Senior .NET Backend Engineer

Next Learning Valley; Utrecht; Hybrid; EUR 70,000 - 100,000; Full time

Job summary

Next Learning Valley is seeking a hands-on Senior .NET Backend Engineer to design, build and operate robust backend services and modular applications. You will focus on production-ready APIs, background services and clean architecture with strong ownership.

You’ll design APIs, work with Postgres, Docker, CI/CD, and cloud services like Azure, while collaborating across backend, frontend and platform teams to deliver scalable solutions.

Qualifications

• Proficient in C# with experience building production APIs.
• Solid REST and OpenAPI design and implementation experience.
• Hands-on with Docker, Git and CI/CD pipelines; microservice/multimodule architectures.

Responsibilities

• Design, build and maintain APIs using .NET and ASP.NET Core.
• Develop clean, maintainable C# code and apply async patterns.
• Design REST and OpenAPI contracts and support modular architectures.
• Troubleshoot production issues and ensure secure, production-ready solutions.
• Design PostgreSQL schemas and migrations; optimize SQL performance.
• Work with Kafka or Azure Service Bus for integrations; support CDC/streaming.

Skills

Advanced C#

REST & OpenAPI

Microservices

Modular Monolith

Git

CI/CD

Strong analytical skills

Tools

Docker

Azure Service Bus

Kafka

Prometheus

Grafana

Job description

We are looking for a hands-on Senior .NET Backend Engineer to help design, build and operate robust backend services and modular applications within our broader platform environment.

This role is focused on developing production-ready APIs, background services and backend components with a strong emphasis on clean architecture, maintainability, reliability and technical ownership.

Key Responsibilities

• Design, build and maintain APIs using .NET and ASP.NET Core
• Develop clean and maintainable C# code
• Apply async/await, dependency injection and minimal APIs
• Design REST and OpenAPI contracts
• Support modular monolith and microservice architectures
• Troubleshoot production issues
• Ensure secure and production-ready solutions
• Design PostgreSQL schemas and migrations
• Optimize SQL performance
• Design REST and event-driven integrations
• Work with Kafka or Azure Service Bus
• Support CDC and streaming integrations

Cloud, Containers & Platform Operations

• Containerize services with Docker
• Deploy through CI/CD pipelines
• Work with Azure platform services
• Use observability tooling such as Prometheus and Grafana
• Apply Infrastructure as Code

Security, Collaboration & Technical Ownership

• Work with OAuth2, JWT and Keycloak
• Collaborate with backend, frontend and platform teams
• Review pull requests
• Take ownership of technical solutions
• Support GDPR and compliance requirements

Required Experience

• Advanced C#
• REST & OpenAPI
• Docker
• Git & CI/CD
• Microservices / Modular Monolith
• Strong analytical skills

Strongly Desired

• Keycloak

Nice to Have

• Python
• Change Data Capture (CDC)
• Data Platforms
• GDPR / Regulated environments
• React or TypeScript

This profile is intended for a senior hands-on backend engineer who contributes to both implementation and solution-level technical decisions.

Who We Are

Next Learning Valley is the leading implementation partner for innovative learning technologies in the Netherlands and Belgium. As the exclusive partner of Learning Pool, we work with Stream LXP, Learning Locker (LRS), and Learning Pool Automation to help organizations create modern, data-driven learning ecosystems.

In addition, we develop our own solutions that enable organizations to deliver more personalized, intelligent, and data-driven learning experiences. Our platforms and technologies provide the foundation for future-ready learning and development.

If you see yourself in this role, we’d love to hear from you.