면접 준비 내용

면접 준비 내용을 정리합니다.

정리 해야하는 내역

1. Web & Network

1.1 HTTP & API

• HTTP 1.1 / HTTP 2 / HTTP 3
• HTTPS / TLS Handshake
• REST / GraphQL / gRPC
• Status Code / Header / Cookie
• Content Negotiation
• Idempotent / Safe Method
• API Versioning
• Pagination / Filtering / Sorting
• Rate Limit 정책 설계

2. OS & Runtime

2.1 Linux

• Process lifecycle
• Context switching
• Virtual memory
• Page cache
• File descriptor limit
• epoll / kqueue

2.2 Runtime

• Thread vs Event Loop
• Node.js event loop phases
• Async I/O
• Promise / Callback / Stream
• Backpressure
• GC 알고리즘
• Heap snapshot
• Flamegraph
• Memory leak 패턴

3. Data & Storage (Core)

3.1 RDB (OLTP)

• Schema design
• Normalization / Denormalization
• Index design (B-Tree, covering index)
• ACID
• Isolation Level
• Lock (row / gap / next-key)
• Deadlock handling
• Execution plan 분석
• Partitioning
• Sharding
• Replication (sync / async)
• Read replica lag 대응
• Zero-downtime migration

3.2 Cache & KV Store

• Redis 자료구조
• TTL 전략
• Cache Aside / Write Through / Write Behind
• Cache invalidation
• Hot key 대응
• Session store
• Distributed lock (Redlock, fencing token)
• Cache stampede 방지

3.3 Data Modeling

• ERD
• Domain model
• Aggregate boundary
• Data consistency rule
• Schema versioning
• Backward compatibility

4. Messaging & Data Pipeline

• Event-driven architecture
• Message Queue: SQS
• Message Queue: Kafka
• Message Queue: RabbitMQ
• Message Queue: BullMQ
• Delivery semantics
• At-least-once
• At-most-once
• Exactly-once (실무 한계)
• Idempotency key
• Deduplication 전략
• Ordering guarantee
• Consumer group
• DLQ
• Retry / Backoff
• Replay / Backfill
• CDC (Debezium 등)
• Outbox Pattern
• Saga Pattern (Choreography / Orchestration)
• Backpressure 제어
• Shadow traffic

5. Performance & Scalability

• Query optimization
• Index tuning
• Connection pool sizing
• Thread pool sizing
• Cache strategy
• Lock contention 분석
• CPU / Memory profiling
• Bottleneck tracing
• Load test (k6)
• Autoscaling
• Horizontal vs Vertical scaling
• Capacity planning
• Queue depth 기반 scaling
• Hot partition 대응

6. Observability

6.1 Logging

• Structured logging
• Correlation ID / Trace ID
• Log pipeline (Promtail -> Loki -> S3)
• Log sampling
• PII masking

6.2 Metrics

• RED / USE method
• Prometheus
• Cardinality 관리
• Thanos
• Long-term retention

6.3 Tracing

• OpenTelemetry
• Trace context propagation

6.4 Reliability

• SLI / SLO / Error budget
• Alert fatigue 방지
• Incident runbook

7. Infrastructure & Cloud

7.1 네트워크 인프라

• Reverse Proxy (Nginx, Envoy)
• Load Balancer (L4/L7)
• CDN (Cache Key, TTL, Invalidation)
• DNS 구조 & TTL
• NAT / Public vs Private subnet

7.2 AWS

• EC2 / ASG / ALB
• VPC / Subnet / NAT / SG
• RDS / Aurora
• ElastiCache
• S3
• IAM
• SQS / SNS / EventBridge
• CloudWatch
• EBS vs Instance store

7.3 Container

• Docker
• Docker Compose
• Multi-stage build
• Image size optimization

7.4 Kubernetes

• Pod / Deployment / Service / Ingress
• HPA / VPA
• ConfigMap / Secret
• Resource request / limit
• Liveness / Readiness probe
• PodDisruptionBudget
• Node autoscaling

8. CI/CD & Delivery

• Git Flow / Trunk based
• GitHub Actions
• Build cache
• Docker image build pipeline
• Helm
• ArgoCD (GitOps)
• Blue/Green
• Canary
• Feature flag 시스템
• Rollback 전략
• Zero-downtime deployment
• DB migration 전략

9. Testing & Quality

• Unit test
• Integration test
• E2E test (supertest)
• Contract test
• Test fixture 전략
• Test isolation
• Deterministic test
• Load test automation
• Chaos testing (optional)

10. Security

10.1 인증 & 보안

• Session / JWT
• OAuth2 / OIDC
• Refresh Token Rotation
• Token Revocation
• CSRF Protection
• CORS / CSP

10.2 웹/앱 보안

• SQL Injection
• XSS / CSRF
• SSRF
• JWT security
• Secret management (KMS / Vault)
• TLS config
• Rate limit
• WAF
• Audit log
• Least privilege IAM
• Dependency vulnerability scanning

11. Reliability Engineering

• Timeout
• Retry / Backoff
• Circuit breaker
• Bulkhead
• Graceful shutdown
• Idempotent consumer
• Data recovery
• Backup / Restore
• DR strategy (multi-region)
• RCA / Postmortem 문화

12. Architecture & Design

• Layered / Clean / Hexagonal
• DDD
• Monolith vs Microservice
• Event-driven
• API versioning
• Backward compatibility
• Schema evolution
• Tech debt management
• ADR (Architecture Decision Record)

13. Cost & Operations (FinOps)

• AWS pricing 구조
• Reserved Instance / Savings Plan
• Storage tiering
• Egress cost 관리
• Autoscaling 비용 최적화
• Cost anomaly detection
• Budget alert
• Resource right-sizing

14. Senior Engineer Capabilities

• 기술 의사결정
• 트레이드오프 설명
• 시스템 설계 인터뷰 대응
• 장애 대응 리딩 (Incident Commander)
• 데이터 기반 의사결정
• 멘토링
• 기술 로드맵 수립
• RFC 작성
• Cross-team communication
• 채용 인터뷰