Immuta India SDET Interview: Rounds, Questions and Preparation

What the job involves

As an SDET at a fast-growing global tech company, you will design and build automated test suites, write code to validate APIs and UIs, and integrate tests into CI/CD pipelines. You will work closely with developers and product managers to catch issues early and improve release quality. The role blends software engineering with testing, so you will spend more time coding test frameworks than manually executing test cases.

Role and Technical Knowledge

1. 1

   What is the difference between a QA Engineer and an SDET?

   A strong answer highlights that SDETs write production-level automation code, build test frameworks, and contribute to CI/CD, while QAs may focus more on manual testing and process.

2. 2

   How do you decide what to automate versus what to test manually?

   Mention factors like frequency of execution, stability of the feature, cost of automation, and risk. Give an example like automating regression suites but manually testing exploratory or usability scenarios.

3. 3

   Explain the test pyramid and how it applies to a modern microservices application.

   Cover unit tests at the base, integration or API tests in the middle, and UI tests at the top. Explain that for microservices, API and contract tests are critical and UI tests should be minimal.

4. 4

   What is a flaky test and how would you handle it in a CI pipeline?

   Define flaky tests as those with inconsistent results. Discuss root causes like timing, environment, or test data issues, and solutions like retries, better waits, isolation, and quarantining.

Automation and Coding

1. 5

   Write a Java or Python program to find the second largest number in an array without sorting.

   A strong answer uses a single pass with two variables, handles edge cases like duplicates and arrays with fewer than two elements, and explains time complexity.

2. 6

   How do you handle dynamic web elements in Selenium?

   Mention using relative XPath, CSS selectors, explicit waits, and avoiding brittle locators. Give an example of a dynamic ID and how you would locate it by partial attribute or text.

3. 7

   What is the Page Object Model and why is it useful?

   Explain that POM separates page structure from test logic, improves readability, and reduces duplication. Mention how you would implement it with classes for each page and methods for actions.

4. 8

   How would you test a REST API endpoint that returns a list of users with pagination?

   Cover status codes, response schema, pagination parameters, edge cases like empty pages or invalid page numbers, and using Rest Assured or Postman with assertions.

Practical Scenarios

1. 9

   You join a team with no automated tests. How would you start building an automation framework from scratch?

   Outline steps: choose language and tools based on team skills, set up version control, create a simple smoke test, integrate with CI, and gradually expand coverage. Emphasize starting small and getting feedback.

2. 10

   A critical bug is found in production right before a release. How do you handle it?

   Discuss triaging severity, communicating with stakeholders, writing a regression test to reproduce, fixing and verifying, and adding a post-mortem to prevent similar issues.

3. 11

   How would you test a feature that depends on a third-party payment gateway?

   Mention using mocks or sandbox environments, testing success and failure scenarios, validating webhooks, and ensuring idempotency. Highlight not hitting real payment systems in automated tests.

4. 12

   Your automated test suite takes 2 hours to run. How would you reduce the feedback time?

   Suggest parallel execution, splitting into smoke and regression suites, running only affected tests on pull requests, and optimizing slow tests. Mention tools like Selenium Grid or TestNG parallel.

Behavioural and HR

1. 13

   Tell me about a time you found a bug that others missed. How did you handle it?

   Use STAR format. Focus on your attention to detail, how you reproduced and reported the bug clearly, and the impact of fixing it before release.

2. 14

   Why do you want to work as an SDET at a fast-growing company rather than a large established firm?

   Show enthusiasm for wearing multiple hats, learning quickly, and having a direct impact. Mention adaptability and interest in building processes from early stages.

3. 15

   Describe a situation where you had to learn a new tool or technology quickly for a project.

   Give a specific example, such as learning Selenium or Rest Assured for a college project or internship. Highlight your learning approach and how you applied it successfully.

4. 16

   How do you handle disagreements with a developer who says your bug is not reproducible?

   Emphasize clear communication, providing detailed steps, logs, and screenshots, and collaborating to reproduce together. Show that you focus on solving the issue, not blaming.