Process Engineering Associate I/II, Oncology

A Rare Opportunity to Shape the Future of Genomics

Join a team of brilliant, passionate innovators determined to transform healthcare. At BillionToOne, we've built a category-defining, publicly traded company on Nasdaq where transparency fuels trust, collaboration drives breakthroughs, and every contribution moves the needle on our mission to make life-changing diagnostics accessible to all. We don't just aim for incremental improvements; we build products that are 10x better than anything that exists today.

Our scientists, engineers, sales executives, and visionaries are united by an unwavering commitment to changing the standard of care in prenatal and cancer diagnostics. This is where cutting-edge science meets human compassion, and every innovation you contribute helps remove the fear of the unknown from some of life's most critical medical moments.

If you're driven by purpose, energized by innovation, and ready to help shape the future of precision medicine at scale, this is where you belong.

We are looking for a Process Engineering Associate to join our growing superstar Process Engineering team in support of clinical patient testing in our high throughput CLIA lab. The PEA I is responsible for (1) developing new tools for improved clinical workflow efficiency, (2) analyzing process data to monitor and troubleshoot our high-throughput assays, 3) identifying root causes of recurring errors with proper documentation to enable long term corrective actions. This role will enable an individual to gain both deep and broad experience in the areas of process engineering, data analysis, experimental design, and automation.  This position will also allow time to apply knowledge of coding languages like python and R to real world problems encountered within high paces and dynamic clinical laboratories.  This is considered an onsite role and will require the majority of days to be spent in the Menlo Park office.

Responsibilities:

• Apply sound engineering practices to scale, optimize, and improve molecular biology methods.
• Conduct experiments to identify, isolate, and confirm root causes of process errors in our high-throughput molecular biology lab.
• Develop methods to compile and analyze large amounts of process data to assess for process stability, trending, and areas for improvement.
• Develop and implement software tools to aid in efficient sample processing within the clinical laboratory. 
• Develop, implement, and use software tools to quantitatively analyze process efficiency and sources of error, to require moderate proficiency in R or Python.
• Identify root causes for process and instrument errors and develop short term and long term solutions. 
• Develop effective training plans for clinical personnel on modified/improved workflows.
• Support transfer of new technology from Research and Development teams to the CLIA lab.
• Generate proper documentation for all troubleshooting and qualification.

Requirements:

• Bachelor’s degree or equivalent degree in biology or clinical related sciences
• At least 6 months of experience with molecular biology techniques in a research or clinical laboratory
• Excellent attention to detail
• Effective written and verbal communication skills
• Possess logical troubleshooting skills
• Previous automation or clinical laboratory experience is preferred

Nice-To-Haves:

• Start-up experience
• Experience with next-generation sequencing (NGS)
• Knowledge of molecular oncology
• Experience in a cell-free DNA setting

Benefits And Perks:

• Working alongside brilliant, kind, passionate and dedicated colleagues, in an empowering environment, toward a global vision, striving for a future in which transformative molecular diagnostics can help millions of patients
• Open, transparent culture that includes weekly Town Hall meetings
• The ability to indirectly or directly change the lives of hundreds of thousands patients
• Multiple medical benefit options; employee premiums paid 100% of select plans, dependents covered up to 80%
• Extremely generous Family Bonding Leave for eligible employees (16 weeks, paid at 100%)
• Supplemental fertility benefits coverage
• Retirement savings program including a 4% Company match
• Increase paid time off with increased tenure
• Latest and greatest hardware (laptop, lab equipment, facilities)
• Free daily on-site lunches provided from top eateries
• A variety of perks on campus (state of the art gym, restaurant)
• Free on-site EV charging (compatible with all EVs, including Tesla)

At BillionToOne, we are proud to offer a combination of a (1) base pay range (actual amount offered is based on experience and salary/equity options split that the candidate chooses) (2) generous equity options offering, on top of (3) industry leading company benefits (free healthcare options, 401k match, very generous fully paid paternal leave etc.).

For this position, we offer a total compensation package of $104,322 per year, including a base pay range of $75,029-$85,748 per year.

" data-test-description="">

BillionToOne is an equal opportunity employer. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.

For more information about how we protect your information, we encourage you to review our Privacy Policy.

BillionToOne is a next-generation molecular diagnostics company on a mission to make powerful, accurate diagnostic tests accessible to everyone. Our revolutionary QCT molecular counting technology enhances disease detection resolution by over a thousandfold using cell-free DNA,a breakthrough that has already transformed the lives of over half a million patients worldwide.

Our Impact

Unity Complete™ is the only non-invasive prenatal screen capable of assessing fetal risk for both common recessive conditions and aneuploidies from a single maternal blood sample.

Unity Confirm™ enables non-invasive confirmation for high-risk screening results through the capture of intact circulating fetal cells using BillionToOne’s Fetal Cell Capture™ Technology.

Our Northstar® liquid biopsy test uniquely combines treatment selection with real-time monitoring, giving oncologists unprecedented precision in cancer care.

Our Growth

From $0 to $400M+ annualized revenue run-rate in just 6 years. In 2025, we completed one of the most successful IPOs for a medical diagnostics company, building on nearly $400M in private funding,including our $130M Series D in 2024 and backed by world-class investors including Hummingbird, Adams Street Partners, Neuberger Berman, Baillie Gifford, and Premji Invest.

Our Recognition

Forbes named us one of America's Best Startup Employers for 2025 and we're Great Place to Work certified, with 100% of our people willing to go the extra mile, even as we've scaled to over 700 employees.

Our Future

Headquartered in Menlo Park with facilities in Union City, CA, and a new lab opening in Austin, TX in 2027, we're continuing to push the boundaries of what's possible in molecular diagnostics. We're just getting started.

Ready to help us change the world, one molecule at a time? Learn more at billiontoone.com