Building a Modular Monolith with Next.js

Microservices are not the default answer. For most teams, a well-structured modular monolith ships faster and is far easier to operate.

In this post we walk through how we structure a Next.js application into feature modules, a service layer and a repository layer — keeping business logic out of components and route handlers thin.

Layers

Route handlers validate and delegate. Services own business rules. Repositories own Prisma queries. This separation keeps each piece testable and swappable.