The document discusses the current state of software architecture in the Java community, criticizing the neglect of good design practices and questioning the efficacy of microservices. It emphasizes the importance of structured monoliths, highlights various architectural patterns and strategies, and argues for a collaborative approach to software architecture that fosters agility. Prominent figures in the field are quoted to underline key concepts such as the necessity of architecture in software development.

1. Rethink your
Architecture
Marten Deinum

4. „I think there has been a general abandonment
of good design and development practices in
the Java community.”
–Vaughn Vernon

6. „If you can't build a structured monolith, what
makes you think microservices are the answer?”
–Simon Brown

7. Architectural Crisis
CQRS
MVC
DDD
(S)EDA
μServices SOA
CBD
Anemic Domain Model
Layers/Tiers/Slices
DCI
Pipes and Filters
Transaction Script

9. Software Architecture
Software architecture isn’t about big design up front
Every software team needs to consider software
architecture
The software architecture role is about coding,
coaching and collaboration
You don’t need to use UML
A good software architecture enables agility
–Simon Brown (Software Architecture for Developers)

10. Software Architecture
„Architecture is like weather: you can’t have
none”
– Oliver Gierke

11. Software Architecture
Domain
Presentation
Service
Data Access
Presentation
Service
Data Access
DTO
Domain

12. Software Architecture
Presentation
Service
Data Access
Presentation
Service
Data Access

13. Software Architecture
Presentation
Service
Data Access
Presentation
Service
Data Access

14. Software Architecture
Presentation
Service
Data Access
Presentation
Service
Data Access
Presentation
Service
Data Access

15. Software Architecture
Presentation
Service
Data Access
Presentation
Service
Data Access
Presentation
Service
Data Access

16. Big Ball of Mud

17. Layers
biz.deinum.app.web
biz.deinum.app.service
biz.deinum.app.repository
biz.deinum.app.domain
biz.deinum.app.dto
Presentation
Service
Data Access
DTO
Domain

18. Layers
biz.deinum.app.service.module
biz.deinum.app.module.service
Presentation
Service
Data Access
DTO
Domain

19. Layers
public interface UserService { … }
public class UserServiceImpl
implements UserService { … }

20. Layers
public interface UserRepository { … }
public class JpaUserRepository
implements UserRepository { … }

21. “OOP to me means only messaging, local
retention and protection and hiding of state-process,
and extreme LateBinding of all things”
– Alan Kay (2003)

22. Layers
Presentation
Service
Data Access
DTO
Domain
public interface UserService {…}
public class UserServiceImpl
implements UserService {…}
public interface UserRepository {…}
public class JpaUserRepository
implements UserRepository {…}
public class User {
public User() {…}
}

23. „We don’t build layered software, we have a
couple of domains that interact.”
– Russ Miles (2013)

24. Life Preserver Pattern
Integration
Core

25. Life Preserver Pattern
Integration
Core
User
Event
web
security
ws

26. Slices
biz.deinum.app.user
biz.deinum.app.user.web
biz.deinum.app.order
biz.deinum.app.order.web
biz.deinum.app.order.ws
Presentation
Service
Data Access
DTO
Domain

27. Software Architecture
Integration
Core
User
Event
web
security
ws

30. Reading List