Internship Backend Engineer Jobs in Wisconsin (NOW HIRING)

Are you passionate about technology with a purpose? Want to make a meaningful impact on people's health? Want to work in an AI-native company? At Relu, we're growing - and we're looking for someone like you. We're looking for a Full-Stack Engineer to join our Platform team; the web app, 3D viewer, workflow automations, integrations and infrastructure that hundreds of dental professionals rely on every day. You will:

• Build and scale our web platform used by thousands of users globally, and ensuring that it can handle the growing amount of users & orders.
• Build agents that run the digital backbone of a dental lab; automating everything from patient scan intake and order entry to customer emails and 3D print queues.
• Think from a user’s perspective to design & implement slick user interfaces.
• Ship features across our 3D mesh viewer; editing tools, visualization controls and model handling.
• Build and harden integrations with scanners, printers, CAD/CAM partners, ERPs and more.
• Improve reliability and observability across the platform.

We're open on experience level. What matters is that you have some real hands-on experience: an internship, your own projects, or applied work with others. Whether you're fresh out of your Master's or have a few years of front-end work behind you, if you're smart and ready to contribute, we want to hear from you.

• You can find your way around both a frontend (TypeScript/React) and a backend (Python/FastAPI) codebase. You don't have to be expert in both, but you're not afraid of either.
• A working understanding of databases and APIs, and the curiosity to reason about *why* something behaves the way it does (transactions, race conditions, third-party integrations with auth and rate limits).
• You can debug: when something breaks, you dig in with logs, metrics and error-tracking tools rather than guessing.
• You care that the code you ship works and doesn't break things around it.
• You have an eye for design, and think from a user-perspective to build excellent UX.

• Experience with 3D graphics on the web (Three.js / WebGL), meshes, or medical/scientific visualization.
• Familiarity with cloud infrastructure and DevOps (AWS, CloudFront, CI/CD, observability tooling).
• Exposure to dental, medtech or CAD/CAM domains.
• Comfort building with and alongside AI/LLM tooling.

• You think sharply, and you'll be surrounded by people who do the same.
• You're an independent thinker: you don't blindly implement tickets. You think through the consequences and connections of your work and find smart solutions to problems.
• You're reliable — people can count on you to see things through.
• You communicate. You pick up a ticket, ask questions when in doubt, and then execute until it's done — without breaking other things along the way. We don't work in silos.

• Frontend: Vue.js, TypeScript, Three.js
• Backend & APIs: Python, FastAPI
• Data & Databases: PostgreSQL, SQLAlchemy
• Infrastructure & DevOps: AWS, Terraform, CI/CD, Docker, Kubernetes
• Observability: Sentry, Grafana, Faro RUM
• Integrations & Partners: 3Shape, iTero, Medit Link, Formlabs, and a growing list of scanner/printer/CAD-CAM APIs

• MSc in Computer Science or something related
• Experience with front- and/or back-end related work
• Fluent in English (written and spoken)
• Valid work authorization in Belgium
• Able to work from our Leuven office at least 3 days per week

• A mission that matters: We’re transforming dental care to make high-quality dentistry accessible globally.
• A fast-moving team that ships: A collaborative, ambitious team that executes at hyper-speed while keeping the day-to-day genuinely fun.
• A dream workspace: A sunny office with stunning views over Leuven, park walks, and coffee by the Vaartkom.
• A vibrant culture: Regular after-works, sports sessions, hackathons, and company retreats.
• Uncapped growth: The opportunity to grow into broader roles as the company — and you — scale.