Sr. Software Test Engineer

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., + 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.

Experience working with precision equipment, preferably in photonics industry *

• 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., + 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.

parental leave, paid holidays, sick time, tuition reimbursement, 401(k), 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 acriminalhistory pursuant to the California Fair Chance Act and the Los Angeles County Fair Chance Ordinance for Employers.

Globally, our policy is to recruit individuals from wide and diverse backgrounds. However, certain positions require access to controlled goods and technologies subject to the International Traffic in Arms Regulations (ITAR) or Export Administration Regulations (EAR). Applicants for these positions may need to be “U.S. persons.” “U.S. persons” are generally defined as U.S. citizens, noncitizen nationals, lawful permanent residents (or, green card holders), individuals granted asylum, and individuals admitted as refugees.