CRUD Management System

A full-stack CRUD management system built with NestJS and Next.js, designed with a clear separation between authentication data and business data.
The system follows a production-style architecture with authentication, authorization, logging, file uploads, and containerized local development.

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Overview

This project demonstrates how to build a secure, modular CRUD system with:

• Backend APIs built using NestJS
• A Next.js dashboard frontend
• PostgreSQL (Northwind schema) for business data
• MongoDB for users and session management
• AWS S3 for file uploads
• Docker Compose for local reproducibility

The focus is on backend architecture, database design, and real-world application structure.

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Tech Stack

Backend

• NestJS
• PostgreSQL (Northwind schema)
• MongoDB (users & sessions)
• TypeORM
• Authentication & Authorization
• Structured logging (middleware, interceptors)

Frontend

• Next.js (dashboard application)
• React Query (server-state management)
• Axios (API communication)
• Zod (schema-based validation)
• shadcn/ui (UI components)

Infrastructure

• Docker
• Docker Compose
• AWS S3 (file uploads)

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Architecture Overview

• The backend exposes RESTful APIs built with NestJS.
• Authentication and authorization are enforced using guards, middleware, and interceptors.
• Business data is stored in PostgreSQL using a relational schema.
• User identity and session data are stored separately in MongoDB.
• The frontend is a protected Next.js dashboard that consumes secured backend APIs.
• Docker Compose is used to run the entire system locally.

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Data Storage Design

This project uses two databases, each with a clear responsibility.

MongoDB

• Stores application users
• Persists authentication and session data
• Used for identity-related and flexible user data

PostgreSQL

• Stores domain and business data
• Used for CRUD operations based on the Northwind schema
• Enforces relational integrity and structured queries

This separation allows authentication concerns to evolve independently from core business data.

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Authentication & Authorization

• Authentication is handled on the backend using credential-based login
• Authorization rules are enforced using NestJS guards
• Protected API routes require valid authentication context
• Sessions are persisted using MongoDB

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File Uploads

• File uploads are handled by the backend
• Uploaded files are stored in AWS S3
• Metadata is managed through backend services

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Environment Configuration

Both the backend and frontend use local .env files for configuration.

Each project contains its own .env file that must be edited before running the application.

• The backend .env configures databases, authentication, sessions, and external services.
• The frontend .env configures the backend API base URL and client-side settings.

Environment files are created locally and are not committed to version control.

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Running the Project Locally

This project uses Docker Compose to run the required database services. The backend and frontend applications are run locally on different ports.

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Start Database Services

docker-compose up --build

Installing Dependencies

Install all dependencies for all workspaces with a single command:

yarn install

Run the Frontend

cd next
yarn run dev

Run the backend

cd nest
yarn run start:dev