1. Software Architecture advanced

    A commerce platform runs a very large monolith serving enormous traffic and chooses not to decompose it into microservices. What must be true for that to be the right choice?

    2 min answer monolithmodularityboundariesscale
  2. Software Architecture advanced

    Knight Capital lost roughly $460M in 45 minutes in 2012 after a deployment reached seven of eight servers. Which architectural failures made that possible, and which one would you fix first?

    2 min answer deploymentfeature-flagskill-switchcase-study
  3. Software Architecture advanced

    Uber reached roughly 2,200 microservices and found the estate incomprehensible. Their fix was not consolidation. What was it, and why does it generalise?

    2 min answer case-studyubermicroservicesboundaries
  4. Software Architecture advanced

    You need to ship a rewrite of the pricing engine. Same inputs, same expected outputs, completely new implementation. How do you release it?

    2 min answer releasecanarytestingrisk
  5. Contract Tests advanced Multiple choice

    A developer-tools vendor of JetBrains' shape publishes a plugin API used by several thousand third-party plugins it does not control and cannot enumerate. An architect proposes consumer-driven contract tests. Which approach actually protects a release?

    3 min answer contract testingpublic apipluginsreplay
  6. Contract Tests advanced

    Consumer-driven contract testing is technically sound but adoption stalls. What organisational conditions does it require?

    2 min answer contract-testingadoptionincentivesscope
  7. Contract Tests intermediate

    How does contract testing let two teams deploy independently, and what does it not tell you?

    2 min answer contract-testingdeploymentverificationlimits
  8. SOLID intermediate

    A reviewer rejects a change for violating the single responsibility principle. When is that a substantive objection and when is it cargo cult?

    2 min answer supabasesolidprinciplesreview
  9. SOLID beginner

    After a refactor replaced a list implementation with an immutable one, a nightly job starts failing with an unsupported-operation error on a line nobody has edited in two years. Every type matches and the compiler was happy. What broke, and what is the design fix?

    2 min answer liskovinterface segregationcontractssilent failure
  10. SOLID intermediate Multiple choice

    Which SOLID principle has genuine architectural consequences, and which one most often produces harm?

    2 min answer soliddependency-inversionpremature-abstractiondesign
  11. SOLID intermediate

    Which SOLID principle produces the most practical benefit in a large codebase, and which is most often misapplied?

    2 min answer soliddependency-inversionabstractionover-engineering
  12. Technical Debt intermediate

    A team's backlog contains fifty technical debt items. How should they be triaged, and which category is most often mis-sorted?

    2 min answer chargebeetechnical-debtprioritisationinterest