Trade-off discipline
State what wins, what loses, and which new evidence would reverse the choice.
Architecture Judgment Index
75 system design decisions beyond the standard question bank
Built for Staff, Principal, Architect, and senior engineering leadership interviews. Practice ambiguous trade-offs, migrations, blast-radius reasoning, multi-region consistency, cost, security, and the judgment behind an architecture review.
75
original questions
10
decision domains
2
complete samples
35–90m
interview depth
10 Senior · 30 Staff · 25 Principal · 10 Distinguished
What the interview is really testing
Architecture judgment under incomplete information
These are not component-recitation prompts. Each scenario forces a candidate to identify the decision, make assumptions explicit, protect invariants, plan failure and recovery, price the options, and lead a realistic change from the system and organization that already exist.
Failure and recovery
Define blast radius, degraded behavior, reconciliation, rollback, and operational proof.
Evolutionary delivery
Move from the current architecture through observable, reversible stages instead of a flag day.
Staff-level influence
Connect technical decisions to ownership, incentives, cost, policy, and cross-team execution.
Coverage
Ten decision domains
Balanced across distributed systems, data, reliability, platform, security, performance, evolution, economics, and leadership.
Distributed Systems & Scale
Partitioning, coordination, overload, state movement, and blast-radius decisions in mature distributed systems.
Data Architecture & Consistency
Transaction boundaries, online migrations, residency, backfills, reconciliation, and truthful derived data.
Reliability, Resilience & Recovery
Cascades, brownouts, rollbacks, regional evacuation, disaster recovery, and measurable dependency risk.
APIs, Events & Integration
Long-lived contracts, event evolution, partner workflows, delivery semantics, acquisitions, and global fairness.
Cloud Infrastructure & Platforms
Paved roads, control planes, deployments, identity, scheduling, capacity, and governed self-service platforms.
Security, Privacy & Multi-Tenancy
Isolation boundaries, key management, deletion, zero trust, side channels, audit evidence, and privileged access.
Performance, Observability & Capacity
Tail latency, SLO policy, telemetry economics, uncertain demand, workload isolation, and silent failure detection.
Architecture Evolution & Migrations
Monolith evolution, stranglers, protocol changes, ownership boundaries, debt portfolios, and reversible decompositions.
Cost & Operational Efficiency
Reliability-aware savings, unit economics, tiering, build-versus-buy, carbon, egress, and commitment risk.
Architecture Leadership & Decisions
Decision quality, cross-team alignment, compliance trade-offs, program recovery, platform retirement, and impact.
7 questions
2 complete public walkthroughs
#062Locked
Reduce infrastructure cost without spending the reliability margin twice
Find waste through unit economics, then protect failure headroom, rollback capacity, and customer SLOs with staged savings and explicit guardrails.
IntermediateCost & Operations50 min
Cloud CostReliabilityCapacity Planning
#063Locked
Allocate shared cloud cost to products and tenants without false precision
Design activity-based cost units, shared-capacity allocation, uncertainty, and behavioral feedback that teams trust enough to act on.
AdvancedCost & Operations55 min
Cloud CostMulti TenancyGovernance
#064Locked
Optimize storage tiers when compliance and recovery pull in opposite directions
Place hot, warm, cold, and deleted data by access, recovery, legal, and security semantics rather than age alone.
AdvancedCost & Operations55 min
Cloud CostComplianceDisaster Recovery
#065Locked
Choose build versus buy for a capability that can become existential
Evaluate strategic differentiation, concentration risk, control, operating skill, contract leverage, and reversible adoption for a critical dependency.
AdvancedCost & Operations55 min
Build Vs BuyVendor StrategyReliability
#066Locked
Shift batch workloads with carbon-aware scheduling without missing deadlines
Move flexible computation across time and approved regions using auditable carbon signals, deadlines, data gravity, and reliability constraints.
AdvancedCost & Operations60 min
Capacity PlanningCloud CostData Residency
#067Locked
Control cloud egress cost without trapping data or weakening recovery
Reduce cross-zone and provider traffic through placement, compression, caching, contracts, and architecture while preserving portability and failover.
AdvancedCost & Operations60 min
Cloud CostVendor StrategyData Residency
#068Locked
Reserve capacity under volatile demand and uncertain product strategy
Build a commitment portfolio across base, burst, options, and scarce hardware while demand, architecture, and regional strategy may all change.
ExpertCost & Operations75 min
Capacity PlanningCloud CostVendor Strategy
Build the primitives behind the decisions
Pair the index with InterviewVector's Distributed Systems field manual, system design case studies, and the AI Architect track.