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Quiz

2948 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 areas2948 Architecture Fundamentals91 Distributed Systems101 Data Architecture90 Cloud Architecture87 Networking96 API & Integration Architecture87 Reliability & Resilience99 Observability92 Performance & Capacity Engineering100 Security Architecture105 Cost Architecture & FinOps102 Business Architecture103 Architecture Communication102 Enterprise Architecture100 Legacy Modernization102 AI-Era Architecture106 Software Architecture & Engineering93 Architecture Patterns94 Architecture Decision-Making101 The Architect's Meta-Skills102 Delivery & Release Engineering103 Platform Engineering & Developer Experience102 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

2948 questions.

  1. Pagination & Filtering intermediate

    Your API issues opaque cursors for keyset pagination. Three weeks after a client stored one, you change the default sort from created_at to relevance_score. The client resumes with the old cursor. What happens, and what should happen?

    2 min answer paginationcursorsversioningsilent failure
  2. Parallel Run advanced

    A financial calculation engine is being replaced and the results must be proven equivalent before cutover. How should a parallel run be designed, and how are discrepancies triaged?

    3 min answer parallel-runmigrationreconciliationfinance
  3. Parallel Run advanced

    A general ledger replacement runs in parallel for five months. The nightly comparison checks daily totals per account class and they match to the penny every single night. Three weeks after cutover, finance finds that about 900 customers have had interest posted to the wrong account class since month two, and the daily totals were always correct. What failed, and which design decision made it possible?

    3 min answer parallel runreconciliationaggregatesgeneral ledger
  4. Parallel Run advanced

    A logistics platform is replacing its core routing system. Should it run the old and new systems in parallel, and for how long?

    2 min answer delhiveryparallel-runverificationcutover
  5. Parallel Run intermediate

    An enterprise runs old and new systems in parallel to validate the replacement. What makes a parallel run effective, and what makes it expensive theatre?

    2 min answer parallel-runverificationcomparisoncutover
  6. Parallel Run advanced

    You are reimplementing a legacy capability. What does running old and new in parallel find that testing cannot?

    2 min answer parallel-runlegacyundocumented-behaviourtriage
  7. 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
  8. Partition Keys & Ordering advanced

    A marketplace in the mould of Flipkart has an order-events topic with 24 partitions keyed by buyer id. One consumer per partition is now the throughput ceiling and the team wants 96 partitions. Per-buyer ordering is a hard requirement and six downstream jobs rebuild their state by replaying the topic. Sequence the change so each step is reversible and say where the point of no return is.

    3 min answer kafkapartitioningorderingmigration
  9. 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
  10. Partition Keys & Ordering intermediate

    A team must choose partition keys for an event stream. What does the choice determine, and what goes wrong when it is chosen carelessly?

    2 min answer partitioningorderinghot-keyparallelism
  11. Partition Keys & Ordering intermediate Multiple choice

    After scaling consumers from 3 to 12, downstream data shows updates applied out of order. What happened?

    2 min answer orderingpartitioningcorrectness
  12. Partition Keys & Ordering advanced

    Alibaba reported a peak of 583,000 order creations per second during Singles' Day 2020. Take that as the sizing input for a log-based order-event pipeline with per-buyer ordering. Roughly how many partitions does the order topic need, and which assumption dominates the error?

    2 min answer alibabapartitionscapacitypeak-event-readiness