Software → System Design
Stateless
Describes a component or protocol that does not retain client-specific state between requests.
Motivation
Stateless design solves the problem of scaling and replacing service instances more easily.
Where it fits
Statelessness is common in web services, APIs, load-balanced systems, and cloud deployments.
Mental model
Each request contains enough information for the service to handle it without relying on local memory from previous requests.
Common mistakes
- Assuming stateless means no data exists anywhere.
- Hiding state in caches, sessions, or sticky load balancing.
- Ignoring authentication and request context.
Subconcepts
- Stateless Service (Stateless Service) — A service that does not require local per-client state to handle subsequent requests.