This chapter discusses Covenant Ko, who works at 11번가 and is the founder and maintainer of the Github organization '용감한친구들'. It also contains Ko's Github profile and tech blog. The chapter then discusses some problems around separation of concerns, propagation of changes, and cycle references. It questions where logic for finding linked or registered accounts should be placed. It introduces the concept of abstract data types and developing object-oriented applications based on this concept. It also mentions model-view separation in application development.

1. Chapter 4
Covenant Ko
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2. - Name. Covenant Ko
- Company. 11번가
- Github 용감한친구들 Organization Founder & Maintainer. https://github.com/brave-people
- Github. https://github.com/KoEonYack
- Tech Blog. https://covenant.tistory.com/ (누적 방문 41만)

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클래스 지향 아님!

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클래스 지향 아님!

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Problem.
We are here!

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Problem.
Solution.

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11. Problem1.
100 100 200
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11 Spring Cloud MSA - 1 https://youtu.be/J-VP0WFEQsY

12. Problem1.
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109p

13. Problem2.
https://medium.com/@jang.wangsu/%EC%84%A4%EA%B3%84-%EC%9A%A9%EC%96%B4-%EC%9D%91%EC%A7%91%EB%8F%84%EC%99%80-%EA%B2%B0%ED%95%A9%EB%8F%84-b5e2b7b210ff
1. (SRP)
2. (Propagation)
3. (Cycle Reference)

14. Problem3.
연동된 계정, 가입한 계정을 찾는 로직을 어디에 주어야할까?

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https://readerr.tistory.com/35
ADT
. (Abstract Data Type, ADT) . (wiki)

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https://readerr.tistory.com/35
ADT
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156p

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https://readerr.tistory.com/35
ADT
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156p

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https://readerr.tistory.com/35
ADT
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156p
ADT의 개념을 기반으로 객체지향 애플리케이션을 개발하는 방식

19. ?
Model.py View.py

20. 113p
Problem Solution
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책임주도설계의 필요성

21. Covenant Ko
Chapter 4