Glossary

Stateless Service

A service that keeps no client/session state between requests, so any instance can handle any request.

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Definition

A service that keeps no client/session state between requests, so any instance can handle any request.

How it works

Statelessness is what makes horizontal scaling and load balancing easy — kill or add instances freely, no sticky sessions. Push the state outward: sessions in Redis, data in the DB, files in S3. The standard shape for web/app tiers; only the storage layer is deliberately stateful.

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Common questions

What is Stateless Service?

A service that keeps no client/session state between requests, so any instance can handle any request.

How does Stateless Service work?

Statelessness is what makes horizontal scaling and load balancing easy — kill or add instances freely, no sticky sessions. Push the state outward: sessions in Redis, data in the DB, files in S3. The standard shape for web/app tiers; only the storage layer is deliberately…

What is Stateless Service used for in system design?

Statelessness is what makes horizontal scaling and load balancing easy — kill or add instances freely, no sticky sessions. Push the state outward: sessions in Redis, data in the DB, files in S3. The standard shape for web/app tiers; only the storage layer is deliberately…

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