Junior Backend Developer (High-Performance E-Commerce Platform, On-Site in Haarlem)
About the Role
We are looking for a Junior Backend Developer to join our team on-site in Haarlem.
This is an opportunity for a motivated recent graduate (or soon-to-graduate student) in Software Development, Computer Science, or a comparable field (HBO or equivalent) to start your professional career in a high-performance, high-impact environment .
You will contribute to the development of our next-generation e-commerce platform as we transition from a fully custom system to Commercetools . You will be part of a senior-led team that builds scalable, high-quality backend services using .NET Core 8 , Azure , microservices architecture , CQRS , and Domain-Driven Design (DDD) principles.
We expect you to bring strong technical fundamentals, a proactive mindset, and a willingness to learn rapidly from experienced professionals.
Responsibilities
Develop and maintain backend services in C# and .NET Core 8 within a microservices environment.
Assist in migrating functionality from legacy systems to Commercetools, implementing standard and custom functionality.
Work with RabbitMQ and other messaging solutions to build reliable asynchronous communication between services.
Write SQL queries and manage data in Microsoft SQL Server.
Support the development and maintenance of CI/CD pipelines using Azure DevOps.
Collaborate with senior developers to extend Commercetools where needed for complex business requirements like logistics, payments, invoicing, and recurring orders.
Contribute to code reviews, testing, and documentation , maintaining high standards of code quality and reliability.
Continuously learn and apply best practices in backend development, cloud services, and scalable system architecture.
Requirements
Recent graduate (or about to graduate) with an HBO degree in Software Engineering, Computer Science, or a related field.
Solid foundation in C# and .NET Core development , including understanding of object-oriented programming and basic design patterns.
Basic knowledge of relational databases and SQL , preferably with SQL Server.
Interest in cloud platforms , ideally with some exposure to Azure (e.g., through internships, school projects, or self-study).
Understanding of basic backend architecture concepts , such as REST APIs, microservices, messaging, and event-driven systems.
Strong communication skills , with the ability to work effectively within a team and ask the right questions when needed.
Eagerness to learn advanced concepts like CQRS, DDD, CI/CD pipelines, and scalable e-commerce system design.
Proactive and disciplined work ethic : you take ownership of your learning curve and delivery tasks.
Nice to Have
Internship or project experience with .NET Core, Azure, RabbitMQ, or SQL Server.
Exposure to e-commerce systems (order management, logistics, payment processing).
Familiarity with Commercetools or other headless commerce platforms.
Experience working with Git, DevOps tools, or Agile/Scrum environments.