Portfolio ↗

Quiz

2707 questions of the kind that actually get asked — in interviews, in architecture review boards, and by the person who has to run the thing at 3 AM. Every answer states the trade-off rather than the slogan, and says when the obvious choice is the wrong one.

All areas2707 Architecture Fundamentals81 Distributed Systems101 Data Architecture90 Cloud Architecture87 Networking86 API & Integration Architecture78 Reliability & Resilience88 Observability81 Performance & Capacity Engineering90 Security Architecture95 Cost Architecture & FinOps92 Business Architecture93 Architecture Communication91 Enterprise Architecture91 Legacy Modernization92 AI-Era Architecture96 Software Architecture & Engineering84 Architecture Patterns84 Architecture Decision-Making91 The Architect's Meta-Skills92 Delivery & Release Engineering93 Platform Engineering & Developer Experience92 Testing & Quality Architecture90 Data Platform Architecture98 Streaming & Real-Time Data93 Data Governance & Semantics91 Frontend & Experience Architecture91 Edge, Mobile & IoT88 Regulatory & Data Protection Architecture90 Assurance, Audit & Model Risk98
Difficulty Any beginner intermediate advanced

2707 questions.

  1. Backward Compatibility beginner

    Your API returns a JSON object. Which of these changes can break a client you have never met: adding a field, removing a field, changing a field's type, adding a value to an enum, reordering keys, or making an optional field always present?

    3 min answer backward compatibilityjsonenumsparsers
  2. Batch Orchestration advanced

    A data platform's batch jobs have complex interdependencies and a failure early in the night cascades. What orchestration properties matter?

    2 min answer orchestrationdependenciesidempotencybackfill
  3. Batch Orchestration advanced

    On the last Sunday in October a UK data platform's 01:30 daily job ran twice and duplicated rows in a revenue table. On the last Sunday in March the same job did not run at all. The scheduler is configured in local time. What failed, and what is the structural fix?

    3 min answer schedulingdaylight savingidempotencyutc
  4. Batch Orchestration advanced

    The batch orchestrator's scheduler process dies at 02:40 with about 30 tasks already running on workers. It is restarted at 03:00. The nightly load includes a MERGE into a revenue table and a push to a payments vendor. What happens between 02:40 and 03:15?

    2 min answer orchestrationidempotencyat-least-oncezombie-tasks
  5. BFF for Experience advanced

    A team adds a backend-for-frontend per client - web, iOS, Android, partner. Latency and payload sizes improve immediately. What has been given up, and when does that bill arrive?

    3 min answer bffcouplingownershipduplication
  6. BFF for Experience advanced

    A travel platform serves web, iOS, Android and partner integrations from the same services. When is a backend-for-frontend justified?

    1 min answer bffapi-designaggregationcoupling
  7. BFF for Experience intermediate Multiple choice

    Six product teams ship a web app and an iOS app against 23 domain services. A typical screen needs data from four to nine of them. Mobile releases take roughly three weeks to reach 90% of installs. Round-trip time on mobile networks is 60-150 ms. The platform team must pick one aggregation approach for the next two years. Which fits?

    2 min answer bffownershipapi-shapesversion-tail
  8. BFF for Experience intermediate

    Your mobile BFF now contains pricing logic, entitlement checks and order validation. What has gone wrong?

    2 min answer bffboundariesdrift
  9. Backend for Frontend intermediate

    A platform has a backend-for-frontend per client, and they have diverged with duplicated logic. Is BFF still the right pattern?

    2 min answer bffduplicationownershipshared-logic
  10. Backend for Frontend intermediate

    A product runs on web, iOS, Android and a television app. The shared API team is the bottleneck for every client change. Design the fix.

    3 min answer bffapi-designnetflixownership
  11. Backend for Frontend intermediate

    A quick-commerce platform serves a mobile app, a web app and a partner API from the same services. When does a backend-for-frontend earn its place?

    2 min answer zeptobffaggregationclients
  12. Backend for Frontend intermediate

    A travel platform with Booking.com's catalogue breadth replaces nine client-side calls with one backend-for-frontend call that fans out to the same nine services. Mobile p99 improves by 40% on the first day. Each of the nine services holds 99.9% availability. What has the team given up, and when does the bill arrive?

    3 min answer bffaggregationavailabilitypartial rendering