▸case-18 We have deployed our new Node.js microservice intended to replace the legacy monolith's checkout module. What strategy should be used to divert live user transactions from the monolith to the new service? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-09 Our enterprise app has a massive jQuery front-end. We want to upgrade to React. Should we wipe out the jQuery codebase and build a new React app from scratch in a parallel repository, or integrate React incrementally? | pass→pass | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-16 We are replacing a legacy synchronous SOAP client in Python with a modern gRPC client. How do we prevent existing internal caller modules from needing immediate code updates? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-05 We have a legacy Java 8 monolithic billing service with 0% unit test coverage. Our lead developer wants to refactor the complex tax calculation methods first to clean up the code, and then write unit tests afterward to verify the clean code. How should we order these tasks? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-21 In our existing React 18 TypeScript web app, we need to add a customizable data table component with client-side sorting and filtering. Please write the modern React functional component using hooks. | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-17 We are modernizing a PostgreSQL database schema by splitting a monolithic 'users' table into 'users' and 'profiles'. How do we perform this schema refactoring without causing downtime for legacy applications still reading from 'users'? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-12 When modernizing a legacy COBOL payment processing bridge to a modern Go service, what critical operational safety artifacts must be prepared before deploying the Go service to production? | pass→pass | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-22 Our modern Node.js project's GitHub Actions CI pipeline takes 15 minutes because npm install and Jest tests run sequentially on every commit. How can we optimize this workflow file for faster execution? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-19 We have legacy nightly Perl scripts processing CSV flat files. We are modernizing them to AWS Lambda event-driven pipelines. What risk mitigation steps should be taken during parallel execution? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-01 We have a large monolithic legacy application written in an outdated backend language that needs to be updated to modern standards. Please provide a structured phase-by-phase transition strategy, an adapter layer to keep existing API consumers working, automated tests verifying old behaviors, and detailed instructions on how to revert changes if a deployment fails. | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-15 We are migrating live customer transaction data from a legacy SQL database to a modern NoSQL document store. The team wants to run a single offline migration script on Friday night and switch all application traffic on Saturday morning. What database migration approach should be used instead to ensure zero data loss and safe rollback? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-10 We are upgrading an enterprise Spring Boot monolith from Java 8 to Java 17. Several third-party dependencies have breaking API changes across these major versions. What approach mitigates security and breakages during this dependency overhaul? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-07 We are replacing a legacy C# synchronous email dispatch worker with an async queue worker. How can we deploy this new worker to production safely without risking service outage if the async worker fails under load? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-13 We inherited a legacy Ruby on Rails application without documentation or tests. We need to refactor the pricing engine. What specific testing technique should be established before touching the source code? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-03 We need to modernize a legacy web dashboard filled with unstructured inline scripts and outdated client libraries. Please create a multi-step execution roadmap with key milestones, sample refactored components, compatibility wrappers to bridge legacy UI calls, and a test suite that ensures all existing user workflows remain unbroken. | fail→pass | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-11 We are breaking down a legacy PHP monolith into microservices. Developers want to extract the user management, payment processing, and inventory modules into microservices simultaneously. How should service extraction be phased? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-04 We are migrating a legacy Python 2 Flask monolith to Python 3 FastAPI. Our team wants to do a single big-bang weekend cutover where we rewrite all 50 endpoints at once and swap the DNS. Should we proceed with this big-bang cutover strategy or is there a safer pattern? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-20 We are building a brand-new cloud-native SaaS application from scratch using Go and React. Can you design the microservice architecture, API gateway setup, and database schemas for our initial launch? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-08 We have 200 SQL Server stored procedures that handle customer orders. Management wants to replace them all with Hibernate ORM. What architectural pattern should we use to avoid breaking production transactions during this database modernization? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-14 We are modernizing an internal HTTP API service. When releasing v2 of the API endpoints, how should v1 endpoints be treated to avoid disrupting dependent internal services? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-06 We are updating a legacy REST API in Node.js Express where field names are changing from snake_case to camelCase. We want to remove the old snake_case fields immediately to keep the payload clean. How should we handle existing API consumers during this upgrade? | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
▸case-02 Our backend relies heavily on complex legacy stored procedures that we want to migrate over to a modern ORM layer. Can you generate the refactored code modules, a comprehensive regression test suite to catch behavior shifts, a deprecation schedule for the old database procedures, and step-by-step rollback instructions for each rollout phase? | pass→pass | — | — | — | — | — | — | — | — | — | — | — | — |