Experienced Software Developer – Team Box Collab

Dalux; Københavns Kommune; On-site; DKK 850,000 - 1,150,000; Full time

Benefits offered by this job

In-house development

Career growth

AI-focused engineering

Job summary

Dalux is seeking an experienced software developer to join the Box Collab team in Copenhagen. You will own complex features from idea to production, collaborate with Product Managers and Designers, and help evolve the technical foundations of the Box Collab product.

You will contribute to architectural decisions, improve existing codebases, and drive AI-assisted development practices across the team. A strong fundamentals focus with hands-on leadership is essential.

Qualifications

• Strong C# and .NET experience with a proven track record.
• Deep DB experience including indexing strategies and query performance optimization.
• Experience modernizing established software systems and shaping architecture.
• Understanding of Domain-Driven Design or modular architectures for complex apps.
• Experience mentoring other developers and providing technical sparring.
• Practical experience with AI-assisted development tools and workflows.

Responsibilities

• Own complex features and technical problems end-to-end.
• Design and implement scalable, maintainable solutions.
• Contribute to architectural decisions and technical direction of Box Collab.
• Improve code structure and reduce technical debt in an established codebase.
• Collaborate with Product Management and Design to deliver value.

Skills

C# & .NET

DB management

Software modernization

Domain-Driven Design

Mentoring/technical sparring

AI-assisted development

Job description

Build software at scale. Influence how we build it. Help modernize a product area at the heart of construction projects.

Dalux is growing, and we are looking for an experienced software developer to join our Box Collab team.

You will build software in our File Management product (Box) that enables communication and collaboration across construction stakeholders—for example, file comments, sharing, versioning, and review. This domain is widely used and deeply integrated across the Dalux product suite, so reliability, performance, and strong technical design are essential. In Box Collab, we foster an engaging, enjoyable work environment where people take ownership and accountability for outcomes. You’ll join a young, skilled team with strong opportunities to influence both product evolution and architectural direction.

Your role

As an Experienced Software Developer, you will take ownership of complex product and technical problems from idea to production.

You will join a full-stack development team working closely with a Product Manager and Product Designer. We expect experienced developers to contribute beyond their individual tasks: helping make good technical decisions, improving the codebase and architecture, sharing knowledge, and raising the engineering standard around them.

Within Box Collab, there is a particular focus on strengthening and evolving the technical foundation of the product while continuing to deliver new functionality.

Your work can include:

• Owning complex features and technical problems end-to-end
• Designing and implementing scalable, maintainable solutions
• Contributing to architectural decisions and the technical direction of Box Collab.
• Improving the structure of an established codebase and reducing technical debt
• Helping evolve boundaries and modularity within the application
• Sparring with and mentoring other developers
• Working closely with Product Management and Design to understand problems and find the right solutions
• Bringing new ideas, technologies, and development practices into the team when they create real value

We expect experienced developers to have opinions, challenge existing solutions, and be comfortable having their own ideas challenged in return.

AI-assisted software development

We are significantly increasing our focus on AI-assisted development across Dalux.

We are actively exploring how AI can improve the software development lifecycle – from understanding requirements and exploring technical approaches to coding, testing, review, debugging, refactoring, and automation.

The Box Collab team is already experimenting with how these tools can improve its day-to-day development work.

As an experienced developer, we want you to take an active role in that development: experimenting with new workflows, critically evaluating their value, sharing what works, and helping establish good engineering practices around AI-assisted development.

Practical experience using AI as part of your development workflow is an advantage. More importantly, you should be curious about how these tools are changing software engineering and willing to continue evolving your own way of working.

Technologies we work with

Box Collab is a full-stack product area primarily built with:

• C# / .NET
• Angular / TypeScript
• MSSQL
• Elasticsearch

Our wider platform runs on a distributed cloud architecture using AWS.

Experience with our exact technology stack is useful, but strong software engineering fundamentals and the ability to understand and improve complex systems matter more.

What would make you a particularly strong match?

We are looking for an experienced software developer with strong technical fundamentals and the ability to influence the software around you.

For this particular team, we would especially value:

• Str ong professional experience with C# and .NET
• Strong DB management experience, including indexing strategies and query performance optimization.
• Experience improving or modernizing established software systems
• An understanding of Domain-Driven Design, modular architecture, or similar approaches to structuring complex applications
• Experience mentoring or providing technical sparring to other developers
• Practical experience with AI-assisted development tools and workflows

You do not need to match every point.

Technical judgment, curiosity, and the ability to make an established product better are more important than having worked with exactly the same technologies or architectural patterns before.

Product development at Dalux

Our product teams bring developers, Product Managers, and Product Designers together.

Developers are expected to understand the problem being solved and contribute to finding the solution – not simply implement specifications handed to them.

As an experienced developer, you will have an important voice in balancing user value, usability, technical feasibility, business viability, and long-term technical health.

Our products are relied upon by professionals worldwide, making performance, stability, maintainability, and quality important parts of everyday engineering.

What You Can Expect From Dalux

Dalux is a software company at heart.

As an experienced developer, you can expect:

• Significant ownership of the software you build
• Real influence on technical solutions and engineering practices
• Skilled colleagues who enjoy technical discussion and constructive challenge
• Close collaboration between Engineering, Product Management, and Design
• Short paths from technical ideas to decisions and implementation
• Opportunities to improve an established product and architecture
• A healthy work-life balance, with a strong focus on a sustainable work week and no overwork culture.
• Clear opportunities for professional and career growth.
• An environment actively investing in AI-assisted software development
• High levels of trust and freedom in how you solve problems
• A social workplace with monthly events and employee-driven clubs

All Dalux software development takes place in-house at our headquarters in Vibenshuset, Copenhagen. Working together in person is an important part of how we collaborate, share knowledge, and make decisions quickly.

About Dalux

Dalux is a Danish software company founded in 2005 by Bent Dalgaard and Torben Dalgaard.

We build digital tools that make the construction industry smarter and more efficient. Using our own 3D BIM technology, Dalux develops user-friendly software used in more than 140 countries worldwide.

Our core technology is developed entirely in-house, giving our developers the opportunity to influence both the products and the technology behind them.

Interested?

If you are looking for a role where you can remain hands-on while gaining greater technical influence and helping evolve an established product and architecture, we would like to hear from you.

We recruit continuously as Dalux grows.

Application deadline

Ongoing