Suggest an editImprove this articleRefine the answer for “Why is REST not always the best choice for microservices?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)**REST** is not always optimal for microservices because it was designed for client-server applications, not for internal communication among many services: at scale it limits flexibility and performance. **Key point:** REST works well for external APIs, but for internal microservices, where speed, asynchrony, and loose coupling matter, better alternatives are gRPC or async messaging.Shown above the full answer for quick recall.Answer (EN)ImageREST is not always optimal for microservices because it was designed for **client-server applications**, not for **internal communication among many services**. At scale, it starts to limit flexibility and performance. ### 1. **High overhead** Every REST request is a separate HTTP connection with JSON serialization and headers. For internal calls between services, this creates unnecessary load and latency. ### 2. **Complexity in long call chains** REST requires sequential requests: one service waits for another's response. In a distributed system this slows down the data flow and increases the risk of failures. ### 3. **No native support for event-driven behavior** REST is a synchronous protocol. If you need to notify other services about events ("order created", "payment completed"), the REST approach is inefficient: it is better to use a *message broker* (Kafka, RabbitMQ). ### 4. **Problems with API versioning and evolution** Microservices often evolve independently, while REST contracts rigidly fix the data structure. Any change requires maintaining several API versions. ### 5. **Better alternatives for internal communication** - **gRPC**: a binary protocol, faster and more compact than JSON. - **Async messaging (Kafka, NATS, RabbitMQ)**: for event-driven systems. - **GraphQL or internal gateways**: for aggregation and flexible queries. **Summary:** > REST works well for external APIs, but is not always efficient for internal microservices, > where speed, asynchrony, and loose coupling matter more.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.