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LSEG·Software Engineer·Technical Phone Screen·Senior

SeniorPending
May 2026Bangalore

Summary

Got recruited by LSEG for a senior data engineer position in Bangalore, cleared an OA and a debugging-focused code pair interview, and now there's a second code pair round coming up focused on TDD and clean code. Posting here because the email description left me more confused than prepared.

Questions Asked (1)

Q1

In a TDD-focused code pair interview, how would you approach writing unit tests and structuring your code for readability and maintainability?

Technical Trade-offsAPI & IntegrationsAlgorithms & Data Structures
Author's notes

This is basically what I'm trying to figure out before walking in.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the problem and defining the expected behavior through tests, then iteratively write minimal code to pass each test while refactoring for clarity. Emphasize the red-green-refactor cycle and how you structure code into small, focused functions with clear naming and separation of concerns.

Pro tip: During the pair interview, narrate your thought process and invite your partner to contribute; this demonstrates collaboration and that you value collective code ownership. Also, write tests that are readable and act as documentation, not just assertions.

1. Clarify requirements and scope

Ask questions to understand the problem, edge cases, and expected behavior. Discuss with your partner to align on the approach before writing any code.

2. Write a failing test (Red)

Start with the simplest test that captures a small piece of desired behavior. Ensure the test fails for the right reason and is readable.

3. Write minimal code to pass (Green)

Implement just enough code to make the test pass, without over-engineering. Focus on making it work first.

4. Refactor for readability and maintainability

Improve the code structure, remove duplication, and enhance naming while keeping tests green. Apply design principles like SOLID and DRY.

5. Repeat and integrate

Continue the cycle for new behaviors, ensuring tests remain fast and isolated. Discuss how you would integrate with existing systems and handle dependencies.

Key Points to Mention

  • Red-Green-Refactor cycle and its importance in TDD
  • Writing tests first to drive design and clarify requirements
  • Keeping tests small, focused, and independent
  • Using descriptive test names and arrange-act-assert structure
  • Refactoring continuously to improve code quality
  • Collaboration and communication during pair programming

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