Modular Monolith Pattern
ELI5 — The Vibe Check
A modular monolith is a single deployable app that's internally organized into independent modules with clear boundaries. It's the 'best of both worlds' — the simplicity of a monolith with the structure of microservices. Many teams should try this BEFORE going to microservices.
Real Talk
An architectural pattern where a monolithic application is internally structured into well-defined, loosely-coupled modules with explicit boundaries, encapsulated data, and clear interfaces. Modules communicate through well-defined APIs or an internal event bus, making it straightforward to extract into microservices later if needed.
When You'll Hear This
"Start with a modular monolith. If a module needs to scale independently, extract it into a service." / "A modular monolith gives you 80% of microservices benefits with 20% of the complexity."
Related Terms
Bounded Context
A bounded context is a boundary where a particular model and language applies. 'Customer' means one thing in Sales and something different in Shipping.
Distributed Monolith
A distributed monolith is what happens when you split your monolith into microservices but they're all still tightly coupled.
Microservice
Microservices is an architecture where instead of one big app, you have many tiny apps that each do one thing.
Monolith
A monolith is one big application that does everything. User management, payments, emails, notifications — all in the same codebase, deployed together.