Module 4
Modular Monolith
One deployable unit with real, enforced internal boundaries: what makes a monolith modular rather than merely large, how modules own their data, and how to keep extraction cheap without paying for distribution.
What you will be able to do
- Distinguish a modular monolith from both a big ball of mud and a set of microservices.
- Define a module contract and enforce it mechanically rather than by convention.
- Give a module ownership of its data inside a single database.
- Use in-process events to decouple modules without introducing a network.
- Prepare a module for extraction and judge when extraction is actually warranted.
- 11 min
01What Makes a Monolith Modular
One deployable, several modules, and boundaries that something in the build actually refuses to let you cross. Without the third part it is just a large application.
- 11 min
02Data Ownership Inside One Database
The hard half of modularity. One database can still give each module exclusive ownership of its tables — and doing so is what decides whether extraction is ever possible.
- 9 min
03Keeping Extraction Cheap Without Paying For It Now
A modular monolith should make extracting a module a decision you can take later at moderate cost — without adopting distributed-system costs today for a service you may never need.
Modular Monolith
6 questions · pass at 75%