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Page 9 of 26
Places contract, use-case, domain, authorization, and database validation at the boundaries that can enforce each rule consistently.
Design list endpoints with pagination, filtering, sorting, limits, and database-aware performance behavior.
Uses read replicas selectively while accounting for stale reads, read-after-write behavior, routing, failover, query cost, and replication health.
Design request DTOs that protect API contracts from domain and persistence models.
Uses unique namespaces and correctly scoped fixtures so parallel tests improve speed without creating collisions.
Treats flakiness as an observable defect in timing, state, order, infrastructure, or product behavior.
Diagnoses hidden per-row EF Core queries and replaces them with a bounded query shape without creating an oversized join.
Explains a telemetry-driven path from slow endpoint symptoms to database, cache, dependency, CPU, or payload root cause.
Decide whether Azure SQL errors are transient platform faults or a real application/query regression.
Treats JSON serialization settings and DTO shape as a public contract, including naming, enums, nulls, converters, compatibility, and tests.
Frames a vague system-design problem with explicit flows, constraints, scale estimates, and measurable quality targets before selecting components.
Explain how a .NET BackgroundService should handle cancellation, in-flight work, and application shutdown.
Explains initial incident triage: confirm impact, mitigate, assign roles, preserve evidence, and communicate.
Shows how publisher-to-subscriber references can retain objects and how to clean up event-based lifetimes.
Focuses on ToList chains, collection capacity, repeated enumeration, and memory-aware data shaping.
Explains a practical approach to diagnosing failed builds, tests, package restore, environment issues, or flaky checks.
Explains transient database errors, retry strategy, EF Core execution strategy, idempotency, timeouts, and avoiding retry storms.
Covers deployment logs, startup failures, runtime stack, app settings, missing files, Key Vault references, and post-deployment diagnosis.
Frames allocation reduction as measurement-driven API work rather than premature micro-optimization.
Builds a story about improving code quality incrementally while still delivering product value.
Explains how to triage post-release 500 errors using deployment correlation, logs, traces, feature flags, and rollback safety.
Explains how to diagnose 401/403 spikes across token validation, identity provider issues, clock skew, deployment changes, and abuse.
Explains when to store large payloads outside the broker and pass references through messages.
Design a bounded-concurrency approach for calling an external API safely from .NET code.