#3 - A Change in One Service Breaks Others – How to Prevent It | Microservices Interview Question

Описание: In this video, we answer a critical senior-level microservices interview question:

🚨 What happens when a change in one service breaks others?

This isn’t just a technical problem.
It’s a contract problem.

In distributed systems, your API is someone else’s dependency.
Breaking changes can cause production incidents, failed deployments, and system-wide instability.

In this deep dive, we cover:

• Why breaking changes happen
• Backward compatibility principles
• Safe vs breaking API changes
• API versioning strategies
• Contract testing explained
• Schema evolution for event-driven systems
• Expand-and-contract database pattern
• Deprecation strategy best practices
• Who owns backward compatibility?

This is essential knowledge for:
Senior backend engineers
System design interviews
Microservices architects
Engineering leads

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🧠 Key Takeaway:
Stable systems treat compatibility as a feature, not a burden.

If you're preparing for senior system design interviews, this concept is non-negotiable.


00:00 Introduction
00:40 Why Changes Break Systems
02:00 APIs as Contracts
03:15 Backward Compatibility Rules
05:10 Safe vs Breaking Changes
06:30 API Versioning Explained
08:00 Contract Testing
09:30 Schema Evolution for Events
11:00 Expand-and-Contract DB Pattern
12:20 Deprecation Strategy
13:30 Who Owns Compatibility?
14:15 Final Takeaway



microservices
backward compatibility
api versioning
contract testing
system design interview
senior developer interview
schema evolution
expand and contract pattern
distributed systems
event driven architecture
backend architecture
api breaking changes
software engineering best practices


#microservices #systemdesign #backendengineering #softwarearchitecture #interviewprep #apis