Modularizing the Monolith

on YouTube ↗57m

" summary

Monoliths become hard to change because boundaries are missing; the practical fix is to refactor into a vertical slice architecture so each user operation lives front-to-back, then group slices into modules that contain data and a public API. Independence is measurable by counting incoming/outgoing dependencies and spotting hot spots (one case shows 200+ usages between modules, and organizations can explode to thousands of microservices). Static analysis yields a dependency matrix and the DB migration follows a staged approach popularized by Stripe: migrate schema by dual-writing, switch readers, then drop old writes.

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" chapters (13)

1. 0:00Modularizing the monolith
2. 3:55Microservices vs monoliths
3. 7:47Good vs bad monoliths
4. 10:13Layered architectures fail
5. 12:02Vertical slice architecture
6. 15:36Independent modules
7. 17:43Module boundaries in code
8. 20:50Data ownership in modules
9. 25:30Refactoring to vertical slices
10. 34:30Database refactoring
11. 41:59Measuring module independence
12. 45:10Extracting modules
13. 53:20Key takeaways

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