.NET/C# Backend Developer

Backend Development - B2B Platform

• Design, develop, and maintain .NET/C# backend services, APIs, and integrations that power Eneco's B2B digital platform
• Build and maintain the integration layer between frontend and backend systems, ensuring reliability, performance, and maintainability
• Contribute to the full software development lifecycle - from solution design and implementation through to testing, deployment, and operational support
• Collaborate closely with frontend engineers, product managers, testers, and designers to deliver business features end to end
• Identify and resolve performance, reliability, and maintainability issues proactively

Backend Architecture - Community of Practice

• Participate actively in Eneco's Backend Community of Practice - a cross-organisational group of backend engineers working together to optimise the backend ecosystem
• Contribute to architectural discussions about backend standards, patterns, and tooling across the organisation
• Support knowledge sharing, code reviews, and technical best practices to raise engineering quality across teams
• Help evaluate and validate technical solutions through Proof of Concepts in collaboration with architects and senior stakeholders

Engineering Quality and Ownership

• Write clean, testable, and maintainable code that meets both business and technical requirements
• Take ownership of assigned work - communicate progress, flag blockers early, and deliver reliably
• Contribute to documentation and continuous improvement initiatives within the team
• Expand your skills beyond your core stack when the team needs it - you bring a T-shaped mindset

Purpose of the Role

Eneco's B2B platform connects businesses to smarter, more sustainable energy choices. Behind every digital interaction - every integration, every API call, every data flow - is backend infrastructure that needs to be reliable, scalable, and clean. That is where you come in.

You will be the backend engineer embedded in Eneco's B2B product team, building and maintaining the .NET platform that sits between frontend and backend systems. Most of your time goes into delivering business features alongside product managers, frontend engineers, testers, and designers. The rest goes into something rarer - a cross-organisational Backend Community of Practice where backend engineers from across Eneco collaborate to keep the organisational backend ecosystem healthy, consistent, and future-proof.

This is not a role where you code in a silo. You will shape backend decisions that matter beyond your own team.

You are a backend engineer who takes pride in writing code that other engineers enjoy working with. You have 3-5 years of experience with .NET/C# and you know your way around a production environment - you have built APIs, debugged integrations, and cared about what happens after deployment. You are not just a feature builder. You care about the bigger picture - how systems connect, how decisions made today affect the platform in two years, and how to push back constructively when a shortcut creates long-term debt. If the idea of shaping backend standards across an entire organisation - not just within your own team - sounds interesting rather than abstract, this role was written for you.

Experience

• Hands-on backend development experience with .NET/C#
• Experience building and maintaining APIs, backend services, and integrations in a production environment
• Familiarity with cloud platforms, particularly Azure
• Experience with relational databases, specifically SQL Server - designing and optimising data access solutions
• Experience with containerised applications (Docker) and modern architectures such as microservices and event-driven systems
• Comfortable working in CI/CD pipelines and contributing to DevOps practices

Knowledge and Expertise

• Solid understanding of software design principles, clean code practices, and what makes code maintainable and testable
• Familiarity with integration patterns between frontend and backend systems
• Understanding of scalable and performant backend architecture
• Experience in or appetite for cross-team technical collaboration and architectural discussions
• Exposure to the energy sector, B2B digital platforms, or large-scale enterprise environments is a plus - not a requirement

Skills and Competencies

• Collaborative by nature - you work well with frontend engineers, product managers, testers, and designers
• Clear communicator who can contribute to architectural discussions and articulate technical trade-offs
• Ownership mindset - you take responsibility for your work from design through to production
• T-shaped: strong backend depth with the flexibility to support the team across disciplines when needed
• Curious and learning-oriented - you look for ways to improve systems and share what you learn

You will join Eneco's Tech department as part of the B2B product team - a cross-functional group of frontend engineers, backend engineers, product managers, testers, and designers focused on building digital solutions for Eneco's business customers. Around 80-90% of your time is spent here, delivering features end to end.

The other 10-20% of your time goes into Eneco's Backend Community of Practice - a vertical team of backend engineers from across the organisation who come together regularly to align on standards, review architectural decisions, and keep the organisational backend ecosystem in good shape. This gives you a wider view than most backend roles offer - you are not just building for one team, you are helping shape how Eneco builds backends at scale.

You will work hybrid - focus days at home combined with collaboration days at Eneco's Rotterdam HQ.

Please apply directly via the Eneco Careers Portal. Applications submitted by email will not be processed.

Third Party Disclaimer

Eneco manages recruitment through selected channels and preferred partners. Unsolicited acquisition, candidate submissions, or commercial outreach in relation to this vacancy are not appreciated.

• Backend work with two layers of impact

  Most backend roles live inside one team, one product, one domain. Here you contribute to the B2B platform day to day and to Eneco's organisational backend ecosystem through the Community of Practice. Your architectural input reaches further than your own codebase.

• A team that ships and cares about quality

  You will work with a full cross-functional B2B team - product, design, frontend, testing - that is focused on delivery. And you will work with backend engineers across Eneco who care enough about quality to meet regularly and hold each other accountable to high standards.

• Engineering that connects to something real

  Eneco's B2B platform helps businesses make smarter, more sustainable energy choices. The integrations and APIs you build directly enable that. By 2035, Eneco aims to be climate neutral - your platform is part of how that happens.