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Google·Software Engineer·Onsite - Coding / Algorithms·Junior

JuniorPending
Sep 2026Remote

Summary

Got recruited by Google for an SWE role after a LinkedIn inmail, made it through the behavioral assessment and online coding challenge, then ran out of time in the first technical interview after spending too long on intro questions and not being able to code up a backtracking solution. Googleyness round still pending, so the verdict isn't in yet.

Questions Asked (4)

Q1

Walk me through your background and what you've been working on.

Adaptability & Ambiguity
Author's notes

Burned a solid 10 minutes here between the intro and the AI usage question that followed.

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AI HintsAI Generated

Suggested Approach

Structure your answer as a concise narrative that connects your past experiences to the role's requirements, emphasizing adaptability and comfort with ambiguity. Highlight specific projects where you navigated unclear problems, and tie them to the skills Optiver values in data scientists.

Pro tip: Quantify your impact wherever possible (e.g., 'reduced latency by 30%') and explicitly mention how you thrived in ambiguous situations, as Optiver is a trading firm that values quick, data-driven decisions under uncertainty.

1. Brief Introduction

Start with a one-sentence summary of your current role and years of experience, setting the stage for your narrative.

2. Educational & Early Career Highlights

Mention relevant degrees, certifications, or early projects that built your foundation in data science, focusing on analytical and problem-solving skills.

3. Key Projects & Achievements

Describe 2-3 significant projects, emphasizing the problem, your approach, and measurable outcomes. Choose examples that showcase adaptability to new domains or ambiguous requirements.

4. Connection to Optiver

Explicitly link your background to Optiver's needs, such as experience with real-time data, financial modeling, or working in fast-paced environments.

5. Recent Focus & Future Interest

Summarize what you've been working on recently and express enthusiasm for applying your skills to challenges in trading and market making.

Key Points to Mention

  • Experience with ambiguous or undefined problems and how you brought structure to them
  • Technical skills: Python, SQL, machine learning, statistical modeling, and data visualization
  • Projects involving large datasets, real-time analytics, or financial data
  • Collaboration with cross-functional teams (e.g., engineers, traders, product managers)
  • Quantifiable results (e.g., improved model accuracy, reduced processing time)
  • Adaptability to new tools, domains, or changing requirements

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.

Q2

How do you use AI tools in your day-to-day development and debugging work?

Adaptability & AmbiguityTechnical Trade-offs
Author's notes

This was apparently a required GenAI fluency check, not just small talk.

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AI HintsAI Generated

Suggested Approach

Frame your answer around a specific, recent example where AI tools accelerated your development or debugging process, emphasizing how you validated AI output and integrated it into your workflow. Highlight both the benefits and the limitations you've encountered, showing that you use AI as a force multiplier rather than a crutch. Connect your approach to Google's values of user focus, speed, and technical rigor.

Pro tip: Emphasize that you always treat AI-generated code as a starting point, not a final solution—demonstrate your ability to critically evaluate and test AI suggestions, which aligns with Google's emphasis on code quality and reliability.

1. Set the Context

Briefly describe your current role and the types of development/debugging tasks you handle, so the interviewer understands your baseline.

2. Share a Specific Example

Walk through a concrete instance where you used an AI tool (e.g., Copilot, ChatGPT, internal AI) to solve a problem, from initial challenge to resolution.

3. Explain Your Workflow

Detail how you integrate AI into your daily routine: for code generation, debugging, documentation, or learning new APIs, and how you verify its output.

4. Discuss Trade-offs and Limitations

Acknowledge scenarios where AI tools fall short (e.g., complex logic, security concerns) and how you mitigate those risks.

5. Connect to Impact

Summarize how AI usage has improved your productivity, code quality, or team collaboration, tying it back to Google's engineering culture.

Key Points to Mention

  • Specific AI tools you use (e.g., GitHub Copilot, ChatGPT, internal Google AI tools) and their primary use cases.
  • How you validate AI-generated code: unit tests, code reviews, static analysis, and manual inspection.
  • Examples of debugging with AI: using AI to interpret error logs, suggest fixes, or explain unfamiliar code.
  • Awareness of AI limitations: hallucinations, outdated knowledge, security vulnerabilities, and bias.
  • Impact on your workflow: time saved, faster onboarding, improved code quality, or reduced toil.
  • Collaboration aspect: how you share AI best practices with teammates or contribute to internal AI tooling.

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.

Q3

Solve a matrix traversal problem that requires backtracking to explore all valid paths or configurations.

Algorithms & Data Structures
Author's notes

This is where things fell apart.

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AI HintsAI Generated

Suggested Approach

Clarify the problem constraints and define the state space, then design a recursive backtracking solution that explores all valid paths while pruning invalid ones. Discuss time/space complexity and potential optimizations like memoization or iterative deepening if applicable.

Pro tip: Always discuss trade-offs between backtracking and other approaches (e.g., BFS/DFS, dynamic programming) and mention how you would handle large inputs or optimize for Google's scale.

1. Understand the problem

Ask clarifying questions to confirm the matrix dimensions, movement rules, constraints, and what constitutes a valid path or configuration.

2. Define state and choices

Identify the state representation (e.g., current position, visited cells, path so far) and the possible moves from each state.

3. Design backtracking algorithm

Outline a recursive function that explores each choice, marks/unmarks visited cells, and collects valid solutions.

4. Analyze complexity and optimize

Discuss worst-case time and space complexity, and suggest pruning techniques or memoization to improve efficiency.

5. Test with examples

Walk through a small example to verify correctness, and consider edge cases like empty matrix or no valid paths.

Key Points to Mention

  • Base case and termination conditions for recursion
  • State management: marking visited cells and backtracking (unmarking)
  • Pruning invalid paths early to reduce search space
  • Time complexity: O(4^(m*n)) worst-case for grid traversal, but often much less with constraints
  • Space complexity: O(m*n) for recursion stack and visited set
  • Potential optimizations: memoization, bidirectional search, or A* if applicable

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.

Q4

Online coding challenge: optimize a customer loyalty system (array-based problem) and solve the Largest Rectangle in Histogram.

Algorithms & Data Structures
Author's notes

The histogram one I'd actually practiced so that felt good.

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AI HintsAI Generated

Suggested Approach

For the loyalty system optimization, clarify the problem constraints and identify whether the array represents points, transactions, or customer segments, then apply appropriate techniques like prefix sums, sliding window, or sorting. For Largest Rectangle in Histogram, explain the monotonic stack approach, emphasizing how it efficiently finds the nearest smaller elements to compute maximal rectangles in O(n) time.

Pro tip: Always discuss trade-offs between different solutions (e.g., brute force vs. optimized) and mention edge cases like empty input or duplicate values, as Google values thorough analysis and robustness.

1. Clarify the problem

Ask clarifying questions to understand input format, constraints, and expected output for both problems. Confirm assumptions before diving into solutions.

2. Outline a brute-force approach

Briefly describe a naive solution and its time/space complexity to establish a baseline. This shows you can think simply before optimizing.

3. Optimize with appropriate data structures

For the loyalty system, consider prefix sums, sliding window, or sorting based on the problem. For histogram, use a monotonic stack to achieve O(n) time.

4. Walk through an example

Trace your algorithm on a small example to verify correctness and explain how it handles edge cases. This demonstrates clear communication.

5. Analyze complexity and trade-offs

State the time and space complexity of your solution and compare with alternatives. Discuss any assumptions or limitations.

Key Points to Mention

  • Time and space complexity analysis for each solution
  • Use of monotonic stack for Largest Rectangle in Histogram
  • Handling edge cases such as empty array, single element, or all equal heights
  • Trade-offs between different approaches (e.g., sorting vs. hashing for loyalty system)
  • Clear variable naming and modular code structure
  • Testing with provided examples and additional custom cases

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.