About our client

Our client is a leading technology provider delivering scalable, secure, and high-performing solutions to enterprise customers. They are now seeking a Senior .NET Developer to join their remote Northern Ireland team, working on mission-critical applications that impact customers across multiple sectors. This role offers the chance to work on complex systems, leverage modern cloud technologies, and contribute to a collaborative engineering culture.

Job Summary

As a Senior .NET Developer, you will design, develop, and maintain enterprise-grade applications, frameworks, and workflows. You will work across the full software development lifecycle, from architecture and design to testing and deployment. The role demands hands-on coding experience, a strong focus on quality and testing, and the ability to collaborate with cross-functional teams to deliver scalable, secure, and maintainable solutions.

Key Responsibilities

• Architect and develop applications, workflows, and prototypes to meet business needs.
• Refactor and extend existing codebases to fix defects and add functionality.
• Build enterprise-grade frameworks for engineers, prioritising security, scalability, and configurability.
• Develop complete test plans, including unit, integration, and end-to-end tests, ensuring high code coverage.
• Resolve defects throughout QA, pre-production, production, and post-release cycles.
• Refine functional requirements and produce detailed technical specifications.
• Generate clear technical documentation to communicate architectural and design decisions.
• Communicate and collaborate across teams, stakeholders, and external partners to drive engineering efforts.

Essential Skills & Experience

• 5-7+ years' hands-on experience with C#/.NET development.
• Strong experience with Azure/cloud technologies and/or relevant accreditations.
• Proven experience building secure, standards-compliant applications and APIs (REST, SOAP, XML/JSON).
• Solid understanding of design patterns, multi-tenant SaaS architectures, and enterprise-grade systems.
• Strong TDD mindset and experience writing extensive automated tests.
• Experience with NoSQL databases (Cassandra, Cosmos DB, or similar) and relational databases (SQL Server, Oracle).
• Familiarity with message queue systems (RabbitMQ, Kafka, MSMQ, Event Hub).
• Experience with .NET Core, microservices, and distributed systems.
• Exposure to Agile methodologies (Scrum, Extreme Programming) and tools such as Git, Jira, and Confluence.
• Ability to work in a fast-paced environment delivering iterative, mission-critical projects.

Desirable Skills

• Experience across multiple platforms/languages (Java, Microsoft stack, Open Source technologies).
• Familiarity with cloud-first design and serverless architectures.
• Strong problem-solving, analytical, and collaboration skills.

Education

• Bachelor's degree in Computer Science, Software Engineering, or a related field (Master's preferred).

Why Join?

• Fully remote working across Northern Ireland.
• Competitive salary up to £55k, depending on experience.
• Opportunity to work on mission-critical, enterprise-grade applications.
• Collaborative, supportive culture with mentoring and career growth opportunities.
• Exposure to cutting-edge cloud and distributed system technologies.

Skills: C# .NET Azure SQL