Software Engineering Intern

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 seeking a passionate and motivated Software Engineering Intern to join our dynamic engineering team for a summer internship program. As an intern, you'll work alongside experienced engineers, clinicians, and computational biologists across multiple product lines, contributing to meaningful projects that help scale personalized genomic medicine to millions of patients. This is an excellent opportunity to gain hands-on experience in healthcare technology while making a real impact on patient care. This is a full-time hybrid position (onsite 2-3 days/week).

• Portal Enhancements: Develop new features for our provider and patient portals, such as implementing automated notification systems or creating intuitive data visualization dashboards for test results
• AI-backed Services: Create new software services that are AI driven such as insurance card scanning or lab monitoring

These projects will give you hands-on experience while contributing to meaningful improvements in healthcare delivery.

• →Write clean, well-documented code following team standards and best practices
• →Participate in code reviews and contribute to technical discussions
• →Create and maintain comprehensive test suites for your code
• →Document your work and contribute to technical documentation
• →Present your projects and findings to the team

• Currently enrolled in a Bachelor's or Master's degree program in Computer Science or related field
• Demonstrated programming experience with Python through coursework or projects
• Basic understanding of databases (SQL) and web development concepts
• Strong problem-solving skills and eagerness to learn
• Clear written and verbal communication skills
• Available for full-time summer internship (10-12 weeks)
• Excited about working in-person with our team in Menlo Park (2-3 days/week)
• Passionately curious about the fields of healthcare and biotechnology

• Previous project experience (personal, academic, or hackathon projects)
• Familiarity with any web framework (Django, Flask, etc.)
• Basic understanding of version control (Git)
• Experience working with LLMs (GPT, Claude, etc.)
• Experience working with REST APIs
• Basic understanding of cloud services concepts
• Experience with prompt engineering or LLM application development

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

From $0 to $150M+ in Annual Recurring Revenue in just five 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.

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.

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