Context is important

• • /mateusz-chrzonstowski
  • /_mat3e_
  • /_mat3e_
  • /mat3e
  •  
  • mat3e.github.io/talks/3pigs/geecon
    github.com/mat3e/3pigs-ddd
  •  
• • 
  • 
  • 

url: sli.do

code: #geecon2022

DDD

Strategic DDD

Bounded Context

Fairy tales

Mother
House
Wolf

How to plan all of this?

EventStorming!

• Golden rule: events (verbs, past tense), NOT data structures (nouns)
• Big Picture ES - to discover domains etc.
• Process-Level ES - to discover Bounded Contexts
• Design-Level ES - for a tactical DDD within a BC
• Commands (change the system's state) & queries (views)

domainlanguage.com/ddd/whirlpool

DDD

Tactical DDD

Tactical DDD - code

What aggregate for The Three Little Pigs?

Concepts

• House building: straw, wood, bricks
• Wolf blowing house down => pig escaping to the neighbor
• Wolf resigning after 2 failures
• Pigs learning from the mistakes and improve
• Skipping:
  • Mother of the pigs
  • Chimney climbing
  • Eating the pigs

So what?

Big Picture

Design-Level

Clean Architecture

User Story/Command

• As a user, I want to get to know a fairy tale, so that I can tell it to others
• As a pig, I want to build a house, so that it fulfills my requirements
  • Documenting & storing the information
• As a pig, I want to visit my neighbor
• As a pig, I want to share my knowledge with my roommates
• As a wolf, I want to blow the pig's house down, so that I can catch the pig
  • Registry - this house is hard to destroy

Thanks!

• Code: github.com/mat3e/3pigs-ddd
• Slides: mat3e.github.io/talks/3pigs/geecon