Backend Services

Backend API that powers the DeComplex platform. Provides REST endpoints, authentication, business logic, and integrations used by the Web App, Admin Console, and Mobile App.

Key Features

REST API

Express-based REST endpoints with a clear routing structure and consistent request-response handling.

Authentication & Authorization

JWT-based authentication with role-based access control for companies, admins, and recruiters.

PostgreSQL + Migrations

Sequelize models with migrations and seeders for reproducible environments and stable schema evolution.

Integrations & API Docs

Redis for caching and auxiliary storage, optional RabbitMQ for asynchronous tasks, and Swagger/OpenAPI documentation for API endpoints.

Technology Stack

Node.jsTypeScriptExpressREST APIPostgreSQLSequelizeRedisRabbitMQJWTJoiSwagger / OpenAPIPinoJestSupertest

Architecture Notes

  • Modular API design - Feature-oriented modules with isolated routing layers, validation, and service logic.
  • Data access layer - Sequelize-based persistence with explicit migrations and well-defined query patterns.
  • Security and observability - Helmet, CORS configuration, validation (Joi), and structured logging (Pino) for secure and traceable operations.

Service Architecture

API Server (Express)
Auth Module
Vacancies Module
Applications Module
Company/Admin Management
Email (Nodemailer)
Message Queue (RabbitMQ, optional)
PostgreSQL (Sequelize)
Redis (cache/auxiliary storage)