How can functionality be distributed among individual microservices in a microservices architecture?

Distribution of functionality among microservices is usually based on principles of separation of concerns and business domains. Main approaches:

• By business domains: Each microservice is responsible for a specific business process or area (e.g., users, orders, payments).
• By functional capabilities: Division into services implementing specific functions (e.g., authentication, notifications).
• Data isolation: Each microservice owns its database, which helps avoid tight coupling and increases independence.
• Minimization of dependencies: Services interact through well-defined APIs, reducing dependency and simplifying scaling.

Example: in an online store, microservices can be allocated for the product catalog, cart management, order processing, and payment. Each service implements its logic and stores data necessary for its operation.