Microservice Communication Patterns

# Microservice Communication Patterns

Communication between services is where complexity lives. Choose wisely.

## Synchronous Communication

**REST APIs**

Simple, well-understood, but creates coupling.

**gRPC**

Fast, efficient, strongly typed. Great for internal services.

**GraphQL**

Flexible queries, but adds complexity.

## Asynchronous Communication

**Message Queues**

Decouple services. Reliable delivery. Better for workflows.

**Event Streaming**

Kafka-style. Real-time, scalable, but eventual consistency.

## When to Use What

**Synchronous for:**

- Real-time user requests

- Strong consistency needs

- Simple request-response

**Asynchronous for:**

- Background processing

- Event-driven workflows

- High-volume data

## Service Mesh

Istio, Linkerd for:

- Service discovery

- Load balancing

- Encryption

- Observability

Don't over-engineer. Start simple, evolve as needed.