As we're planning to install 3.000.000 heat pumps by around 2030 we're seeking a highly motivated and ambitious person that's not afraid to make her or his hands dirty and make a real dent in the climate change challenge that we are already facing. Are you ready to rise to the challenge?

As Senior Full-Stack Engineer you will join our Software & Infrastructure team. You will work closely with our other engineering teams, which build the hardware, embedded software and controller for our heat pumps and home batteries, designing and implementing features across the entire stack. Our product family spans hybrid and all-electric heat pumps, cooling, and home batteries — and our platform orchestrates all of it: built in Node.js/TypeScript (Express), backed by MySQL, Redis and ClickHouse for time-series telemetry, with OpenAPI-specified REST APIs. On top of that we build the internal & support dashboards in React and our customer/installer app in React Native — all in TypeScript, end to end. Our fleet of tens of thousands of devices connects over MQTT, streaming stats continuously — so you'll be working on a real-time IoT pipeline at scale, not just a CRUD backend.

This is a backend-focused role: roughly 80% of your work is on the backend, telemetry pipeline and cloud platform, with the remaining ~20% spanning our React dashboards and, occasionally, the React Native app. We're looking for backend depth first, with the comfort to work across the full stack when a feature calls for it.

🌱 What you'll be doing:

• Build and evolve the backend behind our customer app, installer tools and internal dashboards — from device commissioning flows to energy insights and smart-control features.

• Work on our telemetry pipeline: ingesting, processing and querying second-level data from tens of thousands of heating systems and batteries (AWS IoT Core, SQS, ClickHouse, BullMQ).

• Build the energy side of our platform: home-battery charging strategies, dynamic energy tariffs, and integrations with energy-market and EMS systems.

• Design APIs (OpenAPI) and integrate with third-party platforms such as HubSpot and field-service systems.

• Help architect our cloud infrastructure as the fleet grows — performance, scalability, observability and cost.

• Build and own our internal and support dashboards (React) — the tools our support and operations teams rely on to manage the fleet and help customers.

• Contribute to our customer and installer app (React Native) where product work spans the full stack.

• Collaborate with cross-functional teams (app, embedded, hardware, data) to ship new features across the Netherlands.

• Troubleshoot and resolve production issues across the pipeline, from device message to API response.

• Own the health of the platform: alongside new features, you'll pick up maintenance work dependency upgrades, refactoring, fixing legacy corners, and improving reliability. We're a scaleup: we do what needs doing, and everyone owns the boring-but-critical work too.

• Together with the team, brainstorm ideas on how to improve our internal processes and help us grow.

💡 What you'll need?

• You want to make a positive impact on the world and fight climate change.

• 5+ years of engineering experience, with strong TypeScript across the stack and depth on the backend (Node.js) — or the seniority to get there fast — and a Bachelor's degree in Computer Science or Engineering.

• Comfortable building UIs in React; React Native experience is a plus, not a requirement.

• Solid experience with relational databases and data modeling (we use MySQL with Prisma); experience with time-series or analytical databases like ClickHouse is a plus.

• You've built event-driven systems: message queues, background workers, or streaming pipelines (we use MQTT, AWS SQS, BullMQ and Kafka).

• Comfortable with cloud infrastructure (we run on AWS) and you think about performance, scalability and cost as the fleet grows.

• We are an AI-driven engineering team: AI agents write most of our code, and engineers direct, review and own the result. You should be excited to work this way — your value is in system design, judgment and quality control, not in typing speed.

• You take ownership beyond the merge: you write thorough tests, monitor what you ship, and can debug a production issue from device message to API response.

  Experience with IoT, embedded systems or the energy domain is a plus — not a requirement.

• You do not require visa sponsorship to live and work in the Netherlands.

🤷‍♀️ Why Quatt?

• An opportunity to be a part of a fast-growing, ambitious scaleup on the mission to fight climate change.

• Personal development, freedom, and career growth opportunities.

• An open organizational culture, where you can hang out and discuss ideas with everyone, from installer to founder.

• Flexibility to work hybrid, which means 3 days in the office and 2 days from home.

• 25 paid holiday leave days + 8% holiday allowance

• Free vegan/vegetarian lunch in the office daily 🥗

• Travel compensation of €0,23/km or an NS-business card 🚆

• Access to mental health platform OpenUp

• Informal culture with monthly drinks and office parties 🍻

• Yearly discount on Quatt-products

• Referral bonus of up to €2.000 when referring new colleagues

• Work in an international team with people from over 30 nationalities. 🌐