Architecture and Folder Structure for your Next.js SaaS application

MakerKit's primary goals are:

• Solid Foundations - providing you with the necessary code to get up and running with a Saas with minimal configuration
• Extendable and Adaptable - the ability to change and extend the codebase as efficiently as possible

While it's relatively simple to provide a functioning codebase, it's not always easy to make it:

• Simple - a clean codebase quickly understandable by anyone
• Easy to change - a codebase that can be easily changed to a particular domain

Once you start your project, you can begin unpicking and replacing the existing code to adapt it to your application's domain. At the same time, MakerKit may have pushed an update that fixed a bug or added a new cool feature.

The two projects will diverge and inevitably end up in a conflicting state.

Thankfully, Git makes it easy to merge conflicts. But it's still a hassle.

Framework Architecture

To reduce the number of possible conflicts, MakerKit ships with a particular folder structure:

- app
  - (site)
  - (app)
    - dashboard
  - auth
  - invite
- lib
- components

These folders represent four separate layers. MakerKit is an Onion:

Core

Let's talk about the lower level: the core. This layer is a collection of building blocks, utilities, and APIs that make up MakerKit.

This part of the boilerplate is configurable and makes no assumptions about your domain.

You are still welcome to change this code to suit your needs, but you can expect most updates from upstream to change the code in this directory.

Lib and Shared Components

The mid-level is in two separate folders (to avoid excessive nesting):

• lib: here is where we write most domain-related business logic (hooks, contexts, queries, mutations, etc.)
• components: here is where we write components shared across the application

This layer can still be updated by the upstream repository, but you should not expect too many changes unless it's additions for new features or bug fixes.

Routes

Finally, the app layer is the outer layer of the application.

It's entirely dependent on your application, and you should not expect updates from upstream unless for fixing blatantly buggy code.

The kit splits the routes into three separate layouts:

• (site): the routes that are accessible to everyone, even if they are not logged in
• (app): internal routes that are only accessible to authenticated users
• auth: they auth routes, only accessible to unauthenticated users

Websites routes - (site)

If you are building a SaaS, you will probably have a marketing website. This is the place where you can put your landing page, pricing, and other marketing-related pages.

Auth routes - auth

The auth routes are the routes that are accessible to unauthenticated users. This is where your users can sign up, log in, and reset their password.

If a user is already logged in, they will be redirected to the dashboard.

App routes - (app)

The (app) routes are the routes that are only accessible to authenticated users. This is where you can put your dashboard, settings, and other internal pages.

Domain Components

Domain components are co-located together with their routes. This means that you can easily find the components that are used in a particular route.

For example, you find the authentication components at /app/auth/components.

Import Flow

We use eslint to check that imports are flowing correctly through your application: if this feds you up, you can remove them from the eslint configuration at /.eslintrc.json;