Portfolio ↗

Quiz

2627 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 areas2627 Architecture Fundamentals81 Distributed Systems101 Data Architecture90 Cloud Architecture77 Networking86 API & Integration Architecture78 Reliability & Resilience88 Observability81 Performance & Capacity Engineering90 Security Architecture85 Cost Architecture & FinOps82 Business Architecture93 Architecture Communication91 Enterprise Architecture91 Legacy Modernization82 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

117 questions.

  1. Client Feature Flags beginner

    You turn off a feature flag evaluated in the browser. Some users keep seeing the old behaviour for hours. Why, and what should the design do about it?

    2 min answer feature-flagscachingpropagationclient-architecture
  2. Cloud Pricing Models beginner

    From 1 February 2024 a major cloud provider began billing every public IPv4 address at roughly $0.005 per address-hour. Your estate runs about 2000 instances plus managed databases, load balancers and per-branch preview environments. Roughly what did that add per year, and what should change because of it?

    3 min answer cloud pricingipv4estimationorphaned resources
  3. Code Review beginner Multiple choice

    A team reviews small changes carefully and approves large ones within minutes. Why does defect detection collapse as a change grows, and which single intervention recovers the most of it?

    2 min answer code reviewdefect detectionbatch sizeattention
  4. Cohesion beginner

    Review this. An internal library called platform-common holds an HTTP client, a feature-flag reader, a money type, a retry helper and tenant-context propagation. 140 services depend on it. A one-line bugfix to the money type produces version 4.12.0, and until each service upgrades it is running a version missing the fix. The last upgrade wave took eleven weeks. What would you split, and what would you leave alone?

    3 min answer cohesionshared-librariesversioningrelease-cadence
  5. Architecture Communication beginner

    You have designed a system. Explain the same architecture to a CEO, an engineering manager and an engineer. What changes?

    2 min answer communicationstakeholdersinfluence
  6. Concurrency beginner Multiple choice

    A service handles 100 requests per second with a pool of 10 worker threads. The team raises the pool to 100 threads. Throughput stays at roughly 100 rps and p99 latency gets much worse. What is the primary reason?

    2 min answer concurrencylittles lawbottleneckthread pools
  7. Connection Pooling beginner

    Why does putting a connection pool in front of a database make a service faster when the database does exactly the same query work either way?

    3 min answer connection-poolingtls-handshakepostgresconcurrency
  8. Constrained Protocols beginner Multiple choice

    A metered NB-IoT fleet must not record a reading twice, because readings drive a customer's bill. The team proposes QoS 2 so the broker delivers each publish exactly once. Which choice fits better?

    2 min answer mqttqosidempotencynb-iot
  9. Constraint Thinking beginner

    A pipeline has four stages. Three run at about 30% utilisation and one runs at 95%. The team adds capacity to all four. Throughput barely moves. Why?

    2 min answer constraintsthroughputbottleneckqueueing
  10. Constraint Thinking beginner Multiple choice

    A team must ship a compliance-driven reporting system by a fixed statutory date nine months away. There are three engineers, no operations staff, an existing Postgres database, and no budget for new licences. Which constraint should drive the architecture?

    3 min answer constraintsoperabilityteam-sizeprioritisation
  11. Container Image Strategy beginner Multiple choice

    An inference service's container image is 6.2 GB because the model weights sit in the final layer. Autoscaling adds twelve fresh nodes at peak; the new pods stay NotReady for several minutes and other pods scheduled onto the same nodes wait behind them. What is happening and which change helps most?

    3 min answer container imagesimage pullcold startautoscaling
  12. Context Diagrams beginner

    A 40-engineer SaaS product has a context diagram with six external systems on it. Roughly how many outbound dependencies does a product that size actually have, how would you count them without guessing, and what does the real number change?

    3 min answer context diagramdependenciesinventoryvendors