multibackend

Multibackend is an architectural approach in which an application or service integrates with multiple backend systems rather than a single backend. It is common in microservices environments, data-driven applications, and scenarios that require interoperability across heterogeneous data stores or legacy systems.

The core idea of multibackend is to provide a unified interface to clients while delegating requests to the appropriate backend. This typically involves an API gateway or backend-for-frontend layer, connectors or adapters for each backend, and an orchestration or workflow layer to coordinate multi-backend operations. Data can be federated, cached, or materialized as needed to meet performance and consistency requirements.

Common design approaches include API gateways with intelligent routing, backend-for-frontend patterns that tailor APIs to client needs, and federated data access through a single query layer such as GraphQL federation. A service mesh may assist with secure communication and observability between backends, while data virtualization and ETL pipelines enable cross-backend data access and integration.

Benefits of multibackend include leveraging specialized backends, enabling gradual modernization, and improving resilience and scalability through component isolation. However, it introduces complexity in terms of latency, cross-backend consistency, distributed transactions, security, governance, and operational monitoring.

Key implementation considerations include clear ownership and SLAs for each backend, consistent authentication and authorization, careful schema and contract management, end-to-end tracing, robust error handling, and comprehensive testing strategies for distributed operations.

Use cases encompass enterprise data integration, combining CRM, ERP, and analytics sources; multi-cloud or hybrid deployments; and progressive modernization where new services replace older systems over time.