Sr. Software Test Engineer

MKS Inc.; Milpitas (CA); On-site; USD 110,000 - 155,000; Full time

Benefits offered by this job

Health insurance (medical, dental, etc

401(k) with company match

Life and disability insurance

12 paid holidays

15 paid vacation days

6 weeks fully paid parental leave

Tuition reimbursement

Job summary

MKS Instruments in Milpitas, CA, seeks a Sr. Software Test Engineer to ensure software and system quality for laser systems. You will develop test strategies, plan and execute tests, and collaborate with Spectra-Physics teams to deliver robust embedded solutions.

You will work on GUI testing, automation, traceability, and risk management, reporting to the Sr. Manager of Software Engineering in the Lasers Business Unit.

Qualifications

• BS degree in a relevant engineering field.
• 5+ years of QA for embedded systems and GUIs.
• Proficiency in C/C# and Python.
• Experience with testing frameworks and CI/CD tooling.

Responsibilities

• Develop, maintain, and execute test plans and cases for embedded firmware (manual and automated).
• GUI testing for usability, functionality, and compatibility with hardware and OS.
• Performance and compatibility testing for embedded platforms.
• Document defects, trace to requirements, and drive fixes with devs.
• Use automated testing to improve regression coverage and speed.
• Maintain traceability matrices linking requirements to tests.
• Identify failure modes early to prevent late-stage fixes.
• Troubleshoot field-reported and customer bugs in live or simulated environments.

Skills

5+ years QA experience

C/C# and Python

GUI testing

DevSecOps awareness

Communication & documentation

Education

BS degree in Software Engineering, Computer Engineering, Electrical Engineering, or equivalent

Tools

Unity

Pytest

GTest

NUnit

xUnit

JIRA

CI/CD tools

Version control

I2C, SPI, RS-232, RS-485, Ethernet, USB

Test equipment (DVM, Power Supply, Oscilloscopes)

Job description

A Day in Your Life at MKS

As a Sr. Software Test Engineer at the Lasers Business Unit of MKS Instruments, you will partner with Spectra-Physics Scientists and Engineers; Software, Electrical and System to contribute to ensure the software and system quality for the new free-space and fiber-based laser systems by developing and executing test strategy. In this role, you will report to the Sr. Manager, Software Engineering.

You Will Make an Impact By

• Test Planning & Execution: Develop, maintain, and execute well-structured test plans and test cases (manual and automated) for embedded firmware, covering features, integration, and system levels.
• GUI Testing: Validate GUIs for usability, functionality, responsiveness, and compatibility with target hardware and operating systems.
• Performance & Compatibility Testing: Ensure software runs efficiently on embedded platforms and integrates well with hardware, firmware, and photonics modules.
• Bug Identification & Resolution: Document defects, trace them back to requirements, and work with developers to fix issues.
• Automation: Use automated testing tools for regression testing, functional testing, and GUI validation to improve speed and coverage.
• Traceability: Maintain traceability matrices linking requirements to test cases and results.
• Risk Management: Identify failure modes early to prevent costly late-stage fixes.
• Troubleshooting: Reproduce, troubleshoot, and thoroughly test field-reported and customer-facing bugs in live or simulated environments

Skills You Bring

• BS degree in Software Engineering, Computer Engineering, Electrical Engineering, or equivalent.
• 5+ years related Software QA experience with embedded systems and GUIs.
• Exposure to DevSecOps and cyber security principles is desired.
• Demonstrable proficiency programming in C/C# and Python.
• Experience with testing frameworks like Unity, Pytest, GTest, NUnit, xUnit.
• Well versed in CI/CD tools, version control, and bug tracking system like JIRA.
• Familiarity with interfaces such as I2C, SPI, RS-232, RS-485, Ethernet & USB.
• Experience with test equipment (DVM, Power Supply, Oscilloscopes).
• Excellent communication, documentation & organizational skills.

Preferred Skills

• Experience using LLMs or other AI tools for tasks like test case generation, test data creation, and defect analysis is a plus.
• Ability to read electronic schematic diagrams & component datasheets.
• Experience with Real-Time Operating Systems (Azure/Threadx, FreeRTOS), and/or Linux.
• Experience working with distributed teams.

Physical Demands and Working Conditions

• Sitting for prolonged periods of time in a lab or office setting

Compensation and Benefits

• Salary Pay Range: $110,000.00 - 155,000.00 per year. This range is a good faith estimate of the expected salary range for this position, based on a wide range of factors including qualifications, experience and training, operational and business needs and other considerations permitted by law.
• Bonus: This position is eligible for a discretionary annual bonus, in an amount to be determined by MKS [or as applicable].
• Benefits: MKS offers a comprehensive benefits package, including health insurance coverage (medical, dental and vision), 401(k) with company match, life and disability insurance, 12 paid holidays, sick time, 15 paid vacation days, [6 weeks fully paid] parental leave, adoption assistance and tuition reimbursement [and for participation in any stock programs, signing bonus, etc.

MKS is an equal opportunity employer, including disability, veteran status and all categories protected by law. Please review our EOE statements for additional details. MKS is generally only hiring candidates who reside in states where we are registered to do business.

MKS will consider qualified applicants with a criminal history pursuant to the California Fair Chance Act and the Los Angeles County Fair Chance Ordinance for Employers.