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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

91 questions in Architecture Decision-Making.

  1. SQL vs NoSQL advanced

    A platform must choose between a relational database and a wide-column store for its highest-volume data. What decides it, and what is the common error?

    2 min answer sqlnosqlaccess-patternspartition-key
  2. SQL vs NoSQL advanced

    A startup with a few thousand users is choosing between a single-region Postgres and a geo-distributed serializable database. What evidence should drive the decision, and what would trigger revisiting it?

    3 min answer cockroachdbpostgresdistributed-sqlreversibility
  3. SQL vs NoSQL intermediate

    A team proposes a document database for an order management system because "orders are documents". Assess.

    2 min answer datastoredecisionmodelling
  4. SQL vs NoSQL advanced

    By 2021 Notion's single Postgres database had reached the point where VACUUM stalled and transaction ID wraparound became a genuine risk. They sharded Postgres into 480 logical shards rather than moving block data to a NoSQL store. What forced the change, what decided the destination, and where would copying it be a mistake?

    2 min answer notionpostgresshardingvacuum
  5. SQL vs NoSQL advanced Multiple choice

    Figma's Postgres stack grew roughly 100x between 2020 and 2024. The team had already partitioned tables vertically and now needed horizontal scale for the largest tables. They evaluated distributed SQL engines including CockroachDB and TiDB and rejected all of them, then spent about nine months building their own sharding layer with a query proxy written in Go. Which fact best explains that choice?

    2 min answer figmapostgresshardingtechnology-selection
  6. Sync vs Async advanced

    A checkout flow makes 9 synchronous calls: inventory, pricing, tax, fraud, payment, loyalty, shipping, notification and analytics. What would you change?

    2 min answer checkoutcouplingavailabilitylatency
  7. Sync vs Async intermediate

    A team debates whether an operation should be synchronous or asynchronous. What decides it, and what is the cost of getting it wrong in each direction?

    2 min answer linearsyncasyncuser-experience
  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. Sync vs Async advanced

    An order API calls six services synchronously and takes 3 seconds at p95, failing whenever any dependency is degraded. Redesign it.

    2 min answer asyncavailabilityeventsoutbox
  10. Sync vs Async intermediate Multiple choice

    Order service must notify inventory, billing and notifications when an order is placed. Synchronous calls or events? Justify.

    2 min answer couplingmessagingdesign
  11. Sync vs Async intermediate

    Where should the boundary between synchronous and asynchronous processing sit in an API platform, and what determines it?

    2 min answer syncasynclatencyacknowledgement
  12. Technology Selection intermediate

    A team is selecting a technology for a new component. What should the evaluation include beyond technical fit?

    2 min answer technology-selectionoperabilityecosystemexit