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Sam's Club·Software Engineer·Onsite - Multi Round·Senior

SeniorOffer
Mar 2025Remote

Summary

Went through the full Sam's Club SDE loop: online assessment, a coding round, system design, and behavioral. Took a few months of cold applying before a recruiter bit, and there was actually a mid-process pivot where the original role rejected me but a different team picked me up for the final round. Ended with an offer.

Questions Asked (5)

Q1

Given a list of products with custom attributes, filter and return only the products that match a specified criteria.

Algorithms & Data StructuresAdaptability & Ambiguity
Author's notes

The prompt was deliberately vague, which I didn't fully appreciate at first.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the criteria and data structure, then discuss a general filtering approach. Implement a solution that iterates through products and checks each against the criteria, considering efficiency and edge cases.

Pro tip: Demonstrate adaptability by acknowledging ambiguous requirements and proposing a flexible solution that can easily accommodate changes, such as using a predicate function or strategy pattern.

1. Clarify Requirements

Ask questions to understand the criteria format, product attributes, and expected output. Confirm if the filtering should be inclusive or exclusive, and if multiple criteria can be combined.

2. Choose Data Structures

Decide on appropriate data structures for products and criteria. Consider using a list for products and a dictionary or object for attributes, and a function or lambda for the criteria.

3. Design Algorithm

Outline a simple iteration approach: loop through each product, check if it matches the criteria, and collect matches. Discuss time complexity and potential optimizations like indexing if needed.

4. Handle Edge Cases

Consider empty product list, missing attributes, invalid criteria, and performance for large datasets. Mention how to handle these gracefully.

5. Implement and Test

Write clean code with meaningful variable names, and walk through a test case to verify correctness. Mention unit testing or edge case testing.

Key Points to Mention

  • Time and space complexity of the filtering algorithm
  • Use of higher-order functions like filter or list comprehensions
  • Handling missing or null attributes in products
  • Extensibility for multiple criteria or complex conditions
  • Performance considerations for large datasets (e.g., indexing, lazy evaluation)
  • Clear communication of assumptions and trade-offs

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

Q2

Solve a custom variation of the classic balanced parentheses problem.

Algorithms & Data Structures
Author's notes

Pretty straightforward, nothing that'll keep you up at night.

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AI HintsAI Generated

Suggested Approach

First, clarify the custom variation by asking targeted questions about the rules, input format, and edge cases. Then, outline a stack-based solution, explaining how to adapt the classic algorithm to handle the new constraints, and analyze time and space complexity.

Pro tip: Demonstrate maturity by discussing potential ambiguities and proposing test cases before coding. This shows you think like a senior engineer who values correctness and collaboration.

1. Clarify the Problem

Ask questions to understand the custom variation: What characters are considered parentheses? Are there multiple types? What are the matching rules? What should the function return?

2. Outline the Approach

Explain that you'll use a stack to track opening brackets. For each character, if it's an opening bracket, push it; if it's a closing bracket, check if it matches the top of the stack.

3. Handle Custom Rules

Describe how to modify the classic algorithm for the custom variation, such as supporting wildcards, multiple bracket types, or additional constraints like maximum depth.

4. Analyze Complexity

State that the time complexity is O(n) and space complexity is O(n) in the worst case, but may be optimized to O(1) if only one type of bracket and no wildcards.

5. Test with Examples

Walk through a few test cases, including edge cases like empty string, single bracket, and nested brackets, to verify the solution.

Key Points to Mention

  • Stack data structure for matching brackets
  • Time and space complexity analysis
  • Handling edge cases (empty string, unbalanced brackets)
  • Adapting to custom rules (e.g., wildcards, multiple types)
  • Potential optimizations (e.g., using a counter for single type)
  • Clear communication and clarifying questions

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

Q3

Design a mobile notification system where users subscribe to retailers and receive push alerts when those retailers run special events like sales.

System DesignTechnical Trade-offs
Author's notes

I fumbled this one.

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AI HintsAI Generated

Suggested Approach

Start by clarifying functional and non-functional requirements, such as scale, latency, and delivery guarantees. Then design a high-level architecture covering subscription management, event ingestion, and push notification delivery, diving into trade-offs for each component. Finally, discuss how to handle failures, scale, and ensure reliability.

Pro tip: Emphasize the importance of idempotency and deduplication in notification delivery to avoid spamming users, and discuss how to handle retailer events that may trigger a large fan-out.

1. Clarify Requirements

Ask questions to understand scale (number of users, retailers, events per day), latency requirements, delivery guarantees (at-least-once, exactly-once), and user preferences (e.g., opt-out, frequency capping).

2. High-Level Design

Outline the main components: a subscription service (managing user-retailer relationships), an event ingestion pipeline (receiving retailer events), a matching engine (identifying interested users), and a notification delivery service (sending push notifications via APNs/FCM).

3. Deep Dive into Components

Detail each component: how subscriptions are stored (e.g., database schema), how events are processed (e.g., message queue, stream processing), how matching scales (e.g., fan-out on write vs. read), and how notifications are sent reliably (e.g., retries, dead-letter queues).

4. Address Trade-offs and Scalability

Discuss trade-offs such as push vs. pull for event delivery, synchronous vs. asynchronous processing, and how to scale each part (e.g., sharding, partitioning). Mention consistency vs. availability for subscription data.

5. Handle Failures and Edge Cases

Explain how to handle failures (e.g., retries, idempotency, deduplication), ensure delivery guarantees, and manage edge cases like user unsubscribes, retailer event bursts, and notification fatigue.

Key Points to Mention

  • Use of message queues (e.g., Kafka) for decoupling event ingestion and notification delivery, enabling scalability and fault tolerance.
  • Fan-out strategies: fan-out on write (precompute user notifications) vs. fan-out on read (compute at delivery time) and their trade-offs.
  • Idempotency and deduplication to prevent duplicate notifications, especially with at-least-once delivery.
  • Rate limiting and frequency capping to avoid overwhelming users and comply with push notification policies.
  • Integration with third-party push services (APNs, FCM) and handling their rate limits and failures.
  • Data storage choices: NoSQL for subscriptions (e.g., Cassandra) vs. relational, and indexing for efficient matching.

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

Q4

Frontend debugging task: identify and fix issues in a provided React codebase.

Technical Trade-offs
Author's notes

This was part of the online assessment and the one area where I didn't get full marks.

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AI HintsAI Generated

Suggested Approach

Start by reproducing the bug and understanding the expected behavior, then systematically inspect the code for common React pitfalls like state mutation, missing keys, or incorrect dependency arrays. Fix the issues one at a time, verifying each change with tests or manual checks, and explain your reasoning throughout.

Pro tip: Before diving into fixes, use React DevTools to inspect component props, state, and re-renders—this often reveals the root cause faster than reading code. Also, mention how you'd prevent similar bugs with linting rules or tests.

1. Reproduce and Understand

Run the app, reproduce the bug, and clarify the expected behavior. Check the console for errors or warnings.

2. Inspect and Hypothesize

Use React DevTools and code inspection to identify potential causes, such as state mutation, stale closures, or improper effect dependencies.

3. Fix and Verify

Apply a targeted fix, then verify it resolves the issue without breaking other functionality. Run tests or manually test related features.

4. Explain and Prevent

Explain the root cause and how the fix works. Suggest preventive measures like lint rules, tests, or code review practices.

Key Points to Mention

  • Common React anti-patterns: mutating state directly, missing keys in lists, incorrect useEffect dependencies
  • Using React DevTools to inspect component hierarchy, props, state, and re-renders
  • The importance of writing tests to catch regressions and verify fixes
  • Performance considerations: unnecessary re-renders, memoization, and profiling
  • Trade-offs between quick fixes and long-term maintainability
  • Communication: explaining your debugging process and reasoning clearly

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

Q5

Behavioral round: describe situations where you navigated challenges, led through difficulty, or drove outcomes on a team.

Adaptability & AmbiguityCross-functional Alignment
Author's notes

Standard stuff.

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AI HintsAI Generated

Suggested Approach

Use the STAR method to structure your answer, focusing on a specific situation where you faced a challenge, ambiguity, or cross-functional misalignment. Highlight your actions as a software engineer to drive alignment and outcomes, and quantify the results to show impact. Choose a story that demonstrates both adaptability and collaboration.

Pro tip: Emphasize how you turned ambiguity into clarity by asking questions, proposing solutions, and aligning stakeholders—this shows leadership without authority, which is highly valued at Sam's Club.

1. Set the Context

Briefly describe the project, team, and the challenge or ambiguity you faced. Keep it concise to focus on your actions.

2. Explain the Challenge

Detail the specific difficulty: unclear requirements, conflicting priorities, technical hurdles, or cross-team dependencies. Highlight why it was challenging.

3. Describe Your Actions

Explain the steps you took to navigate the challenge, such as facilitating discussions, prototyping, or aligning stakeholders. Focus on your specific contributions.

4. Share the Outcome

Quantify the results: improved efficiency, reduced bugs, faster delivery, or better team alignment. Mention any lessons learned.

5. Connect to Sam's Club

Relate the experience to Sam's Club's values, such as member focus, teamwork, or innovation, to show cultural fit.

Key Points to Mention

  • Navigating ambiguity by breaking down problems and seeking clarification
  • Leading through influence without formal authority
  • Cross-functional collaboration and alignment with product, design, or business teams
  • Technical decision-making and trade-offs
  • Measurable outcomes (e.g., reduced time-to-market, improved system reliability)
  • Adaptability to changing requirements or priorities

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