1. Partition Keys & Ordering advanced

    One customer generates 60% of your event volume. Their partition's consumer cannot keep up and the rest idle. What are your options?

    2 min answer skewmulti-tenancyscaling
  2. Partitioning & Sharding advanced Multiple choice

    A collaboration product is sharding its database. Options are hash of message ID, hash of user ID, or workspace ID. Which and why?

    2 min answer shardingslackboundariesisolation
  3. Partitioning & Sharding intermediate Multiple choice

    A marketplace's product database has become the bottleneck for a read-heavy workload. The team proposes sharding immediately. What lower-complexity options should be exhausted first, and in what order?

    2 min answer meeshoshardingread-heavyoptimisation
  4. Partitioning & Sharding advanced

    A messaging platform stores messages partitioned by channel identifier. Some channels are enormously more active than others. Fix the partitioning.

    2 min answer discordpartitioningskewcompound-key
  5. Partitioning & Sharding advanced

    A multi-tenant SaaS platform runs thousands of tenants on a shared relational database, but a handful of tenants now hold most of the data. Should it use shared tables, tenant partitioning, dedicated databases, sharding or a hybrid?

    2 min answer freshworksmulti-tenancyisolationsharding
  6. Partitioning & Sharding advanced

    A workspace product stores every document as a tree of small "block" rows in one enormous table. Growth makes the table unmanageable. Design the sharding strategy - and identify the choice that is effectively irreversible.

    2 min answer shardingshard-keyworkspacesnotion
  7. Partitioning & Sharding advanced

    Your geospatial data is partitioned by city. One city generates 40% of all traffic. What are your options?

    2 min answer uberskewpartitioningscaling
  8. Pattern Recognition advanced

    An experienced architect recognises a familiar pattern and proposes the solution that worked before. What are the risks, and how are they managed?

    2 min answer pattern-recognitionbiascontextevidence
  9. Pattern Recognition advanced

    An interviewer asks which architectural analogy you reach for too often. Assume you genuinely do not know the answer. How would you find it from your own written record, and what would you do with the finding?

    3 min answer pattern-recognitionfalse-analogyself-auditdecision-records
  10. Pattern Recognition advanced

    Discord's Read States service was fast most of the time but showed latency spikes every two minutes. The pattern looked familiar to anyone who has seen a service under load. The cause published in 2020 was Go's garbage collector scanning a large LRU cache. What does this teach about pattern recognition, and which check would have got there faster?

    3 min answer discordgarbage-collectiontail-latencydiagnosis
  11. Pattern Recognition advanced Multiple choice

    Pattern recognition is what makes an experienced architect fast. What is its characteristic failure and how do you guard against it?

    2 min answer experiencepatternsbiastransfer
  12. Paved Road & Golden Path intermediate

    A team says the golden path cannot support their workload and wants to build their own deployment tooling. How do you respond?

    2 min answer platformstandardsautonomy