InterviewsVector
AdvancedStaffData Architecture & Consistency55 minutesPro answer

SDV-010

Move a transaction boundary after splitting a business domain

Preserve money and inventory invariants when a formerly local transaction spans independently deployed services and retries become normal.

Distributed TransactionsConsistencyEvent DrivenReconciliation

Interview prompt

Problem context

Orders, inventory, and payments currently commit in one relational transaction. Teams want independent ownership and scale, but splitting the database makes partial success possible. Customers must not be charged for permanently unavailable inventory, and every state must be explainable to support.

Skills being evaluated

invariant decompositionsaga designidempotencyoperational state modeling

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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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