The software landscape is changing rapidly, especially in the JavaScript world. There are tons of new tools, a fear of obsolescence, constant ecosystem change, too many choices… 樂 Building long-lasting software is becoming harder and harder as the average lifespan of libraries and frameworks is becoming shorter and shorter. As a business, you don't want to have your engineering department spending all their time doing upkeep. You want them to create value for your customers ❤️ Bastien Duret (https://twitter.com/bast0che) is VP of Engineering at Inato (https://inato.com/). He was confronted with these two problems, and has been experimenting with an approach to software development called Domain-Driven Design (https://en.wikipedia.org/wiki/Domain-driven_design), based on the book by Eric Evans.

1. Javascript fatigue?
Domain-driven design to the rescue
AI-powered
patient recruitment
Bastien Duret
@bast0che

2. Agenda
- Problem: software rot
- Solution: domain-driven design

3. Relevancy of your technical stack

4. The State of Javascript: Front-End
Source: https://stateofjs.com/
2016 2018

5. The State of Javascript: Data Layer
Source: https://stateofjs.com/

6. Familiarity of your team with your codebase

7. Source: https://twitter.com/CarloPescio/status/1070288772586192897
Software entropy
+10% YoY

8. Iterative development

9. Performance of your engineering team

10. The usual solution: THE BIG REWRITE
Source: https://twitter.com/thepracticaldev/status/715623065078644738

11. Don’t try this at home: MICROSERVICES REWRITE

12. Domain-driven design
YOUR
DOMAIN
THE REST
UBIQUITOUS
LANGUAGE
Discussed using

13. Ubiquitous language
Our domain, on the walls Patients recruited over time

14. Getting rid of primitive data types
Value object

15. Layered architecture
YOUR
DOMAIN
THE REST

16. From an anemic domain model...
Fields, but no behavior
Business rule Database query

17. ...to an isolated domain layer
Entity
Repository

18. Separation of concerns: back-end
A use-case

19. Separation of concerns: front-end

20. It is worth it
With Domain-Driven DesignIT projects in the wild

21. Javascript fatigue?
Domain-driven design to the rescue
AI-powered
patient recruitment
Bastien Duret
@bast0che