NET Developer / L3 Application Support Engineer

You will be the primary point of contact for L3 application support on our web-based platforms, owning issues through to resolution rather than routing them onward. Diagnosing and troubleshooting complex application problems escalated from clients, including performance issues, bugs, and system errors. Tracing root cause through .NET application code and down into SQL Server. Delivering the fix, or working with the development team on it, rather than handing over a description of the symptom. A real part of the job is making the same problem stop coming back: conducting root cause analysis on recurring issues and putting preventive measures in place, monitoring application performance and recommending optimizations, and writing the standard operating procedures and troubleshooting guides that let other people resolve what used to reach you. You will also participate in deploying and testing updates, patches, and enhancements, and help end users understand the applications well enough to avoid predictable problems. You will work closely with development and infrastructure teams on the genuinely complex problems, and with stakeholders on communication while an issue is live. If you enjoy uncovering the root cause of complex issues and communicating clear, honest answers when others are waiting for them, this could be an excellent fit.

You will need:

4–8 years of industry experience, with substantial time in L3 or BAU support on web-based applications

Hands-on .NET for debugging and bug fixing: C#, ASP.NET, .NET Framework 4.0 and above, and .NET Core 8

Front-end troubleshooting in JavaScript and jQuery

Strong SQL Server: query writing and optimization, stored procedures, functions, triggers, and views, plus the analysis and debugging tools that go with them

Strong experience with SQL-based reporting, particularly SSRS

Genuine root cause analysis ability — finding causes, not just closing tickets

Excellent verbal and written communication for stakeholder and end-user interaction

A bachelor’s degree in Computer Science, Information Technology, or a related field

Source control familiarity, such as GitHub

Nice to have:

Sigma or Power BI · applications hosted on Microsoft Azure · familiarity with ITIL frameworks and support best practice · payroll, benefits, or HR domain knowledge · experience measurably reducing escalation volume.