System Design Interview - Designing from...

Designing from Invariants Software architecture is frequently treated as an exercise in connecting infrastructure components. We often reach for Kafka, Redis, or microservice boundaries as if they are the building blocks of the business logic itself. But when tools come before logic, the resulting design prioritizes infrastructure choices over the problem they are meant to solve. A high reliability system does not start with a distributed queue or a complex workflow engine. It starts with the co