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Quiz

2667 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 areas2667 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 Architecture86 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 Architecture88 Streaming & Real-Time Data93 Data Governance & Semantics81 Frontend & Experience Architecture91 Edge, Mobile & IoT88 Regulatory & Data Protection Architecture90 Assurance, Audit & Model Risk88
Difficulty Any beginner intermediate advanced

130 questions.

  1. Storage Costs beginner

    A lifecycle rule would move 400 million log objects averaging 6 KB each out of standard object storage into an archive class whose per-GB rate is about 95% lower. Roughly what does the move cost and what does it save per month at 2026 US list prices?

    2 min answer storagelifecyclearchivesmall-objects
  2. Storage Layout & Partitioning beginner Multiple choice

    A new engineer asks why the 8 TB events table in the lakehouse has no index on customer_id when the same column is indexed in the operational Postgres the data came from. What is the actual reason?

    2 min answer partitioningcolumnarpruningparquet
  3. Strangler Fig beginner

    A facade in front of a 12-year-old monolith routes 3 of about 20 capabilities to new services, matched by URL prefix. A new mobile build starts calling an endpoint nobody listed in the facade's configuration. What happens, and what should the facade's behaviour for an unmatched route be?

    3 min answer strangler-applicationfacaderoutingdefault-route
  4. Stream Processing Frameworks beginner

    A team runs 400 events per second through a pipeline with Kafka Streams for routing, Flink for windowed aggregation and a Spark job for a nightly correction pass, maintained by four engineers. Two of the three have had production incidents this quarter. What would you remove, what would you keep, and what would you leave alone even though it looks odd?

    3 min answer simplificationoperational costframework choiceright-sizing
  5. Stream-Table Duality beginner

    A service keeps an in-memory map of product prices built by consuming a compacted topic, instead of calling the pricing service on each request. A colleague asks why the map is not just a cache. What is the honest answer, and what does the service now own?

    2 min answer materialized viewcompactioncacheconsistency
  6. Stream-Table Duality beginner

    A team is told that a table and a stream are two views of the same thing. They have a Postgres table holding 12 million account balances and are asked to produce the stream of changes that produced it. Why does the equivalence only run one way in practice, and what has to exist before it runs the other way?

    3 min answer changelogcompactioncdcoutbox
  7. Streaming vs Batch beginner Multiple choice

    An hourly batch job writes each hour's aggregate into a dt/hour partition and is safe to rerun after any crash. The team reimplements the same logic as a streaming job writing to the same table. The streaming job is at-least-once and now produces duplicate rows after every restart. What made the batch version's retries safe?

    2 min answer streamingbatchidempotencysinks
  8. Sync vs Async beginner

    A team moves a slow 800 ms enrichment call out of the request path onto a queue. Request p99 drops immediately, total system throughput does not improve, and the time until the user sees the enriched result gets worse. Why does the queue not reduce the work?

    3 min answer asyncqueuesthroughputlittles-law
  9. TCP/IP beginner Multiple choice

    A 180 KB JSON response takes about 400 ms to reach a client 90 ms away on a connection whose handshake has just finished. The handler took 12 ms and the link has 200 Mbps spare. Measuring from the moment the request is written, what sets the floor?

    2 min answer tcpslow-startcongestion-windowround-trips
  10. Team Topologies beginner Multiple choice

    A team of four engineers owns one service with a 24/7 paging rota. Leadership wants them to take on two more services of similar size. Which fact about the rota decides whether that is possible?

    3 min answer team-topologieson-callcognitive-loadownership
  11. Technology Architecture beginner

    An internal team and a packaged-software vendor both pick the same message serialisation format this quarter. Two years later the internal team replaces it in a single sprint. The vendor still supports it and expects to for another decade - an ERP vendor in SAP's position has customers whose 12-year-old integrations must keep working across a major release. Nothing about the technology differs. What makes the same choice a different decision for each of them?

    3 min answer technology-architecturereversibilitybackward-compatibilitydependents
  12. Test Pyramid Shapes beginner Multiple choice

    A team has 3200 unit tests that run in 90 seconds, 40 integration tests and 12 end-to-end tests. Over six months it shipped 19 defects to production and 14 of them were wiring faults - a wrong column name in a query, a header the downstream service rejected, a queue bound to the wrong exchange. Which change to the suite's shape actually addresses that?

    3 min answer test-pyramiddefect-escapeintegration-testswiring-defects