Building Complexus: How to Architect a Scalable Project Management Frontend with Turborepo

Are you tackling a complex web application? Learn how to architect a robust and scalable frontend for project management systems like Complexus, ensuring maintainability and efficient scaling. This guide dives into the architecture of Complexus, a modern project management system, and the strategic choices made to handle its complexity. Unlock the secrets of building a scalable frontend for project management.

Why a Monorepo? Turborepo as the Foundation for Complexus

For projects like Complexus with multiple applications (project management app, marketing site, documentation) and shared libraries, a monorepo architecture is a game-changer. It offers:

• Simplified dependency management
• Streamlined code sharing
• Atomic commits across related parts
• Enforced consistency

Turborepo manages this setup with a focus on performance, employing intelligent caching and efficient task orchestration to speed up builds, tests, and linting. This can dramatically improve CI/CD pipelines and developer productivity. Using Turbopack with Next.js provides near-instantaneous updates during development.

Complexus Monorepo Structure: A Clear Separation of Concerns

The Complexus monorepo organizes code into apps and packages directories.

complexus-monorepo/
├── apps/
│   ├── projects/ # Core Next.js project management
│   ├── landing/  # Next.js landing page
│   └── docs/     # Documentation site (Nextra)
├── packages/
│   ├── ui/             # Custom UI component library
│   ├── icons/          # Shared SVG icons
│   ├── lib/            # Shared utilities (cn function)
│   ├── tailwind-config/ # Shared Tailwind CSS config
│   ├── eslint-config/   # Shared ESLint config
│   └── tsconfig/       # Shared TypeScript configs
├── package.json        # Root dependencies and scripts
├── pnpm-workspace.yaml # Defines workspace locations
└── turbo.json          # Turborepo pipeline configuration

This structure separates deployable units (apps) from reusable code (packages), promoting modularity and making the codebase easier to navigate and maintain.

Streamlining Development: Reusable Components and Utilities

The packages/ directory promotes code sharing and consistency within the Complexus monorepo. Think of it as a central hub for reusable elements, reducing redundancy and ensuring a unified look and feel across the entire system:

• ui: Custom UI component library, built using Atomic Design principles.
• icons: Manages SVG icons used across all applications.
• lib: Shared utilities. Includes cn, a function combining clsx and tailwind-merge to handle Tailwind class conflicts.
• tailwind-config: Tailwind CSS theme used across all apps and packages.
• eslint-config: ESLint configuration preset for consistent code linting.
• tsconfig: Base tsconfig.json files for other packages to extend.

Domain-Driven Design on the Frontend: Structuring Logic in apps/projects

Within the apps/projects/ directory, Complexus embraces Domain-Driven Design (DDD) by organizing code by feature or domain inside a modules/ directory. This approach keeps related code together.

apps/projects/src/
├ app/ 
├ components/ 
├ lib/          
├ modules/      
│  ├ sprints/  
│  │  ├ components/ 
│  │  ├ hooks/      
│  │  ├ queries/    
│  │  ├ mutations/   
│  │  ├ lib/       
│  │  └ types/     
│  ├ tasks/    
│  │  └..
│  ├ settings/    
│  │  └...
│  └──...        
├── styles/     
└──...

Benefits of Feature-Based Structure for Project Management Systems Development:

• Cohesion: Related code lives together within the project management module.
• Modularity: Features are self-contained.
• Scalability: Easy to add new modules as the project management requirements grow.
• Team Collaboration: Teams can own modules.

React hooks encapsulate logic, state management, and data fetching interactions. Components from the shared ui package build the feature's interface.

Seamless Access Across Subdomains: Shared Authentication with NextAuth.js

Complexus uses subdomains (e.g., workspace-a.complexus.app, workspace-b.complexus.app). NextAuth.js manages user authentication across all subdomains.

To achieve this, configure the session cookie's domain attribute in NextAuth.js.

cookies: {
  sessionToken: {
    name: "__Secure-next-auth.session-token",
    options: {
      httpOnly: true,
      sameSite: "lax",
      path: "/",
      domain: ".example.com", // CRUCIAL: Set domain
      secure: true
    },
  },
}

This allows users to authenticate on any subdomain and seamlessly access all others without needing to log in again.

Documenting Your Project: Nextra for Clear Communication

Complexus uses Nextra for its documentation site (apps/docs). Nextra integrates with Next.js and allows writing documentation in Markdown (MDX), embedding React components directly into the documentation pages.

Conclusion: Architecting for Scalability in Project Management Systems

Building Complexus involved deliberate architectural choices for complexity management, consistency, and scalability. Key elements included:

• Turborepo monorepo
• Shared UI components and utilities
• Domain-Driven Design within the main application
• NextAuth.js configured for cross-subdomain authentication
• Nextra for documentation

These principles are applicable to many large-scale frontend projects. Complexus' architecture prioritizes developer experience through fast builds and clear organization, ensuring a maintainable and scalable end product.