InterviewsVector
IntermediateSeniorPerformance, Observability & Capacity50 minutesPro answer

SDV-048

Define SLOs and error-budget policy for a product with unequal journeys

Choose customer-centered indicators, windows, targets, and policy actions without averaging away critical tenants or turning SLOs into vanity dashboards.

SloError BudgetsObservabilityOrganizational Design

Interview prompt

Problem context

A collaboration product reports 99.95% API availability, yet enterprise customers complain about delayed sync and failed document saves. Teams measure different endpoints and no release decision changes when targets are missed. Define useful SLOs and an error-budget operating policy.

Skills being evaluated

SLI designtarget calibrationerror-budget policystakeholder alignment

The full reasoning guide is part of Pro

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What 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

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