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2988 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 areas2988 Architecture Fundamentals91 Distributed Systems111 Data Architecture100 Cloud Architecture97 Networking96 API & Integration Architecture97 Reliability & Resilience99 Observability92 Performance & Capacity Engineering100 Security Architecture105 Cost Architecture & FinOps102 Business Architecture103 Architecture Communication102 Enterprise Architecture100 Legacy Modernization102 AI-Era Architecture106 Software Architecture & Engineering93 Architecture Patterns94 Architecture Decision-Making101 The Architect's Meta-Skills102 Delivery & Release Engineering103 Platform Engineering & Developer Experience102 Testing & Quality Architecture102 Data Platform Architecture98 Streaming & Real-Time Data103 Data Governance & Semantics91 Frontend & Experience Architecture101 Edge, Mobile & IoT98 Regulatory & Data Protection Architecture99 Assurance, Audit & Model Risk98
Difficulty Any beginner intermediate advanced

3 questions in Delivery vs Maintainability.

  1. Delivery vs Maintainability intermediate

    A quick-commerce grocery operator running dark stores needs substitution handling for out-of-stock items. Option A is a rule table inside the existing order service: three weeks and it will need rework. Option B is a separate availability-and-substitution service with its own store: eleven weeks. The business does 45000 orders a day, cancels about 6% of them for stock reasons, expects the feature to recover roughly a third of those, and earns about 1.10 dollars of contribution per order. Roughly what is the cost of delay, and what rework budget does it justify?

    3 min answer cost-of-delaytechnical-debtsubstitutionsestimation
  2. Delivery vs Maintainability intermediate

    A team must ship a major capability quickly and the design that ships fastest is not the one that is easiest to maintain. How should the trade-off be made?

    1 min answer deliverymaintainabilityreversibilitydebt
  3. Delivery vs Maintainability intermediate

    Dropbox spent about four years rebuilding its desktop sync engine from scratch and shipped the replacement, Nucleus, to all users in 2020. The engineer who wrote it up said plainly that in many environments it would have been a terrible idea. What was true at Dropbox that made a four-year from-scratch rewrite the maintainable choice rather than the reckless one, and what did it cost?

    3 min answer dropboxrewriteinvariantstestability