Technical practice
How would you integrate an AI capability into a production Java backend?
What to coverThe posting calls for AI capabilities in Java-based backend systems. Suggested preparation: explain service boundaries, failure handling, and how you would keep the integration reliable as usage grows.
How would you expose an AI capability through REST and GraphQL APIs?
What to coverThe role specifies API-first services using both REST and GraphQL. Suggested preparation: compare when each interface fits, and address request validation, response design, and the latency of AI-backed requests.
How would you design a retrieval-augmented generation pipeline with vector search?
What to coverThe posting names data pipelines for RAG and vector search. Suggested preparation: walk through document preparation, retrieval, generation, and how you would assess whether retrieved material improves answers.
How would you manage prompts and model orchestration in an LLM service?
What to coverPrompt design and model orchestration are stated responsibilities. Suggested preparation: describe how you would control changes, handle model failures, and balance answer quality against latency and cost.
How would you evaluate and troubleshoot a production AI service?
What to coverThe posting calls for evaluation and observability, with model monitoring listed as a nice-to-have. Suggested preparation: distinguish model-quality signals from service-health signals and explain how you would investigate a decline in either.
How would you choose AWS components for a scalable AI workload?
What to coverThe role names EC2, S3, RDS, Lambda, and EKS and emphasizes scalability, latency, reliability, and cost. Suggested preparation: compare suitable uses of those services for a hypothetical workload rather than assuming a specific Cornerstone architecture.
How would you deploy and operate a containerized AI service on EKS?
What to coverDocker, Kubernetes on EKS, and infrastructure as code with Terraform or AWS CDK are in the posting. Suggested preparation: cover deployment, scaling, recovery, and how you would keep infrastructure changes reproducible.
How would you select SQL and NoSQL stores for a distributed AI application?
What to coverThe role requires production SQL and NoSQL experience and trade-offs among consistency, availability, and performance. Suggested preparation: explain how access patterns and consistency needs would drive the choice.
When would you use an event-driven or asynchronous workflow rather than a synchronous request?
What to coverThe posting explicitly mentions event-driven and asynchronous architectures where appropriate. Suggested preparation: discuss latency, failure recovery, and how callers would learn the outcome of longer-running work.
How would you build a pipeline for feature engineering and inference?
What to coverThe role includes data pipelines supporting feature engineering and inference, alongside ML-driven workflows. Suggested preparation: explain how you would manage input quality, pipeline changes, and reliable delivery of inference results.
Behavioural practice
Tell me about a complex technical initiative you led from design into production.
What to coverThe Principal role owns multi-team initiatives end to end. Suggested preparation: use a real situation, explain your hands-on decisions and coordination, and state the outcome.
Describe a time you influenced an architecture decision or engineering standard across teams.
What to coverThe posting calls for influence through design reviews and technical guidance. Suggested preparation: describe the disagreement or decision, your actions, and the resulting change without overstating your authority.
Tell me about a time you mentored a senior engineer.
What to coverMentoring senior engineers is a stated responsibility. Suggested preparation: give the situation, the specific guidance you provided, and the observable result.
Describe a time you worked across product, data, UX, security, or DevOps to deliver a capability.
What to coverThe role explicitly involves collaboration with those functions. Suggested preparation: choose a real example, explain how you resolved differing priorities, and describe the delivery outcome.
Tell me about a production problem you owned through resolution.
What to coverThe posting emphasizes operating reliable systems, problem-solving, and end-to-end ownership. Suggested preparation: explain the situation, your diagnosis and actions, and what changed afterward.