Full-Stack Engineer

Job Description

Senior Full-Stack Engineer (Web)

Location : Hybrid (San Francisco) / Remote (US / Canada)

Employment Type : Full-time

About the Opportunity

At Principled, we are working with a stealth-stage HealthTech company that's reinventing primary care with AI-driven longevity tools. This team is combining advanced diagnostics with personalised care plans to proactively support long-term health. You'll be joining a small, high-performing engineering team led by repeat founders (including two prior telehealth unicorns) and an accomplished medical leadership team (think NYT bestsellers and world-class researchers). Now's your chance to help build the technical foundation of a product that's reshaping how we think about everyday healthcare.

What You'll Be Doing

• Build and scale full-stack features across web and mobile using React, TypeScript, and Next.js on the frontend
• Work with Node.js, GraphQL, and Postgres on the backend to deliver performant, secure APIs and data models
• Translate clinician workflows and complex lab data into elegant, consumer-ready UX
• Contribute across the stack-from UI implementation to schema design with Prisma, CI / CD, and AWS-based infrastructure.
• Collaborate on shared design systems, backend standards, testing strategies, and engineering culture

What You Bring

Why Join?

Ground-floor impact : Join early and help shape both the product and company from day one.

Real-world innovation : Build AI-powered tools that genuinely improve health and longevity.

Own the frontend : Lead web UX and turn complex clinical data into simple, beautiful interfaces.

Meaningful equity : Get real ownership in a startup with strong backing and high upside.

Move fast, stay focused : Work in a small, agile team without corporate overhead.

Bay Area + balance : Collaborate in-person in SF 2-3 days / week, with modern flexibility and remote opportunities within the US / Canada.

Application Process

Principled Careers is managing recruitment for this role. We take a values-aligned, transparent approach and ensure candidates feel supported every step of the way. Expect a structured and respectful process, including an initial screen, technical or role-aligned assessment, and culture conversation.

Apply now if you're ready to work at the intersection of technology and learning or reach out to Principled Careers to learn more about similar opportunities.