Senior Fullstack Engineer

Parallel; Paris; On-site; EUR 90,000 - 130,000; Full time

Benefits offered by this job

Premium health insurance

Swile meal vouchers

Latest Apple equipment

Paris office

Job summary

Parallel in Paris is hiring a Senior Full-Stack Engineer to scale our AI agent platform for healthcare. You will own the full technical stack from backend services to user interfaces, shape architecture, and make key product decisions.

You will build robust, secure systems, ship LLM-powered agents, collaborate with the CTO, and drive tooling, CI/CD, observability, and data pipelines to run in hospital environments.

Qualifications

• 5+ years of full-stack experience.
• 2+ years building with Node.js/TypeScript and React.
• You've worked with LLMs and AI agents.
• Comfortable with infrastructure and deployment (AWS, Docker, Terraform, Kubernetes, GitHub Actions).
• You care about product and push back when needed; autonomous and pragmatic.
• French-speaking; graduate of a top engineering school.

Responsibilities

• Own the full lifecycle of major features from spec to production monitoring.

Skills

Node.js & TypeScript

NestJS

Express

Prisma

Postgres

React

TanStack

Tailwind

LLMs

AI agents

AWS

Docker

Terraform

Kubernetes

GitHub Actions

CI/CD

Observability

Education

Top engineering school

Tools

LangChain

Hugging Face

Job description

At Parallel, we build AI agents to help healthcare facilities automate their administrative processes and unlock additional revenue, starting with medical coding.

Today, up to 25% of healthcare spending is lost in manual, repetitive administrative work. Legacy software hasn't helped, it's made things slower, more complex, and more frustrating for care teams.

We believe AI agents can change that. Our technology combines Large Language Models with system-level automation to handle real work inside existing hospital tools. No integrations, no disruption.

Our first agent automates coding workflows and frees up time for medical staff to focus on patients.

We launched in 2024, are backed by top investors (Index, Frst, Y Combinator, Hexa, Kima Ventures, Better Angle), and we're just getting started.

The future of healthcare isn't just digital - it's automated. Come help us build it !

Context

We're at a pivotal moment. We've closed a $20M Series A with Index Ventures, we're deployed in 40+ hospitals, and we're scaling fast. The company was built by Paul Lafforgue (Polytechnique, ex-Meta, ex-McKinsey) and Chris Rydahl, whose previous company Hublo became Europe's largest healthcare staffing platform. We're 15 people, based in Paris.

We're now hiring a Senior Full-Stack Engineer to help us scale - not just to write code, but to shape our architecture, make key product decisions, and define our engineering culture.

Your mission

Own the full technical stack - from core backend services to user-facing interfaces - and help deploy reliable AI agents in hospitals.

Concretely, you will:

• Build production-grade systems, not prototypes - robust, secure, and HDS-compliant, designed to run in demanding hospital environments

• Ship and iterate on LLM-powered agents that automate complex end-to-end workflows

• Work alongside the CTO to make the right architecture decisions, balancing speed and long-term scalability

• Build interfaces that doctors and administrative operators actually want to use - understanding their pain points, not just closing tickets

• Lay the engineering foundations: CI/CD, observability, internal tooling, code quality standards

Outcomes

In your first months, we expect you to:

• Own the full lifecycle of major features - from spec to production monitoring

• Design a modular backend architecture that supports multiple clients with complex, custom business rules

• Deploy AI agents in production with a high reliability bar

• Build and maintain solid data pipelines between hospital systems and our stack, HDS-compliant

• Improve team velocity through better tooling, CI/CD, and observability

This job is for you if:

• You have 5+ years of full-stack experience

• You're strong in Node.js & TypeScript (NestJS, Express, Prisma, Postgres) and React (TanStack, Tailwind)

• You've played with LLMs and AI agents - whether on side projects or professionally (LangChain, Hugging Face)

• You're comfortable with infrastructure and deployment (AWS, Docker, Terraform, Kubernetes, GitHub Actions)

• You care about the product, not just the code - you push back when something doesn't make sense, and you propose solutions proactively

• You're autonomous and pragmatic - done beats perfect, especially at this stage

• You're French-speaking

• You graduated from a top engineering school

Hiring process

1. Quick call with Chris, our CTO

2. Case study at our Paris office

3. Meeting with Paul, our CEO

4. Drinks with the team

Why join us?

• Real traction. Seed and Series A closed in under a year, with Index Ventures on the cap table. This isn't a maybe - it's a company that's moving.

• A problem worth solving. Cutting hospital admin directly gives time back to care teams. The impact is tangible.

• A genuinely different technical approach. Agents that work on top of existing systems without heavy integration is a real competitive edge - and you'll be the one building it.

• A team that has done it before. The founders have built and scaled before (Hublo, Meta, McKinsey). High standards, low ego.

• Actual ownership. You won't be handed a backlog. You'll co-build the architecture and set the engineering culture from the ground up.

• Competitive salary and equity package, premium health insurance (Alan), Swile meal vouchers, latest Apple equipment, Paris office (Strasbourg Saint-Denis).

We care about who you are, not just what's on your CV.

If you're drawn to what we're building but don't meet every requirement, we still want to hear from you. Studies show that women in particular tend to apply only when they meet 100% of the criteria. If that's you, please don't let that hold you back. We'd love to receive your application.