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Guardant Health Interview Questions

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Let’s say that your company is running a standard control and variant AB test on a feature to increase conversion rates on the landing page. The PM checks the results and finds a .04 p-value.

How would you assess the validity of the result?

Experiment Validity

You are testing hundreds of hypotheses with many t-tests. What considerations should be made?

What is a key disadvantage of the F-test when compared to multiple t-tests?

What is a key disadvantage of the F-test when compared to multiple t-tests?

Hundreds of Hypotheses

You are testing hundreds of hypotheses with many t-tests. What considerations should be made?

Let’s say we have a table with an <code>id</code> and <code>name</code> fields. The table holds over 100 million rows and we want to sample a random row in the table without throttling the database.

Write a query to randomly sample a row from this table.

Input:

<code>big_table</code> table

<table>
<thead>
<tr>
<th>Columns</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>id</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>name</code></td>
<td>VARCHAR</td>
</tr>
</tbody>
</table>

Write a query to randomly sample a row from a big table.

Random SQL Sample

Guardant Health Salaries by Position

Company Description Guardant Health is a leading precision oncology company focused on helping conquer cancer globally through use of its proprietary tests, vast data sets and advanced analytics. The Guardant Health oncology platform leverages capabilities to drive commercial adoption, improve patient clinical outcomes and lower healthcare costs across all stages of the cancer care continuum. Guardant Health has commercially launched Guardant360, Guardant360 CDx, Guardant360 TissueNext, Guardant360 Response, and GuardantOMNI tests for advanced stage cancer patients, and Guardant Reveal for early-stage cancer patients. The Guardant Health screening portfolio, including the Shield test, aims to address the needs of individuals eligible for cancer screening. Job Description About the Role: We are seeking an experienced and innovative Staff Software Engineer, Test Automation to lead the design, development, and implementation of robust automated testing frameworks for our software products. This role requires a strategic thinker with hands-on experience in building scalable test automation architectures and a deep understanding of software quality assurance practices. As a key contributor to our development team, you will shape our automation strategy, establish best practices, and collaborate with cross-functional teams to deliver high-quality software solutions. Essential Duties and Responsibilities: Architect and Implement Automation Frameworks: Design and develop scalable, maintainable, and effective test automation frameworks from scratch or enhance existing ones to support comprehensive testing strategies. Automation Strategy Development: Define, implement, and continuously improve the automation testing strategy aligned with project and company goals, ensuring efficiency and scalability. Technology Leadership: Research, evaluate, and implement cutting-edge tools and technologies in test automation, CI/CD integration, and quality assurance. Collaborate Across Teams: Work closely with development, QA, DevOps, and product management teams to integrate automated testing into the software development lifecycle and ensure quality checkpoints throughout. Mentorship and Training: Mentor and train QA engineers and software developers on test automation best practices, tool usage, and framework architecture. Code Reviews and Quality Checks: Conduct code reviews of automated test scripts to ensure adherence to best practices, reusability, and maintainability. Monitoring and Reporting: Establish automated reporting tools and dashboards for tracking testing progress and metrics to provide insights on code quality and release readiness. Continuous Improvement: Champion a culture of quality and continuous improvement, identifying areas for process optimization and workflow enhancements. Qualifications Education: Bachelor's or Master's degree in Computer Science, Engineering, or a related field. Experience: 7 years of experience in software quality assurance, with at least 3 years focused on test automation and framework development. Technical Skills: Strong programming skills in one or more languages such as Java, Python, C#, or JavaScript. Expertise in test automation tools and frameworks (e.g., Selenium, Appium, Cypress, TestNG, JUnit). Familiarity with CI/CD tools like Jenkins, GitLab CI, or Azure DevOps. Experience with cloud-based test automation solutions (e.g., AWS Device Farm, Sauce Labs, BrowserStack) is a plus. Strong knowledge of software testing methodologies, including unit, functional, integration, and performance testing. Analytical Skills: Strong problem-solving skills with a deep understanding of software architecture and design principles. Communication Skills: Excellent verbal and written communication skills, with the ability to collaborate effectively with technical and non-technical stakeholders. Leadership and Mentorship: Proven ability to lead, mentor, and guide QA teams and developers in test automation practices and tools. Preferred Qualifications: Certifications: ISTQB Certification or similar is a plus. Agile Experience: Experience working in Agile/Scrum environments. Industry Experience: Experience in biotech or similar. Additional Information Hybrid Work Model : At Guardant Health, we have defined days for in-person/onsite collaboration and work-from-home days for individual-focused time. All U.S. employees who live within 50 miles of a Guardant facility will be required to be onsite on Mondays, Tuesdays, and Thursdays. We have found aligning our scheduled in-office days allows our teams to do the best work and creates the focused thinking time our innovative work requires. At Guardant, our work model has created flexibility for better work-life balance while keeping teams connected to advance our science for our patients. The US base salary range for this full-time position is $130,800 to $209,300. The range does not include benefits, and if applicable, bonus, commission, or equity. The range displayed reflects the minimum and maximum target for new hire salaries across all US locations for the posted role with the exception of any locations specifically referenced below (if any). For positions based in Palo Alto, CA or Redwood City, CA, the base salary range for this full-time position is $174,400 to $235,400. The range does not include benefits, and if applicable, bonus, commission, or equity. Within the range, individual pay is determined by work location and additional factors, including, but not limited to, job-related skills, experience, and relevant education or training. If you are selected to move forward, the recruiting team will provide details specific to the factors above. Employee may be required to lift routine office supplies and use office equipment. Majority of the work is performed in a desk/office environment; however, there may be exposure to high noise levels, fumes, and biohazard material in the laboratory environment. Ability to sit for extended periods of time. Guardant Health is committed to providing reasonable accommodations in our hiring processes for candidates with disabilities, long-term conditions, mental health conditions, or sincerely held religious beliefs. If you need support, please reach out to Peopleteamguardanthealth.com Guardant Health is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, or protected veteran status and will not be discriminated against on the basis of disability. All your information will be kept confidential according to EEO guidelines. To learn more about the information collected when you apply for a position at Guardant Health, Inc. and how it is used, please review our Privacy Notice for Job Applicants . Please visit our career page at: http://www.guardanthealth.com/jobs/ LI-CS4

<h3>Job Description</h3><div>Job Description<div>Company Description Guardant Health is a leading precision oncology company focused on helping conquer cancer globally through use of its proprietary tests, vast data sets and advanced analytics. The Guardant Health oncology platform leverages capabilities to drive commercial adoption, improve patient clinical outcomes and lower healthcare costs across all stages of the cancer care continuum. Guardant Health has commercially launched Guardant360®, Guardant360 CDx, Guardant360 TissueNext™, Guardant360 Response™, and GuardantOMNI® tests for advanced stage cancer patients, and Guardant Reveal™ for early-stage cancer patients. The Guardant Health screening portfolio, including the Shield™ test, aims to address the needs of individuals eligible for cancer screening.Job Description About the Role:We are seeking an experienced and innovative Staff Software Engineer, Test Automation to lead the design, development, and implementation of robust automated testing frameworks for our software products. This role requires a strategic thinker with hands-on experience in building scalable test automation architectures and a deep understanding of software quality assurance practices. As a key contributor to our development team, you will shape our automation strategy, establish best practices, and collaborate with cross-functional teams to deliver high-quality software solutions.Essential Duties and Responsibilities:<ul><li>Architect and Implement Automation Frameworks: Design and develop scalable, maintainable, and effective test automation frameworks from scratch or enhance existing ones to support comprehensive testing strategies.</li><li>Automation Strategy Development: Define, implement, and continuously improve the automation testing strategy aligned with project and company goals, ensuring efficiency and scalability.</li><li>Technology Leadership: Research, evaluate, and implement cutting-edge tools and technologies in test automation, CI/CD integration, and quality assurance.</li><li>Collaborate Across Teams: Work closely with development, QA, DevOps, and product management teams to integrate automated testing into the software development lifecycle and ensure quality checkpoints throughout.</li><li>Mentorship and Training: Mentor and train QA engineers and software developers on test automation best practices, tool usage, and framework architecture.</li><li>Code Reviews and Quality Checks: Conduct code reviews of automated test scripts to ensure adherence to best practices, reusability, and maintainability.</li><li>Monitoring and Reporting: Establish automated reporting tools and dashboards for tracking testing progress and metrics to provide insights on code quality and release readiness.</li><li>Continuous Improvement: Champion a culture of quality and continuous improvement, identifying areas for process optimization and workflow enhancements.</li></ul>Qualifications <ul><li>Education: Bachelor’s or Master’s degree in Computer Science, Engineering, or a related field.</li><li>Experience: 7+ years of experience in software quality assurance, with at least 3 years focused on test automation and framework development.</li></ul>Technical Skills:<ul><li>Strong programming skills in one or more languages such as Java, Python, C#, or JavaScript.</li><li>Expertise in test automation tools and frameworks (e.g., Selenium, Appium, Cypress, TestNG, JUnit).</li><li>Familiarity with CI/CD tools like Jenkins, GitLab CI, or Azure DevOps.</li><li>Experience with cloud-based test automation solutions (e.g., AWS Device Farm, Sauce Labs, BrowserStack) is a plus.</li><li>Strong knowledge of software testing methodologies, including unit, functional, integration, and performance testing.</li><li>Analytical Skills: Strong problem-solving skills with a deep understanding of software architecture and design principles.</li><li>Communication Skills: Excellent verbal and written communication skills, with the ability to collaborate effectively with technical and non-technical stakeholders.</li><li>Leadership and Mentorship: Proven ability to lead, mentor, and guide QA teams and developers in test automation practices and tools.</li></ul>Preferred Qualifications:<ul><li>Certifications: ISTQB Certification or similar is a plus.</li><li>Agile Experience: Experience working in Agile/Scrum environments.</li><li>Industry Experience: Experience in biotech or similar.</li></ul> Additional Information Hybrid Work Model: At Guardant Health, we have defined days for in-person/onsite collaboration and work-from-home days for individual-focused time. All U.S. employees who live within 50 miles of a Guardant facility will be required to be onsite on Mondays, Tuesdays, and Thursdays. We have found aligning our scheduled in-office days allows our teams to do the best work and creates the focused thinking time our innovative work requires. At Guardant, our work model has created flexibility for better work-life balance while keeping teams connected to advance our science for our patients.The US base salary range for this full-time position is $130,800 to $209,300. The range does not include benefits, and if applicable, bonus, commission, or equity. The range displayed reflects the minimum and maximum target for new hire salaries across all US locations for the posted role with the exception of any locations specifically referenced below (if any).For positions based in Palo Alto, CA or Redwood City, CA, the base salary range for this full-time position is $174,400 to $235,400. The range does not include benefits, and if applicable, bonus, commission, or equity.Within the range, individual pay is determined by work location and additional factors, including, but not limited to, job-related skills, experience, and relevant education or training. If you are selected to move forward, the recruiting team will provide details specific to the factors above.Employee may be required to lift routine office supplies and use office equipment. Majority of the work is performed in a desk/office environment; however, there may be exposure to high noise levels, fumes, and biohazard material in the laboratory environment. Ability to sit for extended periods of time.Guardant Health is committed to providing reasonable accommodations in our hiring processes for candidates with disabilities, long-term conditions, mental health conditions, or sincerely held religious beliefs. If you need support, please reach out to Peopleteam@guardanthealth.comGuardant Health is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, or protected veteran status and will not be discriminated against on the basis of disability.All your information will be kept confidential according to EEO guidelines. To learn more about the information collected when you apply for a position at Guardant Health, Inc. and how it is used, please review our Privacy Notice for Job Applicants.Please visit our career page at: http://www.guardanthealth.com/jobs/#LI-CS4</div></div>

<h3>Job Description</h3><div>Job Description<div>Company Description Guardant Health is a leading precision oncology company focused on helping conquer cancer globally through use of its proprietary tests, vast data sets and advanced analytics. The Guardant Health oncology platform leverages capabilities to drive commercial adoption, improve patient clinical outcomes and lower healthcare costs across all stages of the cancer care continuum. Guardant Health has commercially launched Guardant360®, Guardant360 CDx, Guardant360 TissueNext™, Guardant360 Response™, and GuardantOMNI® tests for advanced stage cancer patients, and Guardant Reveal™ for early-stage cancer patients. The Guardant Health screening portfolio, including the Shield™ test, aims to address the needs of individuals eligible for cancer screening.Job Description Guardant Health seeks an energetic and passionate Senior Software Quality Engineer to join its Software Engineering team. This team is responsible for delivering the product functionality needed to support the laboratory workflow for several of its market leading cancer diagnostic tests as well as integration with various oncology systems.An ideal candidate would have experience working in a regulated environment with a thorough knowledge of quality engineering best practices and technical expertise to deliver software products that meet business needs in an efficient and fast-paced environment. This role requires someone adept at understanding system architecture, design, and implementation to succinctly develop tailored test strategies and deliver quality software products meeting regulatory standards. The candidate should be apt to work on parallel projects with overlapping schedules, quickly learn new technologies, and demonstrate teamwork and technical leadership.Essential Duties and Responsibilities:<ul><li>Design and execute test coverage for various functional and integration aspects of the Enterprise Lab Information Management System (LabVantage).</li><li>Apply appropriate test methodologies, including but not limited to writing test plans and test cases and executing test scripts within the sprint schedule.</li><li>Create automated test cases and execute them to support scheduled releases.</li><li>Troubleshoot issues identified during testing and report defects; able to distinguish between user error and application anomalies.</li><li>Perform System Integration and performance testing before product releases.</li><li>Provide clear and concise feedback on defects, usability, and other test findings/results.</li><li>Contribute to the continuous improvement of QA processes and methodologies.</li><li>Collaborate with cross-functional teams to ensure timely and robust testing execution as part of a regular release schedule.</li><li>Provide coaching to other team members for designing test strategies and test cases.</li><li>Execute complex testing scenarios, perform in-depth statistical analysis, and interpret results independently.</li><li>Apply QE standards, best practices, and principles to develop quality plans that deliver optimal outcomes across multiple products.</li><li>Deliver test documentation to support software development for medical devices in compliance with FDA, IVDR, CE mark, IEC 62304, PMDA, and ISO 13485 standards.</li><li>Stay updated on industry best practices and emerging technologies relevant to software quality assurance in life sciences.</li></ul>Qualifications <ul><li>B.S. or higher degree in Computer Science, Engineering, Bioinformatics, or a related study or equivalent project experience.</li><li>8+ years of hands-on testing experience in Service Oriented Architecture environment using COTS/SaaS solutions with API led integrations.</li><li>Solid experience in programming languages like Java, Python</li><li>5+ years of experience in testing integrations in a hybrid environment leveraging XML/JSON/HL7 message formats.</li><li>5+ years of experience using databases like Postgres, Oracle, MSSQL Server or Mongo DB.</li><li>5+ years of experience in test preparation activities within an Agile Development Process – Test Design, Test scripting, Test Data creation.</li><li>5+ years of API test tools like Postman, Fiddler, RestAssured, SOAPUI, JMeter required.</li><li>Develop test automation scripts to support CI/CD pipeline for software delivery.</li><li>Proven ability to adapt to new technologies and design test strategies.</li><li>Extensive experience in good testing practices, QA methodologies, tools, and processes.</li><li>Excellent communication, presentation, and analytical skills, including strong ability to identify and solve ambiguous cross-functional software quality related problems.</li><li>Expertise in measuring and reporting quality-related metrics to identify trends, anomalies and proactively resolve problems.</li><li>Experience in identifying, analyzing, and narrowing down system integration issues and performing root cause analysis.</li><li>Expertise in developing and maintaining SDLC documentation such as Verification Plan, Report, Validation Plan, Risk Assessment, and Traceability Matrix, etc.</li><li>Ability to deliver software releases in frequent cycles using agile methodology.</li></ul> Desirable, but not Required:<ul><li>3+ years of performing verification and validation activities in medical device, pharma or healthcare regulated environments.</li><li>Experience working in a regulated environment (CLIA, CAP, HIPAA, SOX, 21 CFR Part 11, ISO 13485, IEC 62304, and other FDA regulations)</li><li>Working experience in MuleSoft platform.</li></ul> Additional Information Hybrid Work Model: At Guardant Health, we have defined days for in-person/onsite collaboration and work-from-home days for individual-focused time. All U.S. employees who live within 50 miles of a Guardant facility will be required to be onsite on Mondays, Tuesdays, and Thursdays. We have found aligning our scheduled in-office days allows our teams to do the best work and creates the focused thinking time our innovative work requires. At Guardant, our work model has created flexibility for better work-life balance while keeping teams connected to advance our science for our patients.For positions based in Palo Alto, CA or Redwood City, CA, the base salary range for this full-time position is $111,800 to $150,900 The range does not include benefits, and if applicable, bonus, commission, or equity.Within the range, individual pay is determined by work location and additional factors, including, but not limited to, job-related skills, experience, and relevant education or training. If you are selected to move forward, the recruiting team will provide details specific to the factors above.Employee may be required to lift routine office supplies and use office equipment. Majority of the work is performed in a desk/office environment; however, there may be exposure to high noise levels, fumes, and biohazard material in the laboratory environment. Ability to sit for extended periods of time.Guardant Health is committed to providing reasonable accommodations in our hiring processes for candidates with disabilities, long-term conditions, mental health conditions, or sincerely held religious beliefs. If you need support, please reach out to Peopleteam@guardanthealth.comGuardant Health is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, or protected veteran status and will not be discriminated against on the basis of disability.All your information will be kept confidential according to EEO guidelines. To learn more about the information collected when you apply for a position at Guardant Health, Inc. and how it is used, please review our Privacy Notice for Job Applicants.Please visit our career page at: http://www.guardanthealth.com/jobs/#LI-JL1, #LI-HIRING, #LI-SOFTWAREENGINEER</div></div>

Guardant Health Interview Questions

Guardant Health Interview Guides

Guardant Health Interview Questions

Guardant Health Salaries by Position

Guardant Health Opening Jobs