Sr. Software Engineer

Karius•Redwood City, CA

23h•Hybrid

About The Position

Karius is 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. 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. This is a temporary/contract position up to 6 months. 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.

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
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.

Nice To Haves

Experience in the life sciences or healthcare domain, especially next-generation sequencing, diagnostic laboratory environments, or related regulated settings, is highly desirable

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.