Interview prompt
Problem context
A shared platform bill is growing 40% annually. Finance allocates cost by headcount, engineering blames platform overhead, and sales cannot tell whether large tenants are profitable. Design technical attribution and governance without pretending every byte has a perfect owner.
Skills being evaluated
cost attributionunit economicsshared-platform modelingincentive design
The full reasoning guide is part of Pro
The scenario and evaluation focus above remain public. Pro unlocks the structured answer, trade-off analysis, follow-up probes, common weak answers, rubric, related reasoning, and any architecture diagram.
Sign in to continueWhat the full guide covers
Clarify the decision
Establish scale assumptions
Functional and non-functional requirements
High-level architecture
Data model and flow
Consistency and transaction boundaries
Failure modes and recovery
Security and privacy
Observability and SLOs
Capacity and cost
Alternatives and trade-offs
Evolution and migration
What Staff and Principal candidates should emphasize