Backend

Application Server

Where application business logic runs.

• Data processing
• Authentication and authorization
• Validation
• API endpoints

Common technologies

• Node.js
• Java
• Python
• Go

Database

Types

Relational

• MySQL
• PostgreSQL

NoSQL

• MongoDB
• Redis

API Layer

• Rest APIs
• GraphQL
• gRPC

Authentication & Authorization

• Login Systems
• JWT (Java Web Token)
• OAuth
• RBAC (Role-Based access control)

Caching Layer

• Redis (Cache or NoSQL data store)
• Memcached

Message Queues

• RabbitMQ
• Apache Kafka