Full Stack AI Engineer (all) - React / NodeJS

Personio; München; On-site; EUR 110,000 - 150,000; Full time

Job summary

Personio is hiring a Full Stack AI Engineer to join our engineering team and build end-to-end solutions for our digital health platform. You will design and implement client-side and server-side applications, delivering seamless experiences while ensuring robust backend infrastructure.

You will work on responsive mobile-first interfaces using React and React Native, integrate with APIs, design scalable architectures, and contribute to data processing pipelines and real-time features in a

Qualifications

• Bachelor's degree or equivalent practical experience in CS/SE.
• 7+ years of full-stack development, including frontend and backend.
• Experience with growth techniques and testing frameworks.
• Strong performance optimization and monitoring skills.
• Mobile-first development and responsive design experience.

Responsibilities

• Build responsive mobile-first UIs with React and React Native.
• Integrate frontend with backend APIs and services.
• Design scalable full-stack architectures for web and mobile.
• Develop data processing pipelines and background jobs.
• Implement real-time features using WebSockets and secure CI/CD pipelines.

Skills

JavaScript/TypeScript

React

React Native

Expo

CSS/Styling

Build Tools

WebSockets

Node.js

Express.js

MongoDB

Redis

Education

Bachelor's degree in Computer Science, Software Engineering, or related field OR equivalent work experience

7+ years of full-stack product development experience

Tools

MongoDB

Redis

Express.js

Webpack / Vite

Docker

Kubernetes

Job description

Who we are looking for

We are seeking a versatile Full Stack AI Engineerto join our engineering team to build end-to-end solutions that power our digital health platform and help the platform to grow. This role involves designing and implementing both client-side and server-side applications, creating seamless user experiences while ensuring robust backend infrastructure.

Your mission

Development

• Build responsive and intuitive mobile first user interfaces using React and React Native


• Implement modern UI/UX designs with attention to accessibility and performance


• Integrate frontend applications with backend APIs and services


• Design and implement scalable backend architectures


• Optimize application performance and implement efficient state management


• Develop cross-platform mobile applications using Expo and React Native


• Build data processing pipelines and background jobs

Engineering Tools

• AI-assisted development: Ability to effectively use AI tools in daily development work

Database & Data Management

• Design and optimize database schemas (MongoDB, Redis)


• Implement data migration strategies and ensure data integrity


• Monitor and optimize database performance

System Architecture & Integration

• Design full-stack architectures that scale from web to mobile


• Integrate third-party APIs and services


• Implement real-time features using WebSockets

Infrastructure & Deployment

• Deploy and manage applications in cloud environments (AWS, GCP)


• Implement containerization with Docker and Kubernetes


• Monitor system performance and troubleshoot issues across the stack


• Ensure security best practices and compliance


• Build and maintain CI/CD pipelines

Collaboration & Quality

• Be fully responsible for the quality of the produced outcome


• Work closely with product managers, designers, and other engineers


• Participate in code reviews and maintain code quality standards


• Write comprehensive technical documentation

Your background

Education & Experience

• Bachelor's degree in Computer Science, Software Engineering, or related field OR equivalent work experience with strong technical portfolio


• 7+ years of full-stack product development experience


• Experience with growth techniques


• Experience with testing frameworks (unit, integration, end-to-end)


• Experience with performance optimization and monitoring tools


• Experience with mobile-first development and responsive design

Frontend Technical Skills

• JavaScript/TypeScript: Expert-level proficiency in modern JavaScript (ES6+)


• React: Strong experience with React, hooks, context API, and state management


• CSS/Styling: Proficiency in modern CSS, styled-components, or similar


• Build Tools: Webpack, Vite, or similar bundling tools


• Expo: Familiarity with Expo framework and development workflow


• React Native: Experience building cross-platform mobile applications

Backend Technical Skills

• Node.js: Strong server-side JavaScript/TypeScript development


• Express.js: Experience building RESTful APIs and web services


• Databases: MongoDB (primary), Redis for caching


• API Development: RESTful APIs


• Authentication: JWT, OAuth, session management

Soft Skills

• Strong problem-solving and analytical abilities


• Good communication and teamwork abilities


• Eagerness and passion to work in agile and lean development environments


• Deep product and customer-centric — always advocate for user needs and deliver delightful, impactful experiences

Preferred Qualifications

• Experience with healthcare or regulated industry applications


• Understanding of accessibility standards


• Familiarity with design systems and component libraries


• Experience with mobile-specific features (push notifications, offline storage)


• Knowledge of mobile performance optimization

Why us?

• Top Tech company in Digital Health:A dynamic, high-growth environment where everyone in the team depends on each other's performance. You can see your impact. We learn and develop quickly.


• True impact in healthcare: What we are building with our brite platform is unique worldwide, ambitious, and could have a huge impact on billions of people who are ill or interested in health.


• International team:We are 14 nationalities working across Europe. We bring different mentalities and cultures with us, but we are all aligned towards our grand vision.

Hiring Process

• Recruiter Screening: Technical phone/video introductory and experience call


• Leadership Interview:Discussion focused on leadership principles, values, and cultural fit.


• Technical Deep Dive:Live coding session covering React, Node.js, and database design