Senior Software Engineer (Typescript/Next.js) (m/f/d)

About Us

At LeasingMarkt.de, we bring customers and dealers together to make car leasing more accessible, transparent, and efficient. With over 1,000 partner dealerships and nearly 2 million users across the DACH region and the Netherlands, we've become Germany’s #1 leasing platform. To keep growing and driving innovation in the mobility space, we’re looking for a Lead Software Engineer to join our high-performance team at our Düsseldorf office.

As a Senior Software Engineer, you will play a key role in designing and developing robust, scalable web applications that power one of the largest automotive leasing marketplaces in Europe. You'll collaborate with a cross-functional team to build and improve solutions that are not only effective, but also architecturally sound and easy to maintain. You'll help us elevate the standard for software quality, stability, and long-term value.

What You’ll Do:

• Improve and extend our existing codebase while maintaining a high standard of code quality and test coverage.

• Design and implement scalable, maintainable, and well-structured solutions based on modern architecture principles.

• Drive architectural decisions with a focus on modularity, clean code, and long-term maintainability.

• Work in an agile, cross-functional team, contributing your ideas and pushing for continuous improvement.

• Set high quality gates for new modules, emphasizing testability and performance.

• Support and mentor other team members.

What You Bring:

• Strong experience with TypeScript and modern React / Next.js

• Ensure accessibility, responsiveness, and cross-browser compatibility.

• Experience with server-side rendering (SSR), static site generation (SSG), and API routes in Next.js.

• Solid understanding of performance optimization, caching, and CDN strategies.

• Solid understanding of component-based architecture, state management, and modern web APIs

• Deep knowledge of software design principles (e.g., SOLID, DRY, KISS)

• Passion for clean, testable, and maintainable code

• Familiarity with CI/CD pipelines, Git, and agile development practices

• A collaborative mindset and willingness to share knowledge and best practices

• Experience with or openness to PHP (Laravel) is a big plus

• Experience with cloud platforms (especially AWS) and containerization (Docker/Kubernetes) is a plus

• Experience with Tailwind CSS is a plus.

• Experience leveraging AI, Generative AI (GenAI) to enhance engineering productivity, automate repetitive tasks, and optimize workflows. You should demonstrate the ability to integrate AI-driven solutions into your daily work — such as code generation, debugging, reviews, documentation, and decision support—to improve efficiency for yourself and your teams. A proactive approach to exploring and implementing AI tools that drive innovation and streamline development processes is highly valued.

What we offer

When it comes to benefits, we focus on full flexibility: as your life changes, your professional and private preferences may shift as well:

• An experienced, friendly team with flat hierarchies and open communication

• Two days of remote work per week and flexible working hours

• 30 days of vacation + Christmas and New Year's Eve off

• Option for “workation”

• Modern office in the heart of Düsseldorf

• Muesli, fruit, and drinks included, including a portafilter machine

• Games corner (PlayStation, Switch, table tennis...)

• Company pension plan, job bike, corporate benefits, and much more