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ORIGINAL SYSTEM DESIGN QUESTION

Evidence-based support case routing

Route incoming support cases to qualified agents while preserving case history.

Open practice workspace

Original exercise · foundation. Editorial role relevance does not imply a company has asked this question.

Requirements and constraints

  • 100,000 cases/day; 2,000 agents; priority cases need assignment within two minutes.
  • Model suggestions must not overwrite agent decisions; private attachments need access controls.
  • State assumptions and justify security, cost, operational ownership and data retention.

Pressure round

An agent goes offline after a high-priority case is assigned.

Build and explain the design

Requirements & scope

Who uses it? What must it do? What is explicitly out of scope? State latency, durability and privacy goals.

Self-review guidance

Define the actors, required operations and out-of-scope behavior. Explicit requirement: Model suggestions must not overwrite agent decisions; private attachments need access controls.

Capacity estimates

State assumptions, peak requests/second, data volume and retention. Show your arithmetic and units.

Self-review guidance

Use this workload: 100,000 cases/day; 2,000 agents; priority cases need assignment within two minutes. Convert rates and payload sizes into peak compute/storage assumptions; show units, headroom and what remains unmeasured.

APIs & data model

Describe endpoints/events, entity keys, indexes, authorization, and idempotency.

Self-review guidance

Define case events, skill/availability records, assignment leases and overrides.

Architecture & data flow

Describe components and request/event paths. Use plain text arrows to sketch your design; explain each responsibility.

Self-review guidance

Separate intake, routing suggestions, assignment authority and review queues.

Failures & observability

What happens on overload, duplicate events, partial failures or lost dependencies? Discuss monitoring and recovery.

Self-review guidance

Pressure-test: An agent goes offline after a high-priority case is assigned. Describe bounded recovery, deduplication, observability and a user-visible failure state.

Tradeoffs & alternatives

Compare two plausible approaches. State the costs, consistency model and what would make you change the design.

Self-review guidance

Compare automatic reassignment with ownership continuity and user-visible status.

Design guidance describes assumptions and tradeoffs; no architecture has been simulated or benchmarked.

Practice this question

Save your work privately, explain decisions and return to your revision queue.

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