Sr. Software Test Engineer

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

Benefits offered by this job

Health insurance

401(k) with company match

Life & disability insurance

Holidays (12)

Paid vacation (15 days)

Parental leave (6 weeks)

Adoption assistance

Tuition reimbursement

Job summary

MKS Instruments in Milpitas, CA is seeking a Sr. Software Test Engineer to ensure software and system quality for laser systems by developing and executing test strategies across embedded firmware, GUI, and integration with hardware.

You will work with Spectra-Physics scientists and engineers, report to the Sr. Manager, Software Engineering, and apply automation, traceability, and risk management to prevent issues in late stages.

Qualifications

• BS degree in Software or Electrical Engineering with related QA focus.
• 5+ years of Software QA experience with embedded systems and GUIs.
• Exposure to DevSecOps and cybersecurity principles is desirable.
• Proficiency in C/C# and Python programming.
• Experience with testing frameworks: Unity, Pytest, GTest, NUnit, xUnit.
• Familiarity with CI/CD tools, version control, and JIRA.
• Knowledge of interfaces: I2C, SPI, RS-232, RS-485, Ethernet, USB.
• Experience with test equipment (DVM, power supplies, oscilloscopes).
• Excellent written and verbal communication and organization skills.

Responsibilities

• Develop, maintain, and execute test plans and cases for embedded firmware (manual and automated).
• GUI testing for usability and compatibility with hardware and OS.
• Perform performance and compatibility testing on embedded platforms.
• Document defects and drive resolution with developers.
• Use automation for regression, functional, and GUI validation.
• Maintain traceability matrices linking requirements to tests and results.
• Identify risk and failure modes early to prevent late-stage fixes.
• Reproduce and troubleshoot field or customer bugs in live or simulated environments.

Skills

Test planning & execution

GUI testing

Automation

Bug identification & resolution

Traceability

Risk management

Troubleshooting

C/C#

Python

CI/CD

JIRA

Embedded systems

Communication

Education

BS degree in Software Engineering, Computer Engineering, Electrical Engineering

Tools

Unity

Pytest

GTest

NUnit

xUnit

JIRA

Git

I2C

SPI

RS-232

RS-485

Ethernet

USB

DVM

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:

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.

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].

• 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
• 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.

MKS Inc. and its affiliates and subsidiaries ("MKS") is an affirmative action and equal opportunity employer: diverse candidates are encouraged to apply. We win as a team and are committed to recruiting and hiring qualified applicants regardless of race, color, national origin, sex (including pregnancy and pregnancy-related conditions), religion, age, ancestry, physical or mental disability or handicap, marital status, membership in the uniformed services, veteran status, sexual orientation, gender identity or expression, genetic information, or any other category protected by applicable law. Hiring decisions are based on merit, qualifications and business needs. We conduct background checks and drug screens, in accordance with applicable law and company policies. MKS is generally only hiring candidates who reside in states where we are registered to do business.