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.
8 questions
2 complete public walkthroughs
#017Locked
Contain cascading failures across services that share hidden dependencies
Find common pools and retry amplification, then design bulkheads, deadlines, admission, and recovery that contain a dependency slowdown.
IntermediateReliability50 min
Blast RadiusReliabilityLoad Shedding
#018Locked
Plan regional evacuation with explicit RPO, RTO, and authority transfer
Turn “multi-region” into a rehearsed evacuation protocol with data-loss bounds, capacity, fencing, dependency readiness, and return-home criteria.
AdvancedReliability55 min
Disaster RecoveryActive ActiveRollback
#019Locked
Design safe rollback across application, schema, and event contracts
Make rollback a compatibility protocol for mixed versions and irreversible data effects, not a button that redeploys old binaries.
AdvancedReliability55 min
RollbackSchema EvolutionEvent Driven
#020Locked
Eliminate a retry storm during a long partial outage
Coordinate deadlines, retry ownership, budgets, jitter, hedging, and durable deferral so recovery traffic cannot outnumber original demand.
AdvancedReliability50 min
ReliabilityLoad SheddingIncident Response
#021Locked
Recover from disaster when backups exist but restores are unproven
Design verifiable backup, restore, dependency reconstruction, and business prioritization when current recovery confidence is mostly theoretical.
AdvancedReliability65 min
Disaster RecoveryAuditabilityIncident Response
#022Locked
Design a controlled brownout mode customers can understand
Translate product value and system cost into degradation levels, safe activation, truthful user messaging, and measured fallback quality.
AdvancedReliability60 min
Load SheddingReliabilitySlo
#023Locked
Set dependency failure budgets across teams with different incentives
Allocate reliability expectations through a dependency graph without pretending service-level SLOs compose automatically or using budgets as blame.
AdvancedReliability65 min
Error BudgetsSloOrganizational Design
#024Locked
Build a chaos program that produces evidence instead of theater
Create hypothesis-driven resilience experiments with safety controls, production relevance, learning ownership, and portfolio-level risk reduction.
ExpertReliability75 min
ReliabilityIncident ResponseBlast Radius
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.