Senior/Staff Software Engineer, Oncology (Full-Stack)

USD 180k - 265k
React Python PostgreSQL Flask Unity Django AWS Vue.js TypeScript

Do you want to join one of the fastest-growing molecular diagnostics companies to help transform prenatal and oncology diagnostics that can affect millions of patient lives?

BillionToOne, ranked at the top 5% of Y Combinator companies with $300M+ in funding from prominent VC firms, has developed a DNA molecular counter that increases cfDNA diagnostic resolution by over 1,000x. BillionToOne's first product, UNITY™, is the first and only non-invasive prenatal test that can directly screen an unborn baby and assess its risk for common and severe recessive gene disorders and chromosomal abnormalities, as well as fetal sex and fetal antigens, from a single tube of blood from the pregnant mother without paternal testing.

In 2023, BillionToOne launched two liquid biopsy products that will markedly improve oncology treatment and care. With Northstar Select™, clinicians will be able to select cancer therapies that will be most effective to each patient based on their individual genetic makeup. Northstar Response™ will enable clinicians to monitor a patient’s early response to these cancer therapies, by measuring minute changes in their ctDNA, which can reduce ineffective treatments and unwanted toxicity, lower costs, and substantially improve clinical outcomes.

We are currently looking for a high-performing Senior/Staff Software Engineer to join our dynamic software engineering Oncology team. This is a full-stack role with a slight emphasis on front-end. Software engineers at BillionToOne work in highly collaborative and interdisciplinary teams of clinicians, computational biologists, and other engineers to robustly scale personalized genomic medicine to millions of patients. If you have experience performing in a full life-cycle development, love seeing your work positively affect your colleagues and patients, and thrive in a fast-paced entrepreneurial environment, this could be a great opportunity for you. In this role, you can have an impact both through many small tools and large product development. This is a remote position, but you may also work from our office in Menlo Park or Union City, CA if you’re locally-based.

Projects you may work on include:

  • Build a seamless digital experience so clinicians and patients across a diversity of care centers and socioeconomic status can have access to BillionToOne’s highly complex genetic testing
  • Help digitize laborious and error-prone paper-based workflows at busy OBGYN clinics
  • Enable better transfer of care through portable electronic medical records

Technologies we use include React, Typescript, Python, Django, Postgres, AWS


  • Build and maintain robust and rich applications using React, Typescript, python, Postgres, and other libraries/frameworks.
  • Collaborate with Design and Product management to deliver delightful experiences for patients and providers.
  • Comfortable working in a cloud-first environment with experience with AWS services like ECS, S3, AWS-Batch, EC2 and AWS Lambda
  • Foster a knowledge sharing culture within the team, contributing to the growth and development of colleagues through mentorship and collaborative learning.
  • Demonstrate a creative and out-of-the-box mindset, offering innovative solutions and approaches to complex technical challenges.
  • Prioritize quality by writing comprehensive unit / integration / end-to-end tests and ensuring adequate test coverage across all components and modules. Highly skilled in writing technical documentation and validation reports that assure correct functionality of medical informatics systems.
  • Demonstrate a strong sense of ownership and take responsibility for end-to-end project delivery. The ideal candidate will thrive in an environment where they have the autonomy to make informed decisions and take the initiative to drive projects forward.
  • Confidently challenge ideas and assumptions from stakeholders when necessary, while at the same time, leverage their expertise and insights to improve the overall solution.
  • Prioritize collaborative and cross-functional development, actively seeking input from team members and valuing diverse perspectives. Put the success of the team and the project above individual agendas, fostering a positive and inclusive work environment


  • Minimum of 5 years of professional software development experience, with a strong track record of delivering complex projects successfully
  • Expert at full-stack web application development, especially front-end frameworks like React or Vue.
  • Excellent communication and collaboration skills, with the ability to work effectively in a team-oriented environment.


  • Ability to wear hats across multiple functions, such as UI/UX design
  • Experience developing with python backends (e.g. Django or Flask)
  • Previous startup or entrepreneurial experience
  • Familiarity with healthcare data and standards like FHIR and HL7
  • Experience with medical software and authoring technical verification / validation reports.

Benefits And Perks:

  • Working with a team of ‘rockstars’ who bring out the best in everyone
  • 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 at 80%
  • Extremely generous Family Bonding Leave for new parents (16 weeks, paid at 100%)
  • Retirement savings program including a 4% Company match
  • Free daily on-site lunches provided from top eateries
  • Latest and greatest hardware (laptop, lab equipment, facilities)
  • 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 parental leave etc.). Please apply even if you don’t meet every requirement, we’d love to take a look at your profile! 

For this position, we offer a total compensation package of $265,000, including a base pay range of $180,000-$200,000 per year.

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.

There are more than 50,000 engineering jobs:

Subscribe to membership and unlock all jobs

Engineering Jobs

50,000+ jobs from 4,500+ well-funded companies

Updated Daily

New jobs are added every day as companies post them

Refined Search

Use filters like skill, location, etc to narrow results

Become a member

🎉 12 people have signed up in the past 7 days.

Overall, over 80% of customers chose to renew their subscriptions after the initial sign-up.

Cancel anytime / Money-back guarantee