Domain Storytelling (1 day workshop at DDD EU 2019)

Brought to you by Stefan (@hofstef) and Henning (@hschwentner). We
are two DDD Enthusiasts working at WPS – Workplace Solutions GmbH in the beautiful city of Hamburg.

@hofstef @hschwentner

@hofstef @hschwentner Domain Knowledge

@hofstef @hschwentner Fach- sprache Domain Expert IT Expert

@hofstef @hschwentner @hofstef @hschwentner

@hofstef @hschwentner Paul Rayner‘s 3 pillars* of DDD (as explained
at Explore DDD 2018) *) plus Ubiquitous Language as an overarching principle Picture: Martin Schimak @martinschimak

@hofstef @hschwentner Schedule 11:00 Coffee 13:00 Lunch 15:30 Coffee 18:00
DDD (Dinner & Drinks in Downtown?)

@hofstef @hschwentner Schedule 9:45 Big Picture Stories 11:15 Strategic Design
14:00 Domain Model Stories & Implementation Stories 15:45 Integrating Domain Storytelling in the Development Process 17:00 Wrap-Up 17:15 We Model Your Domain!

@hschwentner Do I get a car for this?

@hofstef @hschwentner Leasing Big Picture

@hofstef @hschwentner @hofstef @hschwentner Pictographic Language

@hofstef @hschwentner actor work object activity annotation

@hofstef @hschwentner risk manager contract votes

@hofstef @hschwentner person people system

@hofstef @hschwentner contract passes on signs contract

@hofstef @hschwentner The sales person passes the contract on to
the risk manager. passes on RISK MANAGER SALES PERSON to CONTRACT

@hofstef @hschwentner 1 1 1

@hofstef @hschwentner CUSTOMER 1 SALES- PERSON 2 CAR INSTALLMENT CONTRACT

@hofstef @hschwentner 4 5 CUSTOMER CONTRACT CONTRACT

@hofstef @hschwentner CONCRETE STORIES VS. ABSTRACT PROCESSES

@hofstef @hschwentner 3 good examples are better than 1 bad
abstraction

@hofstef @hschwentner Draw here Leave some empty space there 
Annotations, variations, and purpose Preconditions, assumptions, and triggers

@hofstef @hschwentner Workshops

@hofstef @hschwentner @hofstef @hschwentner

@hofstef @hschwentner Tools

@hofstef @hschwentner Whiteboard Kit Picture: W. Kinkeldei @wkinkeldei

@hofstef @hschwentner PowerPoint, yEd, Viso, gliphy… asks for Reservation (movie,
time, seats) cashier movie-goer 1 Screen plan finds available seats in CineSoft 2 seats recommends 3

@hofstef @hschwentner github.com/WPS/domain-story-modeler

@hofstef @hschwentner Welcome to your (client’s) cinema!

@hofstef @hschwentner Exercise 1 Go To The Movies (Big Picture)

@hofstef @hschwentner Results

@hschwentner Strategic Design

UNDERSTANDING THE WORLD

@hofstef @hschwentner ?

@hofstef @hschwentner Leasing Big Picture with Sub-Domains and Bounded Contexts

@hofstef @hschwentner Bounded Context: Activities that - from an actor’s
perspective - belong together.

@hofstef @hschwentner Activities that belong together:

@hofstef @hschwentner Indicator: only one actor involved xyz context

@hofstef @hschwentner Indicator: one-way information flow abc context xyz context

@hofstef @hschwentner Indicator: different triggers abc context xyz context

@hofstef @hschwentner Indicator: handling the same work object differently

@hofstef @hschwentner More indicators: • Difference in language (see out
Talk at DDD Europe 2018) Some more heuristics: • https://medium.com/nick-tune-tech-strategy-blog • http://verraes.net/#blog

@hofstef @hschwentner Exercise 2

@hofstef @hschwentner Results

@hofstef @hschwentner Leasing - Risk Management

@hofstef @hschwentner Exercises 3+4

@hofstef @hschwentner Result

@hofstef @hschwentner CUSTOMER CONTRACT 3 RISIK MANAGER CONTRACT 7 <<Entity>>
LeasingContract sign() vote()

@hofstef @hschwentner public class LeasingContract { public void sign(SignDate date)
//... public void vote(VoteResult result) //... }

@hofstef @hschwentner CUSTOMER CONTRACT 3 RISK MANAGER CONTRACT 7 <<Entity>>
LeasingContract sign() vote() setVoteResult(…)

@hofstef @hschwentner <<Entity>> LeasingContract sign() vote()

@hofstef @hschwentner <<Entity>> LeasingContract sign() <<Entity>> LeasingContract vote()

@hofstef @hschwentner <<Entity>> LeasingContract sign() vote()

@hofstef @hschwentner <<Entity>> LeasingContract sign() <<Entity>> LeasingContract vote()

package leasingninja.sales; class LeasingContract { /*...*/ } package leasingninja.riskmanagement; class
LeasingContract { /*...*/ }

@hofstef @hschwentner <<Entity>> LeasingVertrag unterzeichne() votiere()

@hofstef @hschwentner <<Entity>> LeasingContract Entities Value Objects Aggregates Services

@hofstef @hschwentner Step 1 Step 2 Step 3

@hofstef @hschwentner Step 2

@hofstef @hschwentner Result

@hofstef @hschwentner From Domain Stories to User Stories

@hofstef @hschwentner “A story is a promise to have a
conversation later between the end-user and developers. Your goal in writing stories is not to work out details, but to discover the most important goals for your project and to organize a project into discrete, testable chunks.” Agile Government Leadership

@hofstef @hschwentner Summary „kite level“ User Goal „sea level“ Sub-Function
„fish level“ 3 Levels of User Stories (Alistair Cockburn)

Structure of a „User Goal“ Story • Who?  Actor
• What?  Activity • Why?  Activity, Annotation, verbal

@hofstef @hschwentner Template <Name> As <Actor> I want to <Goal>
so that I <Purpose>. • Do not follow the template blindly! • Use ubituitous language • Not a specification! • There are other templates

@hofstef @hschwentner Exercises 5

@hofstef @hschwentner Software Developlement as a Series of Conversations

@hofstef @hschwentner • When/how often? • Overview o Use Case
Diagrams • Domain Stories as Documentation o Pictures vs. Storytelling o Use Cases • Domain Storytelling and… o …User Story Mapping o …Behavior-Driven Design (BDD) o …Event Storming

@hofstef @hschwentner A Real-World Example Build Software to Coordinate Road
Work

@hofstef @hschwentner https://www.wps.de/portfolio-items/roads/

@hofstef @hschwentner Guidelines for Moderators

@hofstef @hschwentner • Conflicts • Moderatred vs. Cooperative

Stefan: [email protected] @hofstef speakerdeck.com/hofstef The pictures used in this talk
are public domain, unless noted otherwise. Screenshots and examples © WPS - Workplace Solutions GmbH Henning: [email protected] @hschwentner speakerdeck.com/hschwentner Website: http://domainstorytelling.org Twitter: #DomainStorytelling Slack: https://ddd-cqrs-es.slack.com/ Slack Channel: #domain-storytelling

Domain Storytelling (1 day workshop at DDD EU 2019)

Domain Storytelling (1 day workshop at DDD EU 2019)

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