Senior Backend Engineer .NET (Quality Engineering)

Eneco; Rotterdam; On-site; EUR 90,000 - 120,000; Full time

Job summary

Eneco's engineering team builds the platforms behind our Virtual Power Plant. You will develop .NET/C# backend services that connect large batteries, rooftop solar and customer assets to Eneco's VPP, enabling market participation.

We emphasize automated testing, load testing, AI-assisted development, and on-call reliability, with opportunities to mentor others and influence system design.

Qualifications

• Around 7 years of backend experience in .NET/C#.
• Experience with event-driven architecture and async messaging (e.g., Kafka, RabbitMQ).
• Comfort with Azure, CI/CD, Docker/Kubernetes, microservices, and both relational and non-relational data.
• Strong Quality Engineering mindset: quality, testability and automation are part of building software.
• Experience with automated integration and E2E testing.
• Load and performance testing experience and ability to investigate bottlenecks.

Responsibilities

• Build and maintain .NET/C# backend services connecting assets to Eneco's VPP.
• Design and maintain automated integration and end-to-end tests and run load tests for 24/7 operations.
• Drive AI-assisted development and contribute to system design with architects.

Skills

.NET/C# backend development

Event-driven architecture

Azure cloud

Docker/Kubernetes

CI/CD

Testing & QA mindset

AI-assisted development

On-call experience

Tools

Kafka

Azure Event Hubs

RabbitMQ

Docker

Kubernetes

Job description

At Eneco we work towards one clear goal: being climate-neutral by 2035. A big part of that is flexibility, using renewable energy at the right moment. Our Virtual Power Plant (VPP) links many energy sources and steers them centrally as one portfolio.

More and more of that flexibility sits "behind the meter", at our customers' sites: large batteries, solar panels and other installations. Your services make it possible for these smaller assets to join the market together. That means more green energy used well, and less need for fossil backup. You do this in a team that takes engineering seriously, shares what it learns, and gives you room to grow as a technical leader.

• You build and maintain backend services and integrations in .NET/C#.
• You develop solutions that optimise behind-the-meter assets and connect data flows so smaller assets can trade as part of Eneco's pool.
• You design and maintain automated integration and end-to-end tests, so the team can trust every release of our services and integrations.
• You run load and performance tests to find bottlenecks, scalability risks and reliability issues before they reach production.
• You keep improving test automation, test coverage and feedback cycles, so developers know quickly when something breaks.
• You build quality into features from the start, instead of testing them afterwards.
• You use AI tools across your work, including test generation, refactoring and debugging, and review the output critically.
• You drive Proofs of Concept and work with architects on system design.
• You mentor medior and junior engineers through code reviews and technical guidance.
• You share on-call duty for a system that runs 24/7.

• Reliable, scalable services that connect distributed assets to our VPP and keep running 24/7.
• Quality built into the development lifecycle through automated testing.
• New features and services that ship with the right integration and E2E test coverage.
• Performance and scalability, backed by load and performance testing.
• Faster, more reliable feedback for the team through more automation.
• Technical ownership of your components, including tackling technical debt and reliability risks early.
• AI-assisted work that meets the same bar for security, quality and maintainability as anything else.
• A stronger team through reviews, mentoring and shared standards.

• You have around 7 years of backend experience in .NET/C# and have built complex, high-availability distributed systems.
• You know event-driven architecture and async messaging, for example Kafka, Azure Event Hubs or RabbitMQ.
• You're comfortable with Azure, CI/CD, Docker/Kubernetes, microservices, and both relational and non-relational data.
• You have a strong Quality Engineering mindset: to you, quality, testability and automation are part of building software.
• You have practical experience with automated integration and E2E testing.
• You've done load and performance testing and know how to investigate performance and scalability risks.
• You're a software engineer first. You enjoy building features and the tests that prove they work, rather than focusing on test automation alone.
• You use AI-assisted development tools in your daily work, check their output critically, and like sharing what works with your team.
• You're happy to take on-call responsibility, live in the Netherlands and speak English fluently.
• Knowledge of energy markets, optimisation or aggregation platforms is a plus. Don't have it yet? You'll learn the domain here.
• Recognise yourself in most of this, but not every requirement? We'd still love to hear from you.

You join an engineering team working on the platforms behind our Virtual Power Plant. You work closely with fellow engineers, architects and colleagues from other disciplines. We review each other's code, share what we learn, and explore AI and automation together, so you get plenty of room to bring in your own ideas.

• You build .NET/C# services that connect large batteries, rooftop solar and other customer-side assets to our Virtual Power Plant.
• You make quality part of how features get built: automated integration and E2E tests, plus load and performance testing for a system that runs 24/7 in live energy markets.
• You help the team work smarter with AI-assisted development, from test generation to debugging.