Founding software engineer

Lucis; Île-de-France; Sur place; EUR 60 000 - 80 000; Plein temps

Résumé du poste

A health-tech startup is looking for a full stack software engineer to join as a founding engineer. This role requires expertise in building SaaS applications and an entrepreneurial mindset. You'll design and implement features that impact health, own critical code, and collaborate with experts in a mission-driven environment. Fluency in English is essential, and knowledge of French is a plus.

Prestations

Equity ownership

Budget for personal care and development

Quarterly retreats in Europe

Hardware of your choice

Qualifications

• 7+ years building production SaaS or B2C apps including at least one 0→1 journey.
• Must have expertise in multiple layers: front-end, API, data model, and DevOps.
• Experience with AI tools and fluent in Cursor PRD files.

Responsabilités

• Design and build full-stack features using TypeScript/Next.js.
• Own cloud infrastructure and CI/CD with security-first mindset.
• Collaborate with medical advisors to translate science into algorithms.

Connaissances

Full stack development

SaaS experience

Agile development

AI systems

PostgreSQL optimization

Outils

AWS

TypeScript

Docker

CI/CD tools

Description du poste

The role

We’re looking for a full stack software engineer, product-minded, with entrepreneurial DNA and early stage 0→1 experience. It’s a plus if you are passionate about digital health and longevity.

You’ll join as a founding engineer and shape a product that could add healthy years to millions of lives. As the first full-time founding engineer, you will:

• Own mission-critical code from day 1, not tickets
• Shape product and tech choices that will impact thousands of users, starting with yourself
• Solve real-world health data, privacy, and UX puzzles at European scale
• Have a unique opportunity to shape the vision and direction of the company

Our culture

We are building fast, for the long term.

1. Rigor without ego: audits, science, and code deserve the same high bar.
2. Default to action: small PRs, short feedback loops.
3. Radical ownership: you break it, you fix it (and write the doc).
4. Play long games: we’re building a 100-year company to help people live 100 healthy years.

What we offer

• Equity that matters: real ownership at the inflection point. With top-tier salaries.
• Budget for personal care, personal development, and health stipends (we pay your own Lucis tests).
• Quarterly in-person retreats in Europe. We repeat the YC experience every 3 months.
• Hardware of your choice, modern dev-tool stack.
• The chance to directly improve thousands of lives, starting with your own, through smarter preventive care. We are the average of the person we spend our time with.

What you will do

Core responsibilities

• Design and build full-stack features (TypeScript/Next.js, NestJS, Postgres, Prisma).
• Own cloud infra (AWS) and CI/CD (GitHub Actions, AWS CDK) with a security-first mindset. Security is core of what we do (HDS compliant).
• Collaborate with medical advisors, the AI and data team, and product and design to translate biomarker science into reproducible algorithms.
• Architect highly available and scalable systems, with expertise in PostgreSQL performance optimization. Contribute to the scalability of our tech stack. Design and maintain improved versions of our stack, implement caching.
• Maintain strict compliance with HDS and GDPR regulations through robust security measures.
• Drive engineering rituals. Drive continuous improvement through Agile development practices and cross-team collaboration.

Our tech stack

• Typescript mono repo
• PNPM workspaces
• ES linting
• Storybook
• React, NestJS (Node)
• AWS, Fargate, Infra as code AWS CDK
• Docker
• Prisma, Postgres db
• CI/CD Github Actions
• Tailwind

You’ll thrive here if you

• Have 7+ years building production SaaS or B2C apps, including at least one 0→1 journey.
• Can move vertically: front-end → API → data model → DevOps, shipping quality code in each layer. You have 2 core expertises.
• You have experience building systems enabled by AI tools. You are fluent in Cursor PRD files.
• Entrepreneurial, low-ego mindset. You want to build a massive company with massive impact.
• Cautious about your health, actively doing sport. Care about health: you read PubMed abstracts for fun, or track your own biomarkers and metrics.
• Fluent in English. French is a bonus.
• You have led a team before. You remain hands-on more than 80% of your time in your current job.