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Quiz

2868 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 areas2868 Architecture Fundamentals91 Distributed Systems101 Data Architecture90 Cloud Architecture87 Networking86 API & Integration Architecture87 Reliability & Resilience99 Observability92 Performance & Capacity Engineering90 Security Architecture95 Cost Architecture & FinOps92 Business Architecture93 Architecture Communication102 Enterprise Architecture100 Legacy Modernization92 AI-Era Architecture96 Software Architecture & Engineering93 Architecture Patterns94 Architecture Decision-Making101 The Architect's Meta-Skills102 Delivery & Release Engineering103 Platform Engineering & Developer Experience92 Testing & Quality Architecture102 Data Platform Architecture98 Streaming & Real-Time Data103 Data Governance & Semantics91 Frontend & Experience Architecture101 Edge, Mobile & IoT98 Regulatory & Data Protection Architecture99 Assurance, Audit & Model Risk98
Difficulty Any beginner intermediate advanced

2868 questions.

  1. IoT Ingest Architecture advanced

    Design ingestion for millions of devices sending telemetry continuously over unreliable networks.

    1 min answer iotingestprotocolsbackpressure
  2. IoT Ingest Architecture advanced

    Two million devices reconnect simultaneously after a network partition. What happens and what prevents it?

    2 min answer reconnection-stormbackpressurejitteringest
  3. IoT Ingest Architecture advanced

    WeChat's DAGOR overload control (SoCC 2018) sheds load using the time requests spend queued inside a service rather than response time, and drops by business and user priority. How would you apply that to a device-fleet ingest tier, and what must the device do for it to work?

    3 min answer wechatdagoradmission-controlbackpressure
  4. Kappa vs Lambda advanced

    A finance-reporting platform runs a nightly batch job and a streaming job that compute the same daily revenue figure, and the batch number is the one the controller signs. You are asked to retire the batch path. Sequence it so every step is reversible and say where the point of no return is.

    3 min answer lambdareconciliationauditparallel run
  5. Kappa vs Lambda advanced

    A platform maintains separate batch and streaming implementations of the same logic. What does that cost, and what are the alternatives?

    2 min answer lambdakappaduplicationskew
  6. Kappa vs Lambda advanced

    A publisher keeps every piece of published content in one ordered Kafka log and rebuilds every downstream store by replaying it, as The New York Times described in 2017. What does that buy, what does the ordering requirement cost, and where would copying it be a mistake?

    3 min answer new york timeskafkalogreplay
  7. Kappa vs Lambda advanced

    A team replays 60 days of order events through the current job to correct a tax calculation. Side effects are already handled - the replay writes to a shadow table and emits no notifications. The job enriches each order by calling the pricing service for the item's list price. What does the shadow table contain when the replay finishes?

    3 min answer replaydeterminismenrichmenttemporal-join
  8. Kappa vs Lambda advanced

    Walk me through how you would decide whether a new analytics platform needs a batch processing path at all. The team already runs a stream processor, and nobody has asked for historical reprocessing yet.

    3 min answer kappareplayretentionidempotency
  9. Key Management advanced

    A communication platform adds end-to-end encryption to multi-party meetings. What are the hard problems, and which are cryptographic versus operational?

    2 min answer key-managemente2eegroup-keystrust
  10. Key Management advanced

    A crypto exchange must hold customer assets while remaining operationally usable. How should key custody, signing, approval and monitoring be architected?

    2 min answer coindcxcustodyhsmsegregation
  11. Key Management advanced

    A pipeline writes 200 million objects a day and the security review requires per-object encryption with a managed key service. Roughly how many calls to that service does the naive design make, what does it cost, and what changes the answer by two orders of magnitude?

    3 min answer envelope encryptionkmsdata keysthroughput
  12. Key Management advanced

    In a multi-tenant SaaS, would you use one data encryption key for all tenants or one per tenant? Justify.

    2 min answer encryptiontenancyerasure