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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

65 questions in Streaming & Real-Time Data.

  1. Exactly-Once Semantics advanced

    A vendor claims their streaming platform provides exactly-once processing. How do you evaluate the claim?

    1 min answer streamingsemanticsvendorcorrectness
  2. Exactly-Once Semantics advanced

    Your streaming job has exactly-once semantics enabled. Customers report receiving the same email twice. Explain.

    2 min answer streamingdelivery-guaranteesidempotency
  3. Feature Freshness advanced

    ByteDance's Monolith paper (ORSUM at RecSys 2022) describes a collisionless embedding table for a recommender trained on the interaction stream, where new user and item ids arrive continuously so the key space has no ceiling. What bounds the memory, and what does each bound cost in model quality?

    3 min answer bytedancemonolithembeddingsonline training
  4. Feature Freshness advanced

    ByteDance's Monolith paper (RecSys workshop 2022) describes training recommendation models on user feedback as it arrives rather than in nightly batches, and states that system reliability was deliberately traded for real-time learning. What does that trade actually look like in the pipeline, and when is a nightly batch the better engineering decision?

    2 min answer bytedanceonline trainingembeddingsfreshness
  5. Feature Freshness advanced

    Delivery ETAs are computed by a model using live traffic and restaurant load. The model's features are computed in batch overnight. What is wrong?

    2 min answer doordashmlfeaturesskew
  6. Feature Freshness advanced

    How should feature freshness requirements be decided, and what does getting them wrong cost?

    2 min answer feature-freshnesslatencycostskew
  7. 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
  8. 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
  9. 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
  10. 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
  11. Partition Keys & Ordering advanced

    A location pipeline must choose a partition key. What are the candidates, and what does each optimise for?

    2 min answer olapartitioningorderingskew
  12. Partition Keys & Ordering advanced

    A stream requires ordering per user but not globally. How should partitioning be designed, and what breaks it?

    2 min answer partitioningorderinghot-keysrebalancing