Microservices Architecture: Interview Prep Guide

Microservices Architecture: Interview Prep Guide

Goal: Broad, systematic coverage — from design thinking to production deployment. Built for senior developers moving into architecture roles.

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The Mental Model: Design → Build → Run

graph LR
    A[Foundations] --> B[DDD]
    B --> C[Patterns]
    C --> D[Events]
    D --> E[APIs]
    E --> F[Resilience]
    F --> G[Observability]
    G --> H[Security]
    H --> I[Deployment]
    I --> J[Interview]

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Sections at a Glance

#	Section	Core Topics
01	Architectural Foundations	Styles, CAP, Conway’s Law, Hexagonal, Onion, Clean
02	Domain-Driven Design	Bounded Contexts, Aggregates, Context Mapping, Ubiquitous Language
03	Microservices Patterns	Decomposition, Integration, Service Discovery, Caching, Sidecar, Outbox
04	Event-Driven Architecture	Kafka, CQRS, Event Sourcing, Saga, Messaging Patterns, DLQ
05	API & Communication	REST, gRPC, GraphQL, API Gateway, BFF, Versioning, Configuration
06	Resilience & Reliability	Circuit Breaker, Retry, Bulkhead, Timeout, Rate Limiting, Chaos
07	Observability	Logs, Metrics, Traces, SLO, OpenTelemetry, DORA Metrics
08	Security	OAuth2, JWT, mTLS, Secrets, Zero Trust, Testing Strategies
09	Deployment & Infrastructure	Kubernetes, Helm, GitOps, Blue-Green, Canary, Configuration
10	Interview Prep	Design scenarios, Trade-offs, ADRs, Spring Boot map

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Recommended Reading Order

1. Sections 01–02 — Architecture thinking + DDD (the why behind service boundaries)
2. Sections 03–04 — Patterns + events (the how of building distributed systems)
3. Sections 05–09 — Verify and fill gaps in what you already know
4. Section 10 — Final synthesis through the interview lens

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What Architecture Interviews Actually Test

• Can you decompose a system into coherent services? (DDD)
• Do you understand distributed system trade-offs? (CAP, eventual consistency)
• Can you reason about failure scenarios? (Resilience patterns)
• Do you know how to observe a running system? (Observability)
• Can you articulate why you’d choose one pattern over another?

!!! tip “Breadth first, depth on demand” This guide is intentionally wide. If a concept feels shallow, that’s your signal to go deeper on that specific topic after building the mental map.