Sr. Software Test Engineer

MKS Instruments•Milpitas, CA

2d•$110,000 - $155,000

About The Position

As a Sr. Software Test Engineer in the Lasers Business Unit at MKS Instruments, you will partner with Spectra-Physics scientists and engineers across software, electrical, and systems disciplines to help ensure software and system quality for new free-space and fiber-based laser systems. You will develop and execute test strategies and report to the Sr. Manager, Software Engineering. The role covers test planning and execution for embedded firmware, GUI validation, performance and compatibility testing across embedded platforms and hardware, defect identification and resolution, test automation, requirements traceability, risk management, and troubleshooting customer- and field-reported issues. Work takes place in a lab or office setting, with prolonged sitting. The position offers a salary range of $110,000 to $155,000 per year and eligibility for a discretionary annual bonus. MKS lists a benefits package that includes health insurance, a 401(k) with company match, life and disability insurance, paid holidays, sick time, paid vacation, paid parental leave, adoption assistance, and tuition reimbursement.

Requirements

Bachelor of Science degree in Software Engineering, Computer Engineering, Electrical Engineering, or equivalent.
At least 5 years of related software QA experience with embedded systems and GUIs.
Demonstrable proficiency programming in C/C# and Python.
Experience with testing frameworks such as Unity, Pytest, GTest, NUnit, or xUnit.
Familiarity with CI/CD tools, version control, and bug-tracking systems such as JIRA.
Familiarity with interfaces including I2C, SPI, RS-232, RS-485, Ethernet, and USB.
Experience with test equipment such as DVMs, power supplies, and oscilloscopes.
Excellent communication, documentation, and organizational skills.
Ability to sit for prolonged periods in a lab or office setting.

Nice To Haves

Experience working with precision equipment, preferably in the photonics industry.
Exposure to DevSecOps and cybersecurity principles.
Experience using LLMs or other AI tools for test case generation, test data creation, and defect analysis.
Ability to read electronic schematic diagrams and component datasheets.
Experience with real-time operating systems such as Azure/ThreadX or FreeRTOS, and/or Linux.
Experience working with distributed teams.

Responsibilities

Develop, maintain, and execute structured manual and automated test plans and cases for embedded firmware at feature, integration, and system levels.
Validate GUIs for usability, functionality, responsiveness, and compatibility with target hardware and operating systems.
Test software performance on embedded platforms and integration with hardware, firmware, and photonics modules.
Document defects, trace them to requirements, and work with developers to resolve issues.
Use automated testing tools for regression, functional, and GUI testing to improve test speed and coverage.
Maintain traceability matrices linking requirements to test cases and results.
Identify failure modes early to prevent costly late-stage fixes.
Reproduce, troubleshoot, and thoroughly test field-reported and customer-facing bugs in live or simulated environments.