Microservices concepts: middleware and observability

Problem Discuss core microservices concepts — the role of middleware and how observability is achieved in a microservices architecture.

Be ready to discuss

• Middleware: cross-cutting request handling (auth, logging, rate limiting), API gateways, and service-to-service communication.
• Observability pillars: logging, metrics, and distributed tracing (correlation/trace IDs across services).
• Health checks, monitoring, and alerting.
• How observability helps debug latency and failures across service boundaries.