ZorixOS
3+ DeltaX questions

DeltaX interview questions and how to prepare

The questions candidates report from DeltaX interviews, sorted by how often they come up, with difficulty and topics, plus original practice written in DeltaX's interview style.

Practice DeltaX questions free All companies

ZorixOS tracks 3 community-reported DeltaX interview questions, drawn from an open-source dataset of real interview reports and sorted by how frequently each one comes up. Every question links to its source. Alongside them are 78 original ZorixOS practice questions written in DeltaX's known interview style (not claimed as asked at DeltaX), so you can rehearse the real format. Practice any of them out loud in a free AI mock interview tuned to DeltaX.

Updated July 2026

DeltaX interview questions candidates report

Community-reported from real DeltaX interviews (open-source dataset), most-asked first. Showing 3. Each links to its source.

  1. Roman to Integer
    Hash TableMathString
    Easy100% asked
  2. Bus Routes
    ArrayHash TableBreadth-First Search
    Hard83% asked
  3. Different Ways to Add Parentheses
    MathStringDynamic ProgrammingRecursion
    Medium83% asked

Practice questions in DeltaX's style

Original ZorixOS questions written the way DeltaX interviews, so you rehearse the real format. Not claimed as asked at DeltaX.

  1. Design a low-latency real-time bidding (RTB) system for DeltaX that integrates with multiple ad exchanges. Detail the key components, data flow, latency requirements, and strategies for achieving high scalability and reliability under peak load.

    Software EngineerSystem DesignTests: Evaluates knowledge of distributed systems, real-time processing, and ad-tech architecture at scale.

  2. A DeltaX client's ad campaign is consistently overspending its daily budget by 15-20% despite the configured pacing algorithm. Describe your debugging approach, potential root causes within an ad-tech system (e.g., bidding logic, data synchronization, external API issues), and how you would implement a fix.

    Software EngineerDebuggingTests: Assesses problem-solving skills, understanding of ad-tech mechanics, and debugging methodology.

  3. DeltaX needs to ingest campaign performance data (impressions, clicks, conversions) from 50+ different ad networks, each with unique API structures, authentication mechanisms, and data schemas, at a volume of billions of records daily. Design a robust, scalable, and fault-tolerant data ingestion pipeline.

    Software EngineerSystem DesignTests: Checks understanding of data pipeline architecture, API integration challenges, and ETL at scale.

  4. Implement a function `select_optimal_creative(user_profile, available_creatives, optimization_goal)` that, given a user's profile (e.g., demographics, interests) and a set of ad creatives, selects the most relevant creative. Assume a simplified scoring mechanism based on keyword matching, user engagement history, and a client-defined `optimization_goal` (e.g., 'maximize_ctr', 'maximize_cvr').

    Software EngineerCodingTests: Examines coding proficiency, ability to model real-world problems, and understanding of basic recommendation/matching logic.

  5. Design a real-time system for DeltaX to detect and flag common types of ad fraud (e.g., bot traffic, click farms, impression stuffing) across billions of daily ad impressions. What features would you collect, what detection methods would you employ, and how would you minimize false positives in a high-throughput environment?

    Software EngineerSystem DesignTests: Tests knowledge of anomaly detection, real-time data processing, and security/anti-fraud measures in ad-tech.

  6. A key advertiser using DeltaX reports significant delays in their ad serving, leading to missed impression opportunities and under-delivery. Outline your investigation process, identifying common latency bottlenecks in a programmatic ad-tech stack (e.g., DNS, CDN, bidding logic, external API calls), and propose solutions.

    Software EngineerDebuggingTests: Assesses diagnostic skills, understanding of network and system performance, and ad-tech operational challenges.

72+ more DeltaX-style questions are in the free library, each practiceable live with adaptive follow-ups and an honest scorecard. Start free.

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DeltaX Interview Questions (2026) | ZorixOS