Senior AI Engineer I

Menlo Park, CA

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. As BillionToOne scales rapidly, we are building a world-class Commercial Data & Applied AI team. We are currently seeking a highly motivated Senior AI Engineer I to support the design and implementation of AI and automation solutions that optimize operations across our commercial, billing, and customer experience teams. This is a full-time senior role for engineers excited about applying LLMs, AI, and automation to real-world business challenges in healthcare. You will have the opportunity to join a new team and help shape the vision and culture. You will collaborate cross-functionally with stakeholders in Sales, Marketing, Revenue Operations, Billing, Customer Experience, and IT to identify high-impact opportunities for AI-driven solutions that improve scalability and efficiency. We are builders at heart. We value a strong sense of ownership, intellectual curiosity, and a bias toward action. This is a hybrid role requiring 2-3 days per week on-site in Menlo Park with the team. Responsibilities:

• Build and deploy LLM-powered applications (retrieval systems, AI agents, workflow automation, vector storage) that integrate with internal systems and data sources
• Partner with business stakeholders to identify automation opportunities, scope requirements, and define success metrics
• Build lightweight data pipelines and analytics to support AI applications and measure their impact
• Own projects end-to-end: from prototyping and iteration through production deployment and monitoring
• Establish best practices for prompt engineering, evaluation, and responsible AI use as the team scales
• Develop and lead internal training sessions on LLM fundamentals, prompt engineering, and AI-assisted development tools

Qualifications:

• 5+ years of experience in software engineering, data science, or ML engineering
• Hands-on experience building applications with LLM APIs (OpenAI, Anthropic, etc.)
• Strong Python proficiency and comfort with SQL and relational databases
• Experience deploying and maintaining production systems
• Familiarity with AWS
• Excellent communication skills and ability to translate business problems into technical solutions
• Self-directed and comfortable with ambiguity in a 0-to-1 environment

Nice-To-Haves:

• Previous entrepreneurial experience
• Experience with retrieval architectures, vector databases, and embedding models
• Familiarity with agent frameworks or workflow orchestration tools
• Experience with traditional ML frameworks (scikit-learn, PyTorch, TensorFlow)
• Prior work in healthcare, biotech or other regulated industries

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 new parents (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 hardware (laptop lab equipment facilities)
• 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 offer:

Base pay range (actual amount offered based on experience & salary/equity options split chosen by candidate)

Generous equity options offering

1. Corporate bonus program

Industry leading company benefits (free healthcare options 401k match fully paid parental leave etc.)

For this position: Total compensation package: $280705 per year Base pay range: $174241 - $200641 per year

Location

Menlo Park CA (hybrid role requiring 2–3 days onsite per week)

Remote Work Mention

No explicit mention of remote work; role is hybrid onsite.

Employment Type

Full-time senior role.

Experience Level

Senior level (5+ years experience required).

Salary Information

Total compensation package: $280705/year Base pay range: $174K - $200K/year

Comprehensive Skills List

Technical Skills:

• Software engineering / data science / ML engineering (5+ years)
• Building applications using LLM APIs (OpenAI Anthropic etc.)
• Python programming proficiency
• SQL & relational databases expertise
• Production system deployment & maintenance experience
• AWS familiarity
• Retrieval architectures & vector databases (nice-to-have)
• Embedding models (nice-to-have)
• Agent frameworks or workflow orchestration tools (nice-to-have)
• Traditional ML frameworks: scikit-learn PyTorch TensorFlow (nice-to-have)

Soft Skills:

• Excellent communication skills translating business problems into technical solutions
• Self-directed working style comfortable with ambiguity

Additional Qualifications: Prior entrepreneurial experience Experience in healthcare biotech or regulated industries

Application URL

https://www.billiontoone.com/careers/open-positions