This document provides an introduction to microservices, including a comparison to monolithic architectures. It discusses advantages and disadvantages of both monoliths and microservices. Monoliths have disadvantages including being difficult to change and maintain as well as not scaling well. Microservices aim to address these issues by developing applications as suites of small, independent services. The document outlines some key principles of microservices, such as independent deployment and technology choices, as well as advantages like improved scalability and flexibility.

1. Introduction to
Microservices
Duduman Bogdan Vlad
@vlad_duduman

2. Agenda
 Monoliths
 Monoliths advantages and disadvantages
 Microservices
 Principles of microservices
 Microservices advantages and disadvantages

3. Monoliths
 Netflix. Amazon.com, Ebay, Paypal
 Single-Tiered Software application
 Responsible not for a particular task
 Long build time
 Building and deploying the whole application
 Support only vertical scaling

4. Monoliths - Example

5. Monoliths
 Advantages
 A single layered architecture
 A single technology stack
 A single code base maintained by multiple teams
 Disadvantages
 All parts are interconnected
 Many other systems are connected to your system
 Hard to change, hard to maintain
 Slow innovation
 Hard to move to newer technologies
 Doesn’t scale very well

6. Monoliths
 Disadvantages
 As the team grows, will eventually start to break down
 Technical debt – “Not broken, don’t fix it”

7. Monoliths. Dependencies will kill you

8. The Microservices Way
“An approach to developing a single application as a suite of small
services.” - Martin Fowler

9. Gartner hype cycle

10. Microservices
 First time discussed – 2011
 Just a rebranding of SOA?
 “Micro” indicates the scope is limited to a single functionality

11. Microservices

12. Microservices

13. Microservices. Evolution

14. Microservices. Evolution

15. Microservices - Example

16. Monoliths. Scalability

17. Microservices. Scalability

18. Microservices. Scalability

19. Monoliths. Persistence

20. Microservices. Polyglot persistence

21. Microservices. Advantages
 Simple
 Modularity
 New features as microservices
 Small codebase
 Easy to scale
 Easy to deploy - loosely coupled
 System resilience

22. Microservices. Advantages
 Technology independent
 Replaceable parts
 High performance
 Polyglot persistence
 Easy to test
 Autonomous
 Specification change is frequent

23. Microservices. Advantages
 Single Responsibility Principle
 Light-weight communication

24. Microservices. Principles and practices
 Set up a set of guiding principles
 Create practices that support these principles
 Create example implementations and service templates
 Make it easy for the team to do the right thing
 In order to move to this, you will need to get better at:
 Architecture
 Testing
 Deployment
 A team should be able to rebuild a service in two weeks

25. Microservices. Common Patterns
1. “Almost all the successful microservice stories have started with a monolith
that got too big and was broken up”
2. “Almost all the cases where I’ve heard of a system that was built as a
microservice system from scratch, it has ended up in a serious trouble”

26. Microservices. How? When?

27. Thanks