This document outlines Pedro Gomez's presentation on clean architecture and software design principles at the Karumi Dojo. It introduces clean architecture concepts like separation of concerns using layers and independence from frameworks. It then discusses how Karumi applies these principles using patterns like Model-View-Presenter and dependency injection. The document concludes by introducing a sample Kata Contacts app to practice these techniques.

1. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Karumi Dojo: Kata Contacts
Pedro Vicente Gómez Sánchez
Senior Mobile Developer at Karumi
pedro@karumi.com
@pedro_g_s
github.com/pedrovgs

2. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs

3. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Sergio Gutierrez
Senior Mobile Developer
Alberto Gragera
Technical Director
Jorge Barroso
Google Developer Expert
Davide Mendolia
Senior Full Stack Engineer

4. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs

5. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Karumi Dojo
● We are here to practice and learn.
● This exercise is meant to be collaborative, not
competitive.
● Try to open your mind to new concepts.

6. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Karumi Dojo
● We are here to practice architecture.
● Keep always in mind the S.O.L.I.D principles.
● We are going to practice pair programming.

7. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Clean Architecture

8. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs

9. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Clean Architecture Principles
● Separation of concerns using layers.
● Independent of Framework or third party libraries.
● Testable.
● Independent of UI or Database.
● The Dependency Rule.

10. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Clean Architecture Principles
● Entities representing enterprise business rules.
● Use cases of the software.
● Adapters to be decoupled from boundaries.
● Platform/Framework as a delivery mechanism.
● Data mapping.

11. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Clean Architecture Conclusion
“Conforming to these simple rules is not hard, and will
save you a lot of headaches going forward. By separating
the software into layers, and conforming to The
Dependency Rule, you will create a system that is
intrinsically testable, with all the benefits that implies.
When any of the external parts of the system become
obsolete, like the database, or the web framework, you can
replace those obsolete elements with a minimum of fuss.” -
Robert C. Martin

12. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Clean Architecture
Karumi Style

13. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Clean Architecture Karumi Style
● Model View Presenter and Presentation Models.
● Use cases
● Repositories to abstract the data origin.
● Adapters to abstract third party libraries.
● Data mapping.

14. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Time to practice!!!

15. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Rules:
● Do not start coding until you understand the requirements.
● Do not start coding without thinking in the most important
part of the domain.
● Today your notebook is more important than your laptop.
● Think carefully the patterns and responsibilities
associated to every class.

16. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Tips
● Baby steps.
● Think before to code.
● Write always testable code.

17. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Kata Contacts
● Command line application to handle your agenda.
● All the data is local but in the future will consume an
external API.
● The user can add a contact.
● The user can list all the contacts already added.

18. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Are you ready?

19. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Business Requirements

20. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Entities

21. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Data Storage

22. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Use Cases

23. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
User Interface

24. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Changing Requirements

25. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Testing

26. Pedro V. Gómez Sánchez - pedro@karumi.com - @pedro_g_s - github.com/pedrovgs
Resources
● The Clean Architecture - Robert C. Martin
● Kata Contacts - Karumi
● Rosie - Karumi