Senior C# Engineer

Senior C# Backend Developer

SaaS | Industrial IoT | AI-Augmented Engineering

We are looking for a highly experienced C# developer to play a key role in our topology development team.

Secomea, headquartered in Nordhavn (Copenhagen), builds secure Industrial IoT solutions used globally. With offices in China, Japan, and North America and a strong international partner network, we are on a mission to raise the bar for secure, scalable, and easy-to-use remote access solutions for industrial environments.

The Role

You will take a senior technical role in an experienced backend team responsible for core parts of our SaaS platform. We expect strong architectural thinking, ownership, and a commitment to software craftsmanship.

We develop everything from embedded systems and firmware to cloud APIs and React frontends. In this role, your focus will be modern .NET backend services powering our SaaS infrastructure.

Core Technical Competencies

Advanced C# & .NET

• Deep knowledge of modern C# (async/await, generics, LINQ, reflection, events/delegates).

• Strong understanding of OOP, SOLID principles, and common design patterns.

• Extensive experience with ASP.NET Core and modern .NET.

• Solid experience with dependency injection, configuration, logging, and middleware design.

APIs, Cloud & SaaS Architecture

• Designing and implementing secure RESTful APIs.

• Strong understanding of OAuth2, JWT, authentication and authorization.

• Experience deploying and operating applications in Azure.

• Experience with containerization (Docker; Kubernetes is a plus).

• Ability to design scalable, performant, and observable SaaS systems.

Data & Quality

• Experience with NoSQL document databases (e.g., CouchDB).

• Strong experience with automated testing (xUnit, NUnit, MSTest).

• Comfortable with TDD/BDD and CI/CD pipelines.

• Experience profiling and optimizing performance.

Security & OT (Preferred)

• Strong application security mindset (encryption, secure coding practices).

• Familiarity with OT protocols (Modbus, OPC UA, MQTT) and ICS/SCADA environments is a plus.

Agentic & AI-Augmented Engineering

We expect senior engineers to actively leverage modern AI tools as force multipliers — not shortcuts.

• Daily use of AI coding assistants (e.g., Claude Code, GitHub Copilot, ChatGPT or similar) in structured development workflows.

• Ability to decompose complex architectural or refactoring tasks into clear, iterative steps that can be executed collaboratively with AI tools.

• Experience generating production-ready code, tests, documentation, and refactorings using AI — while maintaining full ownership of quality.

• Strong critical thinking and engineering judgment: validating correctness, security, performance, and edge cases in AI-generated output.

• Ability to design structured prompts and workflows that improve repeatability and developer productivity.

• Interest in building internal tooling, automation, and AI-assisted development pipelines.

• Curiosity about integrating AI-powered capabilities into SaaS products is a plus.

We see AI-assisted development as part of modern software craftsmanship — combined with strong fundamentals and responsibility.

You Can Expect

At Secomea, we hire for teams — not just skillsets.

Each team owns its architecture within clear guardrails, maintains its own build and deployment pipelines, and continuously improves its engineering practices. We are steadily moving toward continuous delivery and expect you to contribute to a strong culture of quality, automation, and technical excellence.

We are driven by innovation and agile development, working closely with technology partners and customers worldwide.

Secomea has 150+ employees globally,