    
    
    Publishing
    Customer Care
    Printing &
    
    
    Supply Chain
    Retail Store
    

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28. Domain Mapping
    Business Domain Classi
    fi
    cation
    Authoring
    
    
    &
    
    
    Publishing
    Customer Care
    Printing &
    
    
    Supply Chain
    Retail Store
    You need to acknowledge the fact that
    you have several domains
    

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29. Domain Mapping
    Business Domain Classi
    fi
    cation
    Authoring
    
    
    &
    
    
    Publishing
    Customer Care
    Printing &
    
    
    Supply Chain
    Retail Store
    

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30. Domain Mapping
    Business Domain Classi
    fi
    cation
    Authoring
    
    
    &
    
    
    Publishing
    Customer Care
    Printing &
    
    
    Supply Chain
    Retail Store
    Only one VP should be
    
    
    angry at a time
    

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31. Domain Mapping
    Business Domain Classi
    fi
    cation
    Authoring
    
    
    &
    
    
    Publishing
    Customer Care
    Printing &
    
    
    Supply Chain
    Retail Store
    These are neither Bounded
    Contexts nor Microservices
    

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32. Domain Mapping
    Business Domain Classi
    fi
    cation
    Authoring
    
    
    &
    
    
    Publishing
    Customer Care
    Printing &
    
    
    Supply Chain
    Retail Store
    These are your domains
    

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33. Domain Mapping
    Business Domain Classi
    fi
    cation
    Authoring
    
    
    &
    
    
    Publishing
    Customer
    Care
    Printing &
    
    
    Supply Chain
    Online Retail Store
    Payment
    processor
    Catalogue Invoicing
    

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34. Domain Mapping
    Business Domain Classi
    fi
    cation
    Authoring
    
    
    &
    
    
    Publishing
    Customer
    Care
    Printing &
    
    
    Supply Chain
    Online Retail Store
    Payment
    processor
    Catalogue Invoicing
    Your domains contain domains
    

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35. Supporting
    Subdomain
    Generic
    Subdomain
    Core
    (sub)Domain
    Key differentiator
    Domains & Subdomains
    Business Domain Classi
    fi
    cation
    

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36. Supporting
    Subdomain
    Generic
    Subdomain
    Core
    (sub)Domain
    Key differentiator
    Domains & Subdomains
    Business Domain Classi
    fi
    cation
    Critical to the
    

    organization’s success
    

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37. Supporting
    Subdomain
    Generic
    Subdomain
    Core
    (sub)Domain
    Key differentiator
    Domains & Subdomains
    Business Domain Classi
    fi
    cation
    Essential to the
    

    organization’s success
    Critical to the
    

    organization’s success
    

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38. Supporting
    Subdomain
    Generic
    Subdomain
    Core
    (sub)Domain
    Key differentiator
    Domains & Subdomains
    Business Domain Classi
    fi
    cation
    Essential to the
    

    organization’s success
    Required for the
    

    organization’s success
    Critical to the
    

    organization’s success
    

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39. Domain Mapping
    Business Domain Classi
    fi
    cation
    Authoring
    Plateform
    Publishing &
    Printing
    Inventory
    Management
    Payment
    Processor
    Catalogue
    Invoicing
    Shipping
    Order
    Processing
    Proofreading
    

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40. Domains & Subdomains
    Business Domain Classi
    fi
    cation
    Authoring
    Plateform
    Inventory
    Management
    Shipping
    Payment
    Processor
    Catalogue
    Invoicing
    Order
    Processing
    Publishing &
    Printing
    Proofreading
    

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41. Domains & Subdomains
    Business Domain Classi
    fi
    cation
    Authoring
    Plateform
    Inventory
    Management
    Payment
    Processor
    Catalogue
    Invoicing
    Shipping
    Order
    Processing
    Publishing &
    Printing
    Proofreading
    

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42. Domains & Subdomains
    Business Domain Classi
    fi
    cation
    Authoring
    Plateform
    Inventory
    Management
    Payment
    Processor
    Catalogue
    Invoicing
    Each business context is speci
    fi
    c
    Shipping
    Order
    Processing
    Publishing &
    Printing
    Proofreading
    

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43. Authoring
    Plateform
    Domains’ Connexion
    Reveal Business Relationships
    Inventory
    Management
    Shipping
    Catalogue
    Invoicing
    Order
    Processing
    Payment
    Processor
    Publishing &
    Printing
    Proofreading
    

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44. Authoring
    Plateform
    Domains’ Connexion
    Reveal Business Relationships
    Inventory
    Management
    Shipping
    Catalogue
    Invoicing
    Order
    Processing
    Payment
    Processor
    It can highlight signi
    fi
    cant
    

    sub-domain
    Publishing &
    Printing
    Proofreading
    

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45. Authoring
    Plateform
    Domains’ Connexion
    Reveal Business Relationships
    Inventory
    Management
    Shipping
    Catalogue
    Invoicing
    Order
    Processing
    Payment
    Processor
    It can highlight signi
    fi
    cant
    

    sub-domain
    Publishing &
    Printing
    Proofreading
    

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46. www.lilobase.me
    DDD is all about
    Context
    @lilobase
    

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47. From Problem to Solution
    Authoring
    Plateform
    Publishing
    & Printing
    Inventory
    Management
    Shipping
    Payment
    Processor
    Catalogue
    Invoicing
    Order
    Processing
    Proofreading
    

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48. From Problem to Solution
    Authoring
    Plateform
    Publishing
    & Printing
    Inventory
    Management
    Shipping
    Payment
    Processor
    Catalogue
    Invoicing
    Order
    Processing
    problem
    solution
    Payment
    processor
    Invoicing
    Order
    Processing
    Shipping
    Authoring
    Plateforme
    Inventory
    Management
    Catalogue
    Publishing
    Proofreading
    Proofreading
    Inventory E-commerce platform
    Authoring
    Publishing
    

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49. Domains & Subdomains
    Development Strategy
    Supporting
    Subdomain
    Generic
    Subdomain
    Core
    (sub)Domain
    Key differentiator
    

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50. Domains & Subdomains
    Development Strategy
    Supporting
    Subdomain
    Generic
    Subdomain
    Core
    (sub)Domain
    In-House development
    

    with Your best teams
    Key differentiator
    

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51. Domains & Subdomains
    Development Strategy
    Supporting
    Subdomain
    In-House development with
    

    external support if possible
    Generic
    Subdomain
    Core
    (sub)Domain
    In-House development
    

    with Your best teams
    Key differentiator
    

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52. Domains & Subdomains
    Development Strategy
    Supporting
    Subdomain
    In-House development with
    

    external support if possible
    Generic
    Subdomain
    Outsourcing is an option
    Core
    (sub)Domain
    In-House development
    

    with Your best teams
    Key differentiator
    

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53. Domains & Subdomains
    Development Strategy
    Supporting
    Subdomain
    Generic
    Subdomain
    Core
    (sub)Domain
    Key differentiator
    

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54. Domains & Subdomains
    Development Strategy
    Supporting
    Subdomain
    Generic
    Subdomain
    Core
    (sub)Domain
    Custom-made software
    
    
    High Cost & Quality
    Key differentiator
    

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55. Domains & Subdomains
    Development Strategy
    Supporting
    Subdomain
    Customized Off The Shelf Software
    

    is an option
    Generic
    Subdomain
    Core
    (sub)Domain
    Custom-made software
    
    
    High Cost & Quality
    Key differentiator
    

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56. Domains & Subdomains
    Development Strategy
    Supporting
    Subdomain
    Customized Off The Shelf Software
    

    is an option
    Generic
    Subdomain
    Try to
    fi
    nd Off The Shelf solution
    
    
    Cost saving opportunities
    Core
    (sub)Domain
    Custom-made software
    
    
    High Cost & Quality
    Key differentiator
    

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57. From Problem to Solution
    Payment
    processor
    Invoicing
    Order
    Processing
    Shipping
    Authoring
    Plateforme
    Inventory
    Management
    Catalogue
    Publishing
    Proofreading
    Inventory E-commerce platform
    Authoring
    Publishing
    Authoring
    Plateform
    Publishing
    & Printing
    Inventory
    Management
    Shipping
    Payment
    Processor
    Catalogue
    Invoicing
    Order
    Processing
    Proofreading
    

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58. From Problem to Solution
    Inventory E-commerce platform
    Authoring
    Authoring
    Plateforme Publishing
    Catalogue
    Publishing
    Proofreading
    Authoring
    Plateform
    Publishing
    & Printing
    Inventory
    Management
    Shipping
    Payment
    Processor
    Catalogue
    Invoicing
    Order
    Processing
    Proofreading
    

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59. From Problem to Solution
    Business Domain & Architecture alignment
    Inventory E-commerce
    
    
    platform
    Authoring
    Authoring
    Plateforme Publishing
    Catalogue
    Publishing
    Proofreading
    

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60. From Problem to Solution
    Business Domain & Architecture alignment
    Inventory E-commerce
    
    
    platform
    Authoring
    Authoring
    Plateforme Publishing
    Catalogue
    Publishing
    Proofreading
    These are your bounded contexts
    

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61. Inventory E-commerce
    
    
    platform
    Authoring
    Publishing
    « Team assignments are the
    fi
    rst
    draft of the architecture »
    – Michael Nygard
    

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62. Inventory E-commerce
    
    
    platform
    Authoring
    Publishing
    Align your teams with your
    bounded context
    « Team assignments are the
    fi
    rst
    draft of the architecture »
    – Michael Nygard
    

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63. P
    Authoring
    Publishing
    E-commerce
    Stripe
    ShipMonk Shopify
    Context Mapping
    Relationship Hierarchy
    OHS
    OHS
    ACL
    OHS
    C/S
    

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64. Authoring
    Publishing
    E-commerce
    Specific Architecture style
    You don’t need one architectural style
    ES
    CQRS
    CRUD ?
    Stripe
    ShipMonk Shopify
    

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65. Authoring
    Publishing
    E-commerce
    Specific Architecture style
    You don’t need one architectural style
    Beware of the CRUD
    ES
    CQRS
    CRUD ?
    Stripe
    ShipMonk Shopify
    

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66. Stripe
    Still no microservices
    Bounded Context ≠ Deployment units
    ShipMonk
    Authoring
    Publishing
    E-commerce
    Shopify
    Deployment Unit
    

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67. Deployment Unit
    Stripe
    Still no microservices
    Bounded Context ≠ Deployment units
    ShipMonk
    Authoring
    Publishing
    E-commerce
    Shopify
    Deployment Unit
    

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68. Domains are not immutable
    Understanding is a never-ending process
    Stripe
    ShipMonk
    Authoring
    Publishing
    E-commerce
    Shopify
    

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69. Domains are not immutable
    Understanding is a never-ending process
    Stripe
    ShipMonk
    Authoring
    Publishing
    E-commerce
    Shopify
    Printing
    

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70. www.lilobase.me
    DDD is all about
    Boundaries
    @lilobase
    

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71. Semantic Boundaries
    Between BC meaning are different
    Authoring Publishing
    Book
    Chapter
    Chapter
    

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72. Semantic Boundaries
    Between BC meaning are different
    Authoring Publishing
    Book
    Chapter
    Chapter
    What
    happens if
    the author
    revises his
    book?
    

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73. Semantic Boundaries
    Between BC meaning are different
    Authoring Publishing
    Book
    Chapter
    Chapter
    They are not the same book
    What
    happens if
    the author
    revises his
    book?
    

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74. Semantic Boundaries
    Between BC meaning are different
    Chapter Author
    Book
    Reviews
    Release
    Catalogue
    

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75. Semantic Boundaries
    Between BC meaning are different
    Chapter
    This is why you must start by understand
    strategically your domain
    Author
    Book
    Reviews
    Release
    Catalogue
    

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76. Semantic Boundaries
    Between BC meaning are different
    Authoring Publishing
    Book
    Chapter
    Chapter
    Book
    Chapter
    Chapter
    

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77. Semantic Boundaries
    Between BC meaning are different
    Authoring Publishing
    Book
    Chapter
    Chapter
    Book
    Chapter
    Chapter
    Inside a
    Bounded
    Context,
    

    Don’t
    

    Repeat
    

    Yourself
    

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78. Semantic Boundaries
    Between BC meaning are different
    Authoring Publishing
    Book
    Chapter
    Chapter
    Book
    Chapter
    Chapter
    Inside a
    Bounded
    Context,
    

    Don’t
    

    Repeat
    

    Yourself
    Between
    Bounded
    Context,
    

    Write
    

    Everything
    

    Twice
    

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79. Don’t cross them
    Between BC meaning are different
    Authoring Publishing
    Author
    Reviews
    Author
    Book Book
    Release
    

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80. Don’t cross them
    Between BC meaning are different
    Authoring Publishing
    Author
    Reviews
    Author
    Book Book
    Release
    

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81. Don’t cross them
    Between BC meaning are different
    Authoring Publishing
    Author
    Reviews
    Author
    Book Book
    Release
    Never create relationships
    between entities from two BC
    

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82. Don’t cross them
    Between BC meaning are different
    Authoring Publishing
    Book Book
    Release
    Author
    Author
    Reviews
    

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83. Don’t cross them
    Between BC meaning are different
    Authoring Publishing
    Book Book
    Release
    Author
    Author
    Reviews
    

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84. Don’t cross them
    Between BC meaning are different
    Authoring Publishing
    Book Book
    Release
    Author
    Author
    Reviews
    This is exactly the same
    

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85. Don’t cross them
    Between BC meaning are different
    Authoring Publishing
    Book Book
    Release
    Author
    Author
    Reviews
    API API
    

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86. Same for Events
    Between BC meaning are different
    Authoring Publishing
    Event
    

    Bus
    Book Book
    Release
    Author
    Author
    Reviews
    

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87. Same for Events
    Between BC meaning are different
    Authoring Publishing
    Event
    

    Bus
    Book Book
    Release
    Author
    Author
    Reviews
    

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88. Same for Events
    Between BC meaning are different
    Authoring Publishing
    This is exactly the same
    Event
    

    Bus
    Book Book
    Release
    Author
    Author
    Reviews
    

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89. Same for Events
    Between BC meaning are different
    Authoring Publishing
    Event
    

    Bus
    Book Book
    Release
    Author
    Author
    Reviews
    Translator Translator
    

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90. Transactional Boundaries
    Protect your integrity
    Authoring
    Book
    Chapter
    Chapter
    Chapter
    Statistics
    

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91. Transactional Boundaries
    Protect your integrity
    Authoring
    Book
    Chapter
    Chapter
    Chapter
    Statistics
    Inside your
    bounded
    Context
    

    live
    

    Entities
    

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92. Transactional Boundaries
    Protect your integrity
    Authoring
    Book
    Chapter
    Chapter
    Chapter
    Statistics
    Inside your
    bounded
    Context
    

    live
    

    Entities
    They are
    grouped in
    Aggregates
    

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93. Transactional Boundaries
    Protect your integrity
    Book
    Chapter
    Chapter
    Chapter
    Statistics
    

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94. Transactional Boundaries
    Protect your integrity
    Book
    Chapter
    Chapter
    Chapter
    Statistics
    Inside an
    aggregate,
    Entities
    

    share the
    same
    lifecycle
    

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95. Transactional Boundaries
    Protect your integrity
    Book
    Chapter
    Chapter
    Chapter
    Statistics
    They are
    retrieved
    and
    persisted
    

    as a whole
    Inside an
    aggregate,
    Entities
    

    share the
    same
    lifecycle
    

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96. Transactional Boundaries
    Protect your integrity
    Book
    Chapter
    Chapter
    Chapter
    Statistics
    

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97. Transactional Boundaries
    Protect your integrity
    Book
    Chapter
    Chapter
    Chapter
    Statistics
    All
    interactions
    are done
    through the
    Aggregate
    Root
    

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98. Transactional Boundaries
    Protect your integrity
    Book
    Chapter
    Chapter
    Chapter
    Statistics
    Who
    ensures the
    aggregate
    integrity
    All
    interactions
    are done
    through the
    Aggregate
    Root
    

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99. Transactional Boundaries
    Protect your integrity
    Book
    Chapter
    Chapter
    Chapter
    Statistics
    Who
    ensures the
    aggregate
    integrity
    All
    interactions
    are done
    through the
    Aggregate
    Root
    Write a new chapter
    

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100. Transactional Boundaries
     Protect your integrity
     Book
     Chapter
     Chapter
     Chapter
     Statistics
     

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101. Transactional Boundaries
     Protect your integrity
     Book
     Chapter
     Chapter
     Chapter
     Statistics
     Write a new chapter
     Chapter
     

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102. Transactional Boundaries
     Protect your integrity
     Book
     Chapter
     Chapter
     Chapter
     Statistics
     Write a new chapter
     Chapter
     

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103. Transactional Boundaries
     Protect your integrity
     Book
     Chapter
     Chapter
     Chapter
     Statistics
     Write a new chapter
     Chapter
     Inconsistency
     

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104. Transactional Boundaries
     Protect your integrity
     Book
     Chapter
     Chapter
     Chapter
     Statistics
     Author
     

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105. Transactional Boundaries
     Protect your integrity
     Book
     Chapter
     Chapter
     Chapter
     Statistics
     But don’t
     put to much
     in it
     Author
     

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106. Transactional Boundaries
     Protect your integrity
     Book
     Chapter
     Chapter
     Chapter
     Statistics
     But don’t
     put to much
     in it
     Author
     What
     happens if
     we delete
     the book ?
     

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107. Transactional Boundaries
     Protect your integrity
     Book
     Chapter
     Chapter
     Chapter
     Statistics
     But don’t
     put to much
     in it
     Author
     What
     happens if
     we delete
     the book ?
     They must share the same lifecycle
     

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108. Transactional Boundaries
     Protect your integrity
     Book
     Chapter
     Chapter
     Chapter
     Statistics
     Author
     reference
     Author
     Id
     

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109. Designing Boundaries
     Protect your domain
     Printing Team
     Book
     Chapter
     Chapter
     Chapter
     Release
     API
     Publishing Team
     

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110. Designing Boundaries
     Protect your domain
     Printing Team
     We need printing
     margin
     Book
     Chapter
     Chapter
     Chapter
     Release
     API
     Publishing Team
     

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111. Designing Boundaries
     Protect your domain
     Printing Team
     We need printing
     margin
     Book
     Chapter
     Chapter
     Chapter
     Release
     Printing
     margin
     API
     Publishing Team
     

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112. Designing Boundaries
     Protect your domain
     Printing Team
     We need printing
     margin
     Book
     Chapter
     Chapter
     Chapter
     Release
     We need the
     colorimetric pro
     fi
     le
     Printing
     margin
     API
     Publishing Team
     

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113. Designing Boundaries
     Protect your domain
     Printing Team
     We need printing
     margin
     Book
     Chapter
     Chapter
     Chapter
     Release
     We need the
     colorimetric pro
     fi
     le
     Printing
     margin
     Colorimetric
     pro
     fi
     le
     API
     Publishing Team
     

     View Slide

114. Designing Boundaries
     Protect your domain
     API
     We need printing
     margin
     Book
     Chapter
     Chapter
     Chapter
     Release
     We need the
     colorimetric pro
     fi
     le
     Printing
     margin
     Colorimetric
     pro
     fi
     le
     Domain Leakage
     Publishing Team Printing Team
     

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115. Designing Boundaries
     Protect your domain
     API
     We need printing
     margin
     Book
     Chapter
     Chapter
     Chapter
     Release
     We need the
     colorimetric pro
     fi
     le
     Printing
     margin
     Colorimetric
     pro
     fi
     le
     Domain Leakage
     Publishing Team Printing Team
     

     View Slide

116. Designing Boundaries
     Protect your domain
     Publishing Team Printing Team
     Publishing
     API
     Book
     

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117. Designing Boundaries
     Protect your domain
     Publishing Team Printing Team
     Publishing
     API
     Book
     Printing API
     

     View Slide

118. Designing Boundaries
     Protect your domain
     Publishing Team Printing Team
     Publishing
     API
     We need
     printing margin
     Book
     Printing API
     

     View Slide

119. Designing Boundaries
     Protect your domain
     Publishing Team Printing Team
     Publishing
     API
     We need
     printing margin
     Book
     Printing
     margin
     Printing API
     

     View Slide

120. Designing Boundaries
     Protect your domain
     Publishing Team Printing Team
     Publishing
     API
     We need
     printing margin
     Book
     We need the
     colorimetric
     pro
     fi
     le
     Printing
     margin
     Printing API
     

     View Slide

121. Designing Boundaries
     Protect your domain
     Publishing Team Printing Team
     Publishing
     API
     We need
     printing margin
     Book
     We need the
     colorimetric
     pro
     fi
     le
     Printing
     margin
     Colorimetric
     pro
     fi
     le
     Printing API
     

     View Slide

122. Designing Boundaries
     Protect your domain
     Publishing Team Printing Team
     Publishing
     API
     We need
     printing margin
     Book
     We need the
     colorimetric
     pro
     fi
     le
     Printing
     margin
     Colorimetric
     pro
     fi
     le
     Printing API
     We discovered the need
     

     for an ACL
     

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123. www.lilobase.me
     DDD is all about
     Behavior
     @lilobase
     

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124. CRUD don’t express behavior
     It blinds you from the business perspective
     UPDATE address
     Relocation Mistake correction
     

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125. CRUD don’t express behavior
     It blinds you from the business perspective
     UPDATE address
     Relocation Mistake correction
     

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126. CRUD don’t express behavior
     It blinds you from the business perspective
     Relocation Mistake correction
     

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127. Data oriented programming
     It obfuscates your code
     – Mathias Verraes
     $order->setStatus('paid')
     ;
     
     $order->setPaidAmount(120)
     ;
     
     $order->setPaidCurrency('EUR')
     ;
     
     $order->setCustomer($customer);
     

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128. Data oriented programming
     It obfuscates your code
     – Mathias Verraes
     $order->pay()
     ;
     
     

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129. Data oriented programming
     It obfuscates your code
     $money = new Money(120, new Currency(‘EUR'))
     ;
     
     $order->setPaidMoney($money);
     – Mathias Verraes
     $order->pay()
     ;
     
     

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130. Data oriented programming
     It obfuscates your code
     $money = new Money(120, new Currency(‘EUR'))
     ;
     
     $order->pay($customer, $money);
     – Mathias Verraes
     

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131. Data oriented programming
     It obfuscates your code
     $money = new Money(120, new Currency(‘EUR'))
     ;
     
     $order->pay($customer, $money);
     – Mathias Verraes
     $customer->pay($order, $money)
     ;
     
     

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132. Data oriented programming
     It obfuscates your code
     – Mathias Verraes
     $customer->pay($order, $money)
     ;
     
     $order->setStatus('paid')
     ;
     
     $order->setPaidAmount(120)
     ;
     
     $order->setPaidCurrency('EUR')
     ;
     
     $order->setCustomer($customer);
     

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133. Task Based UI
     Your customer’s need isn’t to
     fi
     ll out forms
     

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134. Users don’t need to fill out forms
     

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135. Users don’t need to fill out forms
     

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136. www.lilobase.me
     DDD is all about
     Compassion
     @lilobase
     

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137. A A
     A
     Ubiquitous language
     Stakeholders & Team Alignement
     Dev Domain
     

     Expert
     Dev
     

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138. A A
     A
     Ubiquitous language
     Stakeholders & Team Alignement
     Dev Domain
     

     Expert
     Dev
     

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139. A A
     A
     Ubiquitous language
     Stakeholders & Team Alignement
     Dev Domain
     

     Expert
     Dev
     

     View Slide

140. A A
     A
     Ubiquitous language
     Stakeholders & Team Alignement
     Dev Domain
     

     Expert
     Dev
     

     View Slide

141. A A
     A
     not « just » a glossary
     Ubiquitous language
     Stakeholders & Team Alignement
     Dev Domain
     

     Expert
     Dev
     

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142. A A
     A
     not « just » a glossary
     Ubiquitous language
     Stakeholders & Team Alignement
     Dev Domain
     

     Expert
     Dev
     

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143. Ubiquitous language
     Each BC has its own
     Authoring Publishing
     A A
     

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144. Ubiquitous language
     Each BC has its own
     Authoring Publishing
     A A
     A A
     

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145. Ubiquitous language
     Each BC has its own
     Authoring Publishing
     A A
     A A
     

     View Slide

146. Ubiquitous language
     Each BC has its own
     Authoring Publishing
     A A
     A A
     

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147. Ubiquitous language
     Each BC has its own
     Authoring Publishing
     A A
     A A
     It is a common cause of
     miscommunication
     

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148. Pair Programing
     The best way to share a domain understanding
     Dev
     

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149. Pair Programing
     The best way to share a domain understanding
     Dev Domain
     

     Expert
     

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150. Know your users
     They might not be who you think they are
     Dev Domain
     

     Expert
     Product
     

     Owner
     Customer User
     

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151. Know your users
     They might not be who you think they are
     Dev Domain
     

     Expert
     Product
     

     Owner
     Customer User
     He has the last word regarding
     domain implementation
     

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152. Know your users
     They might not be who you think they are
     Dev Domain
     

     Expert
     Product
     

     Owner
     Customer User
     Prioritize development &
     formalize users’ feedback
     

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153. Know your users
     They might not be who you think they are
     Dev Domain
     

     Expert
     Product
     

     Owner
     Customer User
     Power of Life and Death over the
     project
     

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154. Know your users
     They might not be who you think they are
     Dev Domain
     

     Expert
     Product
     

     Owner
     Customer User
     Too often forgotten
     

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155. Know your users
     They might not be who you think they are
     Dev Domain
     

     Expert
     Product
     

     Owner
     Customer User
     Maybe you could spend a day per
     month working with them ?
     

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156. Know your users
     They might not be who you think they are
     Dev Domain
     

     Expert
     Product
     

     Owner
     Customer User
     They design the software
     speci
     fi
     cation
     

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157. Know your users
     They might not be who you think they are
     Dev Domain
     

     Expert
     Product
     

     Owner
     Customer User
     What he understood goes
     

     into production
     

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158. “A loosely coupled software
     architecture and org
     structure to match” is a key
     predictor of:
     — Michael Plöd (@bitboss)
     

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159. “A loosely coupled software
     architecture and org
     structure to match” is a key
     predictor of:
     • Continuous Delivery
     Performance
     — Michael Plöd (@bitboss)
     

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160. “A loosely coupled software
     architecture and org
     structure to match” is a key
     predictor of:
     • Continuous Delivery
     Performance
     • Ability to scale
     organization and increase
     performance linearly
     — Michael Plöd (@bitboss)
     

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161. “A loosely coupled software
     architecture and org
     structure to match” is a key
     predictor of:
     • Continuous Delivery
     Performance
     • Ability to scale
     organization and increase
     performance linearly
     This is what DDD is All About !
     — Michael Plöd (@bitboss)
     

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162. www.lilobase.me @lilobase
     https://roti.express/r/gstywv
     sundayapp.com
     

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