API Design · Middle · Question 27 of 75

What is Hyrum's Law?

1APIs double in size every two years
2Every API needs exactly three versions
✓Correct answer: With enough users, every observable behavior of an API will be depended on by somebody, documented or not

Explanation

Field order, timing and undocumented defaults all become de facto contracts. Be careful even with 'internal' changes.

Further reading

Hyrum's Law ↗

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