Senior .NET Developer

Position: Senior .NET Developer
Location: New York City
Terms: 12+ Months

Job Description:
Senior Application Support & Development Engineer We are seeking a seasoned application support and development engineer to help maintain, enhance, and modernize a diverse application portfolio spanning legacy systems, Microsoft technologies, SharePoint, Power Platform, and SQL Server. This role is ideal for someone who is comfortable owning production issues, extending existing systems with care, and using AI-assisted development practices responsibly to improve speed, quality, and documentation. What You'll Do • Triage and resolve production incidents across the application portfolio, ranging from legacy to modern technology stacks, with clear root-cause writeups and durable fixes. • Deliver enhancements and feature work against existing .NET, ASP.NET, and VB.NET codebases while preserving behavioral fidelity and improving maintainability. • Quickly learn the functionality, architecture, and design intent of existing systems in order to troubleshoot effectively and deliver changes that align with established patterns. • Build, maintain, and extend solutions across SharePoint Online, SharePoint on-premises, and the Microsoft Power Platform, with a strong focus on Power Apps and Power Automate. • Maintain and optimize SQL Server databases, including stored procedures, indexes, job schedules, performance diagnostics, and schema changes as code. • Partner with business analysts and client stakeholders to translate support requests and enhancement needs into well-scoped, testable change items. • Apply AI-assisted workflows to root-cause analysis, patch drafting, regression test generation, and runbook documentation, while following team standards for review and verification. • Own post-incident reviews and turn systemic findings into backlog items that reduce recurrence.


Job Responsibilities:
Senior Application Support & Development Engineer
We are seeking a seasoned application support and development engineer to help maintain, enhance, and modernize a diverse application portfolio spanning legacy systems, Microsoft technologies, SharePoint, Power Platform, and SQL Server. This role is ideal for someone who is comfortable owning production issues, extending existing systems with care, and using AI-assisted development practices responsibly to improve speed, quality, and documentation.


What You'll Do

• Triage and resolve production incidents across the application portfolio, ranging from legacy to modern technology stacks, with clear root-cause writeups and durable fixes.
• Deliver enhancements and feature work against existing .NET, ASP.NET, and VB.NET codebases while preserving behavioral fidelity and improving maintainability.
• Quickly learn the functionality, architecture, and design intent of existing systems in order to troubleshoot effectively and deliver changes that align with established patterns.
• Build, maintain, and extend solutions across SharePoint Online, SharePoint on-premises, and the Microsoft Power Platform, with a strong focus on Power Apps and Power Automate.
• Maintain and optimize SQL Server databases, including stored procedures, indexes, job schedules, performance diagnostics, and schema changes as code.
• Partner with business analysts and client stakeholders to translate support requests and enhancement needs into well-scoped, testable change items.
• Apply AI-assisted workflows to root-cause analysis, patch drafting, regression test generation, and runbook documentation, while following team standards for review and verification.
• Own post-incident reviews and turn systemic findings into backlog items that reduce recurrence.

What You Bring

• 8+ years of professional software engineering experience, including meaningful production support ownership and real accountability during incidents.
• Strong .NET, .NET Core, ASP.NET, C#, and VB.NET experience across Web Forms and MVC/Core applications.
• Confidence reading, debugging, and extending legacy codebases without defaulting to unnecessary rewrites.
• Ability to quickly understand existing system functionality, design, dependencies, and business workflows, then apply that knowledge to support, enhancement, and defect-resolution work.
• Practical understanding of IIS hosting, application configuration, deployment considerations, and application lifecycle behavior.
• Genuine comfort with VB.NET as a first-class requirement, including reading, debugging, and modifying existing code without friction.

• Solid SQL Server and T-SQL depth, including stored procedures, triggers, complex queries, execution plan analysis, index strategy, concurrency and locking, and schema migration practices.
• Hands-on SharePoint Online and/or SharePoint on-premises experience, including site and list administration.
• Production delivery experience with Power Apps, including canvas and model-driven apps, and Power Automate flows.
• A structured support mindset: disciplined incident triage, root-cause analysis, change management, testing, documentation, communication, and composure under production pressure.
• Daily, beyond-autocomplete proficiency with GitHub Copilot agent mode or comparable AI-assisted development tools, applied to investigation, patch generation, test scaffolding, and runbook authorship.
• Strong judgment in verifying AI-generated output before shipping code, documentation, or operational guidance.

Nice to Have

• Azure DevOps experience covering boards, CI/CD pipelines, and repos in a real team delivery context.
• Exposure to electric utility operations, IT/OT operations, or regulated-industry software environments.
• Power BI familiarity.
• Prior exposure to OpenROAD 4GL or Actian Ingres Database, even at a passing familiarity level.
• Curiosity and composure when learning unfamiliar legacy stacks, tracing bugs through them, and delivering reliable fixes.

Ideal Candidate Profile
The ideal candidate is a pragmatic senior engineer who can move confidently between production support, enhancement delivery, and legacy system troubleshooting. They can quickly pick up the functionality, design, dependencies, and business context of existing systems, then use that understanding to make thoughtful changes without disrupting business-critical behavior. They value stability as much as speed, communicate clearly during incidents, and know how to improve maintainability without unnecessary rewrites. They are also comfortable using modern AI-assisted development tools as part of a disciplined engineering workflow, with strong review habits and accountability for final results.