Case studies · 16
Each case has a prompt, concepts it tests, and the evaluation lens interviewers use. Click to open the full walkthrough.
Design a content moderation system for a large social product that classifies policy violations, routes uncertain cases to human review, supports appeals, and adapts to adversarial behavior.
Concepts tested
Evaluation lens
Design a demand forecasting platform that predicts future demand by product, geography, and time window for inventory, staffing, or pricing decisions.
Concepts tested
Evaluation lens
Design a system that ingests heterogeneous enterprise documents (PDFs, scans, spreadsheets, emails) and produces structured fields with confidence scores, routing low-confidence outputs to human review.
Concepts tested
Evaluation lens
Design a marketplace matching system for buyers and sellers, riders and drivers, freelancers and jobs, or candidates and recruiters.
Concepts tested
Evaluation lens
Design a multi-tenant AI platform that supports RAG, tools, evals, and model routing for multiple internal product teams or enterprise customers.
Concepts tested
Evaluation lens
Design a personalized video home feed that maximizes long-term engagement with strong watch time, diversity, and freshness while keeping serving latency under 300ms.
Concepts tested
Evaluation lens
Design a notification ranking system that chooses which notifications to send, when to send them, and which channel to use while protecting long-term user trust.
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Evaluation lens
Design a payment fraud detection system that scores transactions in real time under tight latency and review-cost constraints, balancing fraud recall against legitimate-customer friction.
Concepts tested
Evaluation lens
Design a search ranking system for a marketplace where users type free-form queries and the engine must return the most relevant listings under a 200ms p99 latency budget.
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Design a migration from a legacy XGBoost prediction service to a new feature store and model-serving platform with zero downtime.
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Design a click-through-rate prediction system that ranks ads in a real-time auction with strict latency, calibrated probabilities, and clear revenue trade-offs.
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Evaluation lens
Design an LLM-based customer support agent that can answer questions, take limited actions (refunds, status updates), escalate when uncertain, and log every step for audit.
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Design an anomaly detection platform that monitors many time series or events, alerts responders, learns from feedback, and controls false positives.
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Evaluation lens
Design an internal enterprise knowledge assistant that retrieves trusted documents, cites sources accurately, respects per-user access controls, and meets a 3-second p95 latency budget.
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Design an internal evaluation platform that gates LLM-powered features at release time, catches silent regressions across prompt and model changes, and serves multiple product teams with different requirements.
Concepts tested
Evaluation lens
Design cold-start personalization for a marketplace where new users, new items, and new sellers need useful exposure before collaborative signals exist.
Concepts tested
Evaluation lens