.NET Developer

About Assai

Assai brings clarity and control to the world’s most complex engineering environments.

Our AI-powered data platform helps global leaders in energy, utilities, petrochemicals, renewables, and other asset-intensive industries manage their engineering information with structure, accuracy, and confidence. By connecting documents, data, and workflows across the full asset lifecycle, from design and construction to operation and decommissioning Assai provides a single, reliable source of truth.

For more than 30 years, organizations have relied on Assai to deliver projects and operations that are predictable, compliant, and audit ready. Whether for a single capital project or an enterprise-wide portfolio, our platform enables teams to make informed decisions, reduce risk, and deliver better outcomes.

Our people make this possible. Working from offices around the world, we share a commitment to precision, quality, and meaningful innovation, creating technology that supports the industries that keep the world running.

At Assai, technology and engineering come together with purpose, to make complex work clear, controlled, and connected.

The Role

We are looking for a .NET Developer (Mid-Sr. Level) to strengthen our development team in Culemborg. As part of a cross-functional Agile team, you will contribute to the development and enhancement of our cloud-based platform. You’ll write clean, maintainable code, collaborate with team members, and have the opportunity to grow your technical skill set through exposure to modern architectures and tools.

Key Responsibilities

Design, develop, and maintain back-end components using .NET and C#.

Collaborate with product owners, testers, and other developers to deliver high-quality features.

Implement business logic, RESTful APIs, and integrations with external systems.

Participate in daily stand-ups, sprint planning, and code reviews.

Contribute to continuous improvement of development practices and product architecture.

Troubleshoot and debug application issues in development and production.

Working Conditions

Assai Software Services offers a diverse and flexible job in a growing international organization with good future perspectives. At work, we have an informal culture with a team spirit and hands-on environment, where good employment conditions apply. Assai is an innovative organization where you have the opportunity to shape your own tasks and responsibilities, taking the organization's objectives into account. The job takes place in our Dutch office, and we are looking for a full-time employee (40 hours).

Additional Information

• A collaborative, technically driven team environment
• Competitive salary and secondary benefits
• Opportunities for professional development and training
• Hybrid work policy (office in Culemborg + Office in Amsterdam + flexible remote days)
• Impactful work on a product used by global industry leaders

Our Values

We foster empowerment and like to stimulate a ‘ can do’ mentality by also being supportive of each other and our customers. By closely working together, we are continuously looking for improvements , which will support our effectiveness in our roles.

5 years of experience in .NET development (.NET Core, .NET Framework, ASP.NET Core).

Good understanding of object-oriented programming, software design principles, and clean code practices.

Experience working with REST APIs, Entity Framework Core, Docker, Git and PostgreSQL.

Basic familiarity with front-end technologies (HTML / CSS / JavaScript / React) is a plus.

Experience with NHibernate, Dapper, unit / integration testing, SAML, GitHub Actions, Kubernetes, Helm Charts, Terraform, Open API, Open Telemetry, IIS is a plus.

Exposure to Agile development methodologies (Scrum preferred).

Understanding of version control (Git), unit testing, and CI / CD tools.

Bachelor’s degree in Computer Science, Software Engineering, or related discipline.

Willingness to learn, take initiative, and work collaboratively in a team setting.