#Microservice

Last updated    - V4 (16-Sep-2025)

Level	Topic	Subtopics
Basic	Introduction to Microservices	What are Microservices, Monolith vs Microservices, Advantages, Challenges, Use Cases
	Microservices Architecture	Service-Oriented Architecture, Components, Service Boundaries, API Design, Communication Patterns
	RESTful Services	REST Principles, HTTP Methods, URI Design, Status Codes, Statelessness
	Microservice Data Management	Database per Service, Shared Database vs Service Database, Data Consistency, Event Sourcing
	Deployment Basics	Containers, Docker Basics, Service Deployment, Configuration Management, Service Discovery
Intermediate	Inter-Service Communication	Synchronous vs Asynchronous Communication, REST, gRPC, Message Queues, Event-driven Architecture
	API Gateway	API Gateway Patterns, Routing, Authentication, Load Balancing, Throttling
	Service Registry & Discovery	Eureka, Consul, Zookeeper, Client-side vs Server-side Discovery, Health Checks
	Security in Microservices	JWT, OAuth2, OpenID Connect, Secure Service Communication, Role-based Access Control
	Observability & Monitoring	Logging, Metrics, Distributed Tracing, Health Checks, Prometheus/Grafana
Advanced	Resilience & Fault Tolerance	Circuit Breaker, Retry Patterns, Bulkheads, Timeout, Failover Strategies
	Messaging & Event-Driven Architecture	Kafka, RabbitMQ, Event Sourcing, CQRS, Message Patterns
	Microservice Testing	Unit Testing, Integration Testing, Contract Testing, Consumer-driven Contract, End-to-End Testing
	CI/CD & DevOps for Microservices	Pipeline Setup, Blue-Green Deployment, Canary Releases, Rollbacks, Automation
	Performance & Scaling	Horizontal Scaling, Load Balancing, Autoscaling, Bottleneck Analysis, Caching Strategies
Expert	Distributed Systems Concepts	CAP Theorem, Eventual Consistency, Data Partitioning, Consensus Protocols, Distributed Transactions
	Advanced Security & Governance	Zero Trust Architecture, Service Mesh Security, Policy Enforcement, Auditing, Compliance
	Service Mesh	Istio, Linkerd, Envoy, Traffic Routing, Observability, Resilience Patterns
	Cloud-Native Microservices	Kubernetes, Helm Charts, Multi-Cloud Deployment, Stateful vs Stateless Services, Cloud Best Practices
	Emerging Trends & Best Practices	Serverless Microservices, Event-driven Microservices, Micro-Frontends, DevSecOps, Observability 2.0

1. Microservices Basics

1. What are Microservices?
2. Difference between Monolithic and Microservices architectures.
3. Advantages of Microservices.
4. Challenges of Microservices.
5. Use cases for Microservices.
6. What is service decomposition?
7. What is a bounded context?
8. Explain stateless services.
9. Difference between synchronous and asynchronous communication.
10. What is API design in Microservices?
11. What are service boundaries?
12. Explain REST principles in Microservices.
13. What are HTTP methods commonly used in REST APIs?
14. How do you handle error responses in REST APIs?
15. What is idempotency and why is it important?
16. Explain the concept of database per service.
17. Shared database vs service-specific database.
18. How do you ensure data consistency across services?
19. What is eventual consistency?
20. Explain event sourcing in Microservices.
21. What is Docker and why is it used in Microservices?
22. How do you deploy a Microservice using containers?
23. What is service discovery?
24. How do you perform configuration management in Microservices?
25. Explain health checks in Microservices.

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2. Intermediate Microservices

1. Difference between synchronous and asynchronous communication.
2. What is gRPC and when to use it?
3. Explain message queues and event-driven architecture.
4. What is an API Gateway?
5. How does API Gateway handle routing?
6. How does API Gateway provide authentication?
7. What is load balancing in API Gateway?
8. Explain throttling and rate limiting.
9. What is a service registry?
10. Explain Eureka, Consul, and Zookeeper.
11. Difference between client-side and server-side service discovery.
12. How do you implement JWT authentication in Microservices?
13. How do you implement OAuth2 in Microservices?
14. What is OpenID Connect?
15. How do you implement role-based access control (RBAC)?
16. How do you implement logging in distributed Microservices?
17. What is distributed tracing?
18. How do you implement metrics collection?
19. Explain monitoring with Prometheus and Grafana.
20. How do you implement service health checks?
21. Difference between correlation ID and trace ID.
22. What are common challenges in inter-service communication?
23. How do you handle timeouts in service calls?
24. Explain circuit breaker pattern.
25. How do you implement retries in service communication?

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3. Advanced Microservices

1. Explain circuit breaker pattern in detail.
2. What is bulkhead pattern?
3. How do you implement retry strategies?
4. How do you implement failover strategies?
5. Difference between event-driven and request-response communication.
6. How do you implement event sourcing?
7. What is CQRS (Command Query Responsibility Segregation)?
8. How do you implement message-driven Microservices with Kafka?
9. How do you implement message-driven Microservices with RabbitMQ?
10. How do you perform unit testing in Microservices?
11. How do you perform integration testing in Microservices?
12. What is contract testing?
13. Explain consumer-driven contract testing.
14. How do you perform end-to-end testing?
15. Explain CI/CD pipeline for Microservices.
16. What is blue-green deployment?
17. What is canary release deployment?
18. How do you rollback a faulty Microservice release?
19. How do you scale Microservices horizontally?
20. How do you implement load balancing?
21. How do you identify bottlenecks in Microservices?
22. How do you implement caching strategies?
23. What is a distributed cache?
24. How do you optimize performance in Microservices?
25. How do you implement message deduplication in event-driven systems?

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4. Expert Microservices

1. Explain CAP theorem in Microservices.
2. How do you implement distributed transactions?
3. Explain saga pattern for distributed transactions.
4. How do you handle data partitioning?
5. How do you ensure eventual consistency at scale?
6. Explain zero-trust security model.
7. How do you implement service mesh security?
8. What is policy enforcement in Microservices?
9. How do you perform auditing in Microservices?
10. What is Istio and how is it used?
11. Explain Linkerd and Envoy in service mesh.
12. How do you perform traffic routing using a service mesh?
13. How do you implement observability in service mesh?
14. Explain Kubernetes deployment for Microservices.
15. What are Helm charts and why are they used?
16. Difference between stateful and stateless services in Kubernetes.
17. How do you deploy Microservices in multi-cloud environments?
18. Explain serverless Microservices architecture.
19. What are Micro-Frontends?
20. How do you implement DevSecOps for Microservices?
21. Explain emerging trends in Microservices.
22. How do you implement observability 2.0 in Microservices?
23. How do you handle high availability at scale?
24. How do you implement resilient and fault-tolerant Microservices?
25. Best practices for enterprise-level Microservices design and governance.