Senior Cross-Cutting
System design, the infrastructure stack (Docker → K8s → Terraform → cloud → observability), security, testing, version control, and code quality.
- chapters
- 13
- objectives
- 31
- core
- 19
- est. time
- 4h 33m
- 01 6.1 System design fundamentals ★ core
The 4-step interview framework, back-of-the-envelope estimation, the building blocks, and designing for scalability/availability/reliability while naming bottlenecks.
- 02 6.2.1 Containers (Docker) ★ core
Image vs container, layers and layer caching (why Dockerfile order matters), writing a Dockerfile, multi-stage builds, and docker-compose.
- 03 6.2.2 Orchestration (Kubernetes) ★ core
The core K8s objects (Pod, Deployment, Service, Ingress, ConfigMap, Secret) and a hands-on deploy on local K8s.
- 04 6.2.3 CI/CD
Pipeline stages (build → test → deploy) and writing a basic GitHub Actions workflow.
- 05 6.2.4 Infrastructure as Code (Terraform) ★ core
Providers, resources, and state (and why state/remote state matters), modules for reuse, and plan vs apply.
- 06 6.2.5 Cloud fundamentals
Compute/storage/networking primitives, regions & availability zones, and IAM/least privilege.
- 07 6.2.6 Networking
Load balancers, reverse proxies, DNS, TLS/HTTPS, CDNs, VPCs/subnets, and firewalls/security groups.
- 08 6.2.7 Observability ★ core
The three pillars — logs, metrics, traces — what question each answers, and the tool concepts (Prometheus, Grafana, OpenTelemetry).
- 09 6.2.8 Deployment strategies
Blue-green, canary, and rolling deploys — define each and give the tradeoff.
- 10 6.3 Security fundamentals ★ core
OWASP Top 10:2025 awareness, the injection/XSS/CSRF trio and how they differ, hashing vs encryption, password salting, and least privilege.
- 11 6.4 Testing ★ core
The test pyramid and why; unit vs integration vs e2e; mocking/stubbing; TDD; and why 100% coverage isn't the goal.
- 12 6.5 Version control intricacies ★ core
Branching strategies (trunk-based vs GitHub Flow vs Git Flow), rebase vs merge (and when NOT to rebase shared branches), cherry-pick, and conflicts.
- 13 6.6 Code quality
Code-review practices (small PRs, design not just bugs) and clean-code/refactoring principles.
Section assessment
Harder, multi-concept questions drawn from across the module. Aim for 75%.
- 01hard
Consistent hashing is primarily used to:
- 02hard
A Kubernetes Secret encrypts its data by default.
- 03hard
Hashing vs encryption:
- 04medium
The FIRST step of the system-design interview framework is:
- 05medium
Why put `COPY package.json` + install BEFORE `COPY . .` in a Dockerfile?
- 06medium
Multi-stage builds primarily give you:
- 07medium
Which K8s object gives a stable network endpoint for a set of pods?
- 08medium
Terraform state matters because it:
- 09medium
Which pillar answers “what was the exact path of this one slow request across services?”
- 10medium
Which strategy lets you instantly roll the entire fleet back by flipping a switch?
- 11medium
The correct primary defense against SQL injection is:
- 12medium
Passwords should be stored using: