Modularizing Rails Monoliths One Bite at a Time

on YouTube ↗35m

" summary

Claim: a phased modular-monolith refactor using the packwerk gem and lightweight eventing actually reduces coupling and avoids microservice pain. The team moves code into packs with package.yml, runs packwerk check/update/validate to manage violations (initially ~450,000) and clears circular deps, swaps ActiveRecord return types for plain Ruby data objects, and uses rails-event-store for pubsub. A 170-contributor app regains fast tests and clearer ownership, and the approach demonstrably works in production.

AI-written summary · about

" chapters (7)

1. 0:00Introduction
2. 1:30The challenge of scale
3. 4:45Introducing packwerk
4. 9:23Phase 1: Planning and moving
5. 15:32Phase 2: Dependencies
6. 19:54Phase 3: Public interfaces
7. 28:18Maintenance and conclusion

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