Pattern 26 / SCALE
Use this when handling more stateless request volume by adding machines.
Horizontal Scaling fits when handling more stateless request volume by adding machines. Mechanism: run multiple identical instances behind routing so any instance can handle any request. Use it for web servers, API workers, background consumers, and stateless compute. The toll: needs load balancing and externalized session/state storage.
Web servers, api workers, background consumers, and stateless compute.
Api tier grows from 4 to 40 containers during peak traffic.
Describe the pressure first, then the mechanism, then the cost. That keeps the design grounded.
Same pressure family