Senior C# Developer

Join a well-established and forward-thinking organisation that’s investing heavily in its technology function. This is a senior opportunity to take ownership of business-critical applications while helping shape the future of an evolving Microsoft and AI-led development environment.

Role Overview

• Location: Watford (Hybrid)
• Package: Competitive salary + comprehensive benefits package (See more below)
• Industry: Energy

What You’ll Be Doing?

• Take ownership of a business-critical customer portal, driving its ongoing development, enhancement and long-term stability.
• Design, build and maintain robust backend services, APIs and integrations using the Microsoft technology stack.
• Deliver high-quality, well-tested code while contributing to architectural decisions and technical best practice.
• Support the modernisation of legacy applications and play a key role in migrating towards modern cloud-based solutions.
• Develop internal tools and applications while exploring AI technologies to improve business processes and efficiency.
• Collaborate closely with analysts, data specialists and wider stakeholders to translate business requirements into scalable technical solutions.
• Participate in code reviews, testing, documentation and agile ceremonies to ensure high development standards.
• Provide technical guidance to the wider team, acting as a senior technical voice without direct line management responsibilities.
• Support business-critical applications through second-line issue resolution and proactive monitoring of systems and integrations.
• Continuously evaluate emerging Microsoft technologies and recommend improvements that deliver genuine business value.

What we're looking for?

• Strong commercial experience developing with C# and .NET Framework.
• Expertise building RESTful APIs, backend services and ASP.NET applications.
• Solid knowledge of Microsoft SQL Server, including database design and optimization.
• Experience developing and deploying applications within Microsoft Azure environments.
• Comfortable working across both modern applications and legacy codebases.
• Strong understanding of software development best practices, testing and code quality.
• Experience using Git/GitHub, agile methodologies, Jira and Confluence.
• Ability to work independently, take ownership and deliver complex technical solutions.
• Excellent communication skills with the confidence to collaborate across technical and non-technical teams.
• Exposure to Microsoft Power Platform, AI tooling, Dynamics 365 integrations or Azure DevOps would be advantageous.

What’s in It for You?

• Competitive salary and attractive benefits package.
• Profit share scheme.
• Enhanced pension and annual leave.
• Private medical insurance, life assurance and income protection.
• Birthday off every year.
• Ongoing learning and development with access to online training.
• Career progression within a growing internal technology team.
• Modern offices with free parking
• Regular company events and a collaborative, people-first culture.
• The opportunity to influence technology strategy while working with modern Microsoft and AI technologies.

You bring the skills, we’ll bring the opportunity!

We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, colour, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.

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