Full Stack Engineer, Frontend-focused (Next.js + Django)

DeWarmte; Den Haag; On-site; EUR 47,000 - 71,000; Full time

Benefits offered by this job

Gross salary (monthly)

27 vacation days

8% holiday allowance

SAR programme

Lunch at the office

Laptop provided

AI tooling access

Team events

Job summary

DeWarmte is hiring a frontend-focused Full Stack Developer to enhance our web app for heat-pump customers from discovery to installation.

You will work primarily in TypeScript frontend (Next.js, React 18) with Django backend touches. Build clear, fast, accessible interfaces and influence conversion and customer satisfaction while collaborating across marketing, sales, installation and service teams.

Qualifications

• Strong hands-on experience building production web apps with frontend depth.
• Expertise in TypeScript/React and Next.js; Pages Router knowledge is a plus.
• Solid HTML/CSS fundamentals with responsive, accessible UI.
• Experience shipping customer-facing flows: onboarding, quotes, checkout or self-service portals.
• Ability to take functionality from design through implementation, testing and deployment.
• Comfortable with REST APIs and making focused changes in Python/Django.
• Knowledge of web performance, SEO, automated testing, CI/CD and observability.
• Uses AI coding tools and understands their value and limits.

Responsibilities

• Build, test and deploy customer-facing features in Next.js and React with Django/API changes as needed.
• Turn customer needs into clear, responsive interfaces and flows from interest to installation.
• Improve conversion, speed and usability based on data and feedback.
• Connect frontend with workflows used by sales, planning, installation and service teams.
• Improve frontend architecture, reusable components, testing, CI/CD and observability.
• Collaborate with Backend Developer to shape APIs and document engineering practices.
• Review code and share knowledge by default.

Skills

TypeScript

React

Next.js

HTML/CSS

REST APIs

Django

AI tooling

UI/UX

Tools

Next.js

Django

REST API design

Job description

At DeWarmte, we make smart, affordable heat pumps that help homes move away from gas. We design the hardware, software and services ourselves, so the quality of our software directly shapes how well our products work in people's homes.

We're growing fast, and the customer journey is growing with us. That's why we're looking for a frontend-focused Full Stack Developer to improve our web application - from the first visit and heat-pump advice to quotation, planning and installation. You'll spend most of your time in Next.js and React, making every interaction clear, fast and genuinely pleasant.

You'll work primarily in our TypeScript frontend (Next.js Pages Router, React 18), with focused changes to our Django backend when a feature needs them. You'll take customer-facing work from idea to production and see directly what it does for conversion, customer satisfaction and the workload of our teams.

AI tools are already part of how we build software. We use them where they help us move faster, but we do not lower the bar: anything we ship still needs to be secure, maintainable and correct. You'll help us get better at both.

Why this role matters

Make switching to a heat pump simple, clear and trustworthy - from first discovery to installation and beyond.

You'll join the team behind a web application that our customers use every day. You'll get to know it deeply, keep it reliable and improve it as we grow. Just as important: you'll help make sure knowledge and ownership are shared across the team.

What you'll do

Build a great customer experience

• Build, test and deploy customer-facing features in Next.js and React, with supporting Django and API changes where needed.
• Turn customer needs and designs into clear, responsive and accessible interfaces.
• Build the flows that guide customers from first interest to advice, quote, order, planning and installation.
• Keep improving conversion, speed and usability based on data and customer feedback.

Support customers after installation

• Improve the flows customers use after installation, from questions and service requests to documents and updates.
• Connect the web application with the workflows used by our sales, planning, installation and service teams.
• Remove manual work and friction for customers and colleagues alike.

Strengthen the frontend platform

• Improve frontend architecture, reusable components, performance, accessibility and SEO.
• Improve automated frontend testing, CI/CD, monitoring and safe release practices.
• Work with the Backend Developer to shape clear APIs and interfaces between the web application, apps and external systems.
• Turn implicit knowledge into clear documentation and repeatable engineering practices.
• Review code and share knowledge by default.

Build with AI

• Use AI tools to support design, coding, testing, reviews and documentation.
• Help the team improve its AI workflows, shared context and quality checks.
• Try new tools, keep what works and share what you learn.
• Hold AI-assisted code to the same standards as any other production code.

Work across the company

This role reaches beyond the software team. You'll work with marketing, sales, planning, installation, service and product development to solve today's customer and operational issues without compromising the platform for tomorrow.

What success looks like

In your first few months

• You understand the customer journey end to end, the frontend architecture and where it connects to our backend.
• You can independently ship frontend features and make focused Django or API changes when needed, using the team's review and release practices.
• You've identified the biggest usability issues and frontend technical risks in the journey, and helped prioritise them.

As the role develops

• New frontend features ship predictably, safely and with good test coverage.
• More visitors become customers, and customers rarely need to contact us to know where they stand.
• You take responsibility for the frontend architecture and significant parts of the customer journey.
• The team uses AI tools confidently and responsibly in its day-to-day work.
• Critical parts of the frontend are understood and maintained by more than one person.

Who we're looking for

• Solid hands-on experience building and shipping production web applications, with most of your depth on the frontend.
• Strong TypeScript and React skills, plus experience with Next.js; familiarity with the Pages Router is useful.
• Strong HTML and CSS fundamentals, with a good eye for responsive design, accessibility and interaction details.
• Experience building customer-facing flows such as onboarding, configurators, quotes, checkout or self-service portals.
• A track record of taking functionality from design through implementation, testing and deployment to real-world use.
• Comfortable working with REST APIs and making focused changes in Python/Django; deep backend specialisation is not required.
• A good understanding of web performance, SEO, automated testing, CI/CD and observability.
• You use AI coding tools in practice and understand both their value and their limits.
• A feel for user experience and a knack for making complex information simple.

Experience with design systems, analytics or experimentation, e-commerce, CRM or planning integrations, or the energy or installation sector is useful, but not essential. What matters most is that you care about the customer experience and can take frontend work from idea to production.

How you work

• You fix urgent problems without letting short-term workarounds become long-term architecture.
• You think from the customer's perspective and judge your work by what it does for them.
• You're comfortable moving between interaction details, frontend architecture and the API contract behind them.
• You're curious about new AI tools, try them quickly and share what works.
• You explain technical topics clearly to people from any background.
• You share knowledge by default and care about what the team can own together.

What we offer

• A role with direct impact on the customer journey that helps homeowners move away from gas.
• A clear frontend focus, with enough Django scope to take features end to end.
• Room to improve how we use AI tools across the software team.
• A gross monthly salary of [€X.XXX - €X.XXX], based on full-time employment.
• 27 vacation days and 8% holiday allowance.
• The chance to share in DeWarmte's growth through our Stock Appreciation Rights (SAR) programme.
• An ambitious, collaborative team and real responsibility from day one.
• Daily lunch at the office.
• A laptop, access to the AI tools we use and everything else you need to do your best work.
• Regular team activities, including our annual Beach Day and Winter Trip.
• Plenty of room to grow, develop yourself and make a lasting impact.