Kotlin Library API Design and Compatibility Challenges

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" summary

Covers concrete compatibility failures and concrete fixes: adding a parameter to a public method creates a new signature and breaks binary compatibility; solution is to keep the old method as a synthetic shim annotated @Deprecated(level = HIDDEN) that forwards to the new one. Recommends the JetBrains binary-compatibility-validator Gradle plugin and using API dump diffs, cites Java Language Spec chapter 13 and semantic versioning, shows sealed interfaces/value wrappers to avoid exhaustive enum breaks, and uses RequiresOptIn for experimental APIs.

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" chapters (11)

1. 0:00Introduction
2. 1:29API safety and compatibility
3. 3:36Source vs binary compatibility
4. 5:22Binary Compatibility Validator
5. 6:46Adding function arguments safely
6. 9:25Lambda parameters and interfaces
7. 11:52Enums and sealed classes
8. 13:40Data classes updates
9. 15:06Experimental APIs and versioning
10. 15:49Library development best practices
11. 16:30Conclusion and Q&A

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