Full Stack Engineer (m/w/x)

Tiermedizin neu gedacht - mit dir!

We are seeking a Mid-Senior Full Stack Engineer to take ownership of key services and drive the next phase of our platform's evolution. As a critical member of our engineering team, your role is not just about building features, but applying your  significant software development experience to meaningfully scale our core platform architecture. You will:

• Architect and Implement: Actively contribute to the design and implementation of highly scalable services across the full stack (frontend and backend).
• Drive Technical Ownership: Work closely with product and operations teams to translate complex business needs into robust technical solutions, leading features from concept to production deployment.
• Scale for Hyper-Growth: Address real-world challenges related to performance, reliability, and security as we expand rapidly across Germany and beyond.

This is an incredible opportunity to shape a category-leading healthcare brand and make a tangible technical impact on a rapidly scaling business.

Warum bei Rex? Ganz einfach:

Join Rex, where engineering is key to revolutionizing pet healthcare . We are tackling the complex challenge of digitally transforming the veterinary industry, designing and building a h igh-availability, scalable platform that powers both an exceptional customer experience and efficient, data-driven clinic operations. Having validated our model, we are now entering a phase of rapid, multi-region scaling, requiring r obust architecture, deep technical ownership, and innovative solutions . Come build the system that supports our rapid growth across Germany and beyond.

Spannende Aufgaben warten auf Dich:

As a Mid-Senior Full Stack Engineer, you will be expected to deliver high-quality code and drive technical excellence in the following areas:

• Full-Stack Development & Scaling: Architect, develop, and deploy robust backend services and APIs that power our operational tools, while delivering intuitive and highly scalable frontend experiences for both customers and staff.
• Architectural Contribution: Actively participate in technical design discussions, propose solutions for non-functional requirements (performance, reliability, security), and drive improvements to our core architecture.
• Quality and Maintainability: Uphold rigorous code standards by writing clean, maintainable, and well-tested code. Implement automated testing (unit, integration, and e2e) to ensure quality and prevent regressions.
• Cross-Functional Collaboration: Partner directly with Product, Marketing, and Operations team members to deeply understand business workflows and translate complex problems into effective, user-centric software solutions.
• Elevate Engineering Standards: Champion best practices (e.g., observability, documentation, CI/CD) and foster a culture of technical excellence and continuous improvement.

Du verfügst über folgende Qualifikationen:

We’re looking for engineers who are passionate problem-solvers, not stack purists, but who have substantial experience with modern, high-growth technology stacks. If you’re excited to build great tools, adapt quickly, and care deeply about clean, scalable code— you’ll fit right in.

Must haves
To succeed in this Mid-Senior role, candidates are expected to demonstrate proven capability and confidence in our core technologies:

1. Location Requirement:
   • Must be legally authorized to work and currently based in Germany. This is a mandatory requirement for this role.
2. Experience & Ownership:
   • 4+ years of hands-on, end-to-end experience in software development, ideally within a high-growth, product-driven environment.
   • Proven ability to take full ownership of initiatives and features —from technical design and ideation through to robust production deployment.
3. Required Stack Expertise:
   • Backend: Deep experience building highly performant, scalable services using Node.js and TypeScript (experience with frameworks like NestJS is a significant plus).
   • Frontend: Expertise developing complex, stateful web applications using React and modern frameworks like Next.js .
4. Core Engineering Practices:
   • Strong grasp of modern engineering practices: CI/CD, comprehensive testing strategies (unit, integration, E2E), Event-driven or modular architectures, and API-first design .

Nice to have
These skills would allow you to make an even greater impact immediately:

• Cloud & DevOps: Hands-on experience with cloud environments ( DigitalOcean or AWS ), containerization ( Docker ), and CI/CD pipelines (Github Actions).
• Data Layer: Advanced experience with Relational Databases, particularly PostgreSQL , including query optimization and schema design.
• Asynchronous Processing: Experience with modern job queues, specifically BullMQ or similar robust task processing libraries, for managing background jobs and ensuring system reliability.
• Mobile (A Strong Asset): Experience with React Native for cross-platform application development.

Mindset we are looking for:

• You see technologies as tools—not constraints—and can choose the right one for the job.
• You’re comfortable jumping between stacks and solving complex, cross-functional challenges.
• You value quality, simplicity, and iterative development that delivers incremental business value.

Dann bist du bei uns genau richtig!

The Pack.
Join an ambitious team of extraordinary people and grow in an environment that values ownership, autonomy, and constructive feedback.

Impact.
Be part of shaping a young, fast-growing startup and redefine the future of animal health with us.

Growth.
Join our initial core engineering team – take ownership early and accelerate your personal and professional development.

Appreciation.
We value your contribution with a competitive compensation package and a personal budget for things like fitness or mental well-being.

Well-being.
Healthy body, healthy mind – enjoy healthy snacks & drinks in our Berlin (Mitte) office, flexible (remote) work options, and regular team events & dinners.

Pet Care.
Your pet is family – bring them to the office anytime!

Über uns

Rex ist die perfekte Mischung aus moderner Tierarztpraxis und dynamischen Technologie-Startup. Wir sind ein 2021 gegründetes, junges Unternehmen aus Berlin und haben es uns zur Aufgabe gemacht, ein innovatives Umfeld zu schaffen, um die medizinische Versorgung unserer vierbeinigen Familienmitglieder für Tierärzt:innen, TFAs und Tierhalter:innen zu optimieren.

Wir wollen die tierärztliche Betreuung von Grund auf neu gestalten, wobei wir uns zum einen auf die Zufriedenheit und die Entwicklungsmöglichkeiten unseres Teams und zum anderen auf ein verbessertes und digitaleres Praxiserlebnis für Halter:innen konzentrieren. Der Schwerpunkt unserer Arbeit liegt dabei auf reibungsloseren Abläufen und besseren Karrieremöglichkeiten - ein glücklicheres und unterstütztes Team versorgt die Tiere, die wir alle lieben, besser und umfassender.

In unseren Praxen setzten wir auf eine angenehme Atmosphäre durch warme Farben und sanfte Lichtkonzepte, um so eine beruhigende Umgebung zu schaffen. Gleichzeitig gibt es bei uns modernes medizinisches Equipment wie digitales Röntgen, Inhouse - Labore und Ultraschall. Wir geben unserem Personal die notwendigen Mittel an die Hand, um eine hervorragende verterinärmedizinische Versorgung unserer Patienten sicher zu stellen.