The 5-Layer Architecture Model

We are using a strict layered model:

App Layer
Module Layer
Core Layer
Shared Layer
Data Layer

Let’s break that down.

App Layer

Navigation and global orchestration only.

Module Layer

Feature-level business logic (archive, tagging, sharing, settings).

Core Layer

Infrastructure:

• Encryption
• Secure storage
• Filesystem
• Config
• Devtools

Shared Layer

Reusable, presentational UI components only.

Data Layer

Encrypted Realm database.

Each layer has boundaries.

No cross-contamination.

If layers bleed into each other, refactoring becomes inevitable.

Folder Structure (Production-Ready From Day One)

We created a structure that supports growth:

src/
  app/
  core/
  modules/
  shared/

This is not over-engineering.

This is prevention.

Most MVPs collapse because everything lives inside screens/.

We are separating:

• Infrastructure from features
• Business logic from UI
• Storage from services
• Reusable systems from product modules

Strict Architectural Rules (Non-Negotiable)

From today onward:

• No business logic inside UI components.
• No direct Realm calls inside screens.
• Repository layer handles database access.
• Services handle business logic.
• Encryption lives only inside core/security.
• File handling lives only inside core/fileSystem.
• Modules never depend directly on other modules.
• No hardcoded theme values in UI.

These rules are boring.

And that’s the point.

Boring architecture scales.