Sr. Software Engineer

About Karius Karius is a life science, venture-backed clinical metagenomics company, focused on elevating patient care through microbial insights. We are committed to advancing diagnostic science and technology to optimize the diagnosis and treatment of infectious diseases. Through the use of genomics and AI, we are driven to improve the diagnostic landscape for infectious diseases. Karius delivers unprecedented diagnostic insight detecting microbial cell‑free DNA circulating in the body to assist physicians to make rapid treatment decisions. Position Summary We are building and operating a unique software stack of cloud infrastructure, software services, APIs, web and mobile interactive interfaces, and AI‑driven data analytics pipelines to deliver life‑saving results in the highly complex infectious disease landscape. We believe the success of Karius’ products is driven by both our unique technology and the elegance of the software solution. We seek talented and passionate individuals who want to be part of this impactful journey reaching the team’s ambitious goals, far beyond what any single individual could accomplish. Duration This is a temporary/contract position up to 6 months. Why Should You Join Us? Karius aims to conquer infectious diseases through innovations around genomic sequencing and machine learning. The company’s platform is already delivering unprecedented insights into the microbial landscape, providing clinicians with a comprehensive test capable of identifying more than a thousand pathogens directly from blood, and helping industry accelerate the development of therapeutic solutions. The products Karius offers today are some of the most advanced solutions available to physicians who aim to deliver better care to many otherwise ineffectively treated patients. Our tests are the result of some incredible work done by our scientists, statisticians, engineers, and physicians, all driven by the same mission. You, as part of the Karius team, will be able to see how directly your work has a life‑changing impact on people, and at scale. Reports to Sr. Director, Engineering Location Redwood City, CA (Hybrid) or Remote (USA) Primary Responsibilities Understand user needs and objectives by collaborating closely with cross‑functional groups across Karius, including Engineering, Software Products, Analytics, Lab Operations, and other business partners. Develop and share software subsystem designs that address user needs and enable teams to achieve their objectives. Lead the implementation and end‑to‑end testing of software solutions and components, including driving user acceptance. Own software subsystems, API sets, or user applications, serving as the go‑to subject matter expert for assigned areas. Develop strong expertise in the corresponding business domain to ensure software solutions are aligned with operational and user needs. Contribute to the continuous improvement of the engineering lifecycle by leading enhancements to tools, processes, and ways of working. Help advance a high‑performing engineering culture through close collaboration, engagement, and partnership with the broader engineering team to solve technical challenges as they arise. What’s Fun About the Job? Karius is operating at the edge of what is now known to be possible in diagnostics. With that, comes a wave of new and incredible challenges and opportunities. To deliver on that value, you will be tapping into some of the most advanced technologies, architecting and innovating where the current solutions simply don’t suffice. You will get to see how much your work really matters. Travel No travel required. Physical Requirements Subject to extended periods of sitting and/or standing, vision to monitor and moderate noise levels. Work is generally performed in an office, lab or clinical environment. Position Requirements BS or MS degree in Computer Science, Software Engineering, Electrical Engineering, Bioengineering, or a related technical field involving algorithms or coding, such as physics or mathematics. 5+ years of software engineering experience designing, developing, and maintaining full‑stack solutions in a production environment. Advanced knowledge and 3+ years of experience implementing production software using TypeScript. Strong TypeScript and Node.js engineering experience, including building and maintaining substantial TypeScript services in production. Experience designing and operating microservices‑based systems, with a clear understanding of service boundaries, contract evolution, error handling across service calls, and observability. Production experience with Kafka or a comparable event‑streaming platform, including topic design, partition strategy, consumer group behavior, idempotency, ordering guarantees, and handling delayed, failed, or unprocessable messages; Confluent experience is a plus. Experience designing PostgreSQL database schemas, with a strong understanding of transactions, indexing, and migration strategy. Knowledge and hands‑on experience developing and operating distributed cloud‑based software systems using technologies such as Docker, Kubernetes, Kafka, GraphQL, and AWS or equivalent cloud platforms. Experience operating services in AWS or similar environments, including the ability to navigate services such as EKS, RDS, S3, CloudWatch, IAM, and troubleshoot issues across application and infrastructure boundaries. Experience with unit testing frameworks such as Jest, Vitest, or similar. Hands‑on experience with end‑to‑end testing frameworks such as Playwright, Cypress, Selenium, or similar. Strong test design skills, including the ability to translate acceptance criteria or user stories into a balanced coverage strategy across unit, integration, and end‑to‑end testing. Hands‑on experience with modern AI tools such as Claude, Cursor, or similar. Familiarity with requirements management tools such as JAMA. Experience in the life sciences or healthcare domain, especially next‑generation sequencing, diagnostic laboratory environments, or related regulated settings, is highly desirable. Personal Qualifications Strong commitment to engineering quality, including testability, maintainability, and reliability. Strong written communication skills, with the ability to create clear design documents, PR descriptions, test cases, and technical documentation. Ability to work across systems and integration points, including troubleshooting issues that span multiple services, applications, or teams. Ability to operate effectively in ambiguous situations by asking clarifying questions, identifying assumptions, and helping define practical solutions. Disclaimer The above job description is intended to describe the general nature and level of work being performed by individuals assigned to this position. It is not intended to be an exhaustive list of all duties, responsibilities, and skills required. Responsibilities and duties may change or be adjusted to meet the needs of the company, and additional duties may be assigned as necessary. The job description is subject to change at any time at the discretion of Karius. Equal Opportunity Employer At Karius, we value a diverse and inclusive workplace and provide equal employment opportunities for all applicants and employees and are committed to honor and invest in the full diversity of people, in our hiring, recruiting and development of employees across the Company. All qualified applicants for employment are encouraged to apply and will be considered without regard to an individual’s race, color, sex, gender identity and gender expression (including transgender individuals who are transitioning, have transitioned, or are perceived to be transitioning to the gender with which they identify), religion, age, national origin or ancestry, citizenship, physical or mental disability, medical condition, family care status, marital status, domestic partner status, sexual orientation, genetic information, military or veteran status, or any other basis protected by federal, state or local laws. If you are unable to submit your application due to a disability, please contact us at View email address on click.appcast.io and we will accommodate qualified individuals with disabilities. $72 - $84 an hour #J-18808-Ljbffr StartX.