▸case-01 We are re-architecting our core financial ledger platform to support balance lookups at any arbitrary past timestamp and maintain an unalterable audit log. Please draft a complete architectural blueprint for this system. The document should define the core aggregate boundaries, detail the event stream layout, outline how optimized read models will be populated for fast balance queries, and specify a performance strategy for long-lived streams. | fail→fail | 47,436 | 47,465 | +0% | 1 | 1 | 0% | 8,268 | 6,985 | -16% | 0 | 0 | — |
▸case-02 Our e-commerce platform needs a resilient checkout flow involving inventory reservation, payment processing, and order fulfillment. We must handle payment failures gracefully using compensating steps across microservices without relying on distributed transactions. Please produce a technical specification detailing the command-query separation, the event structure across domain boundaries, and an orchestration model that guarantees resilient cross-aggregate workflow execution. | fail→fail | 44,220 | 30,639 | -31% | 1 | 1 | 0% | 8,260 | 6,211 | -25% | 0 | 0 | — |
▸case-03 We are building a standard user contact directory microservice storing user profiles, email addresses, and preferences with low write volume and strict PostgreSQL table constraints. Draft a RESTful API data model and database schema for managing user profiles using standard relational tables. | pass→pass | 23,007 | 22,941 | -0% | 1 | 1 | 0% | 4,807 | 5,144 | +7% | 0 | 0 | — |
▸case-04 We are integrating a third-party payment processing API that requires immediate synchronous approval before completing a transaction. Draft a synchronous REST client service implementation that enforces immediate atomic authorization responses. | pass→pass | 20,986 | 19,464 | -7% | 1 | 1 | 0% | 3,779 | 4,176 | +11% | 0 | 0 | — |
▸case-05 We need to design a static data warehouse schema in Snowflake for nightly batch reporting on historical sales summary totals using standard dimensional modeling (star schema). Provide the SQL DDL statements for the dimensions and fact tables. | pass→pass | 20,059 | 18,212 | -9% | 1 | 1 | 0% | 3,938 | 4,329 | +10% | 0 | 0 | — |
▸case-06 When consuming MoneyTransferred events in our Apache Kafka account balance read-model projection microservice, network retries might deliver duplicate messages. We plan to sum incoming event amounts directly into the PostgreSQL balance row. Produce a resilient handler design to update balance projections accurately. | fail→fail | 23,083 | 20,865 | -10% | 1 | 1 | 0% | 3,941 | 4,205 | +7% | 0 | 0 | — |
▸case-07 A customer requested hard deletion of their account history under privacy regulations. Our operations team proposes executing a SQL DELETE query directly against the production EventStoreDB tables. Provide a compliant architectural strategy for handling right-to-be-forgotten requests in an event store. | pass→pass | 24,050 | 29,524 | +23% | 1 | 1 | 0% | 3,561 | 4,561 | +28% | 0 | 0 | — |
▸case-08 Our aggregate stream for long-running trading accounts in EventStoreDB contains over 50,000 historical events, causing aggregate rehydration during command processing to take several seconds. Model an optimized aggregate rehydration architecture. | pass→pass | 22,680 | 26,211 | +16% | 1 | 1 | 0% | 3,605 | 5,004 | +39% | 0 | 0 | — |
▸case-09 We need to update our read model projection schema in PostgreSQL to add a new calculated customer tier column. Developers suggest dropping and rebuilding the production projection table directly while live traffic flows through. Provide an operational deployment plan for updating projection read models. | fail→pass | 19,944 | 16,170 | -19% | 1 | 1 | 0% | 3,333 | 3,232 | -3% | 0 | 0 | — |
▸case-10 We need to add a mandatory tax_jurisdiction attribute to our OrderPlaced event payload in Apache Pulsar, but legacy consumers still process version 1 events without this field. Developers proposed updating old JSON records directly in the event database. Design a backward-compatible event versioning strategy. | pass→pass | 19,762 | 18,262 | -8% | 1 | 1 | 0% | 3,392 | 3,851 | +14% | 0 | 0 | — |
▸case-11 Our distributed order fulfillment system logs errors independently across six microservices, making it impossible to trace the cascade of events triggered by a single customer purchase. Outline the event envelope structure to solve cross-service observability. | pass→pass | 17,062 | 19,252 | +13% | 1 | 1 | 0% | 3,081 | 4,011 | +30% | 0 | 0 | — |
▸case-12 Our travel booking saga coordinates flights, hotels, and car rentals across microservices. If the saga host process crashes mid-execution during payment confirmation, compensating events fail to dispatch. Propose a resilient framework architecture for saga orchestration. | pass→pass | 24,785 | 22,119 | -11% | 1 | 1 | 0% | 3,950 | 4,454 | +13% | 0 | 0 | — |
▸case-13 Developers are putting complex SQL JOIN queries into our domain aggregate command handlers to calculate reporting metrics prior to accepting orders. Provide a clean CQRS architectural separation for command processing and query reporting. | pass→fail | 19,571 | 20,798 | +6% | 1 | 1 | 0% | 3,223 | 3,904 | +21% | 0 | 0 | — |
▸case-14 A team is creating a single event stream named SystemEvents in Redis Stream containing every domain change for users, invoices, orders, and inventory across the entire enterprise. Recommend an aggregate boundary and stream design strategy. | fail→pass | 19,015 | 18,094 | -5% | 1 | 1 | 0% | 3,077 | 3,433 | +12% | 0 | 0 | — |
▸case-15 An auditor needs to verify access rights in an enterprise portal as they existed on December 31st at 11:59 PM. The database team suggests taking manual daily full database dumps. Provide an event sourcing strategy to serve temporal state queries. | fail→pass | 21,002 | 21,285 | +1% | 1 | 1 | 0% | 3,433 | 4,371 | +27% | 0 | 0 | — |
▸case-16 A customer account balance was over-credited due to a promotion glitch. The operations team wants to directly update the balance column in the production database table to fix it. Design an architectural pattern to correct historical balance errors in an event-sourced ledger. | pass→pass | 17,895 | 17,767 | -1% | 1 | 1 | 0% | 2,998 | 3,462 | +15% | 0 | 0 | — |
▸case-17 Querying historical event streams directly for user dashboard displays in Elasticsearch is causing high latency and timeout errors under heavy read traffic. Design an optimized query layer architecture. | pass→pass | 20,268 | 23,214 | +15% | 1 | 1 | 0% | 3,200 | 3,879 | +21% | 0 | 0 | — |
▸case-18 In an event-driven supply chain system using RabbitMQ, network latency causes ShipmentDelivered events to occasionally arrive before ShipmentDispatched events at the projection consumer. Design a resilient sequence handling mechanism. | pass→pass | 25,703 | 26,289 | +2% | 1 | 1 | 0% | 4,358 | 5,348 | +23% | 0 | 0 | — |
▸case-19 A microservice writes aggregate updates to MySQL tables and then sends events to RabbitMQ in a separate non-transactional block, leading to ghost events on failed database commits. Design an architecture ensuring reliable event publishing. | fail→pass | 19,808 | 22,804 | +15% | 1 | 1 | 0% | 3,295 | 4,369 | +33% | 0 | 0 | — |
▸case-20 A developer plans to update PostgreSQL tables and publish to Apache Kafka simultaneously inside an HTTP POST controller method. Explain the system risk and provide the event sourcing architectural replacement. | pass→pass | 18,243 | 20,358 | +12% | 1 | 1 | 0% | 3,113 | 3,859 | +24% | 0 | 0 | — |
▸case-21 A complex bug in our order processing engine occurred in production. Developers want to replicate the exact state transitions that led to the failure. Detail how to utilize event streams for root-cause analysis. | pass→pass | 18,471 | 19,905 | +8% | 1 | 1 | 0% | 3,042 | 3,727 | +23% | 0 | 0 | — |
▸case-22 Two parallel HTTP requests attempt to withdraw money from the same account aggregate in EventStoreDB at the exact same millisecond. Developers propose using pessimistic database row locks on read models. Provide an event store concurrency control mechanism. | pass→pass | 13,850 | 16,008 | +16% | 1 | 1 | 0% | 2,573 | 3,261 | +27% | 0 | 0 | — |
▸case-23 An EventStoreDB cluster table has grown to 500 million rows across 10 years, increasing storage costs and slowing snapshot rebuilding. Detail a tiered storage architecture for long-lived event stores. | pass→pass | 26,668 | 22,918 | -14% | 1 | 1 | 0% | 4,173 | 3,979 | -5% | 0 | 0 | — |
▸case-24 We need to ensure that appending multiple domain events representing a single business transaction occurs atomically in our custom database event store implementation. Provide the required persistence guarantees. | pass→pass | 17,235 | 20,711 | +20% | 1 | 1 | 0% | 2,733 | 4,023 | +47% | 0 | 0 | — |