Senior .NET Application Support and Modernization Engineer
Job Summary / Overview
Our client is seeking a Senior .NET Application Support and Modernization Engineer to take ownership of a complex, Windows-based communications and integration platform. This role is responsible for ensuring production stability while driving the modernization of a diverse application ecosystem.
The platform consists of multiple interconnected components, including Windows Services, WinForms-based administrative tools, monitoring utilities, and partner-specific integration jobs. This position combines hands-on production support leadership with strategic modernization efforts, requiring a balance of operational excellence and forward-looking technical improvement.
Key Responsibilities
- Maintain stability and reliability of the platform in production environments
- Support and manage core runtime components, including:
- Communications service
- Scheduler service
- Integration execution service
- Setup and administration tools
- Job monitoring and reporting utilities
- Diagnose and resolve issues such as:
- Failed jobs and scheduling conflicts
- Transport and integration errors
- Configuration defects
- Partner-specific data issues
- Maintain and enhance a large library of integration jobs and shared utilities
- Support and improve WinForms-based administrative and configuration tools used by operations teams
- Review and enhance logging, diagnostics, and incident response processes
- Identify and rationalize duplicate code and overlapping solution components
- Collaborate with operations and business stakeholders to prioritize modernization initiatives based on risk and impact
- Lead modernization efforts while ensuring continuity of business-critical operations
- Reduce dependency on outdated frameworks and fragile deployment or assembly-loading patterns
- Improve system observability through better logging, health checks, and error handling
- Enhance build reproducibility and introduce automated validation practices
- Develop and execute a phased roadmap to reduce technical debt and improve system clarity and maintainability
Required Qualifications
- Extensive experience as a Senior C# / .NET Engineer supporting production business applications
- Strong expertise in .NET Framework (4.x and earlier) along with modern .NET development practices
- Deep experience with Windows-based enterprise systems, including:
- Windows Services
- WinForms applications
- Background processing and scheduled jobs
- Strong SQL Server skills, including performance tuning and production troubleshooting
- Experience working with file-based integrations and external data exchange workflows
- Proficiency with integration technologies and protocols, including:
- FTP, FTPS, SFTP
- SSH
- Certificates and encryption
- SOAP/XML-based integrations
- Demonstrated success modernizing legacy systems incrementally without full rewrites
- Strong decision-making skills related to risk management, sequencing, and production change control
Preferred Qualifications
- Experience in automotive, dealership, or OEM integration environments
- Familiarity with legacy source control systems (e.g., SVN, Vault-era repositories)
- Experience with ClickOnce deployments and signed assemblies
- Background in consolidating overlapping product lines into streamlined support models
- Experience simplifying or replacing complex support tooling with more efficient operational workflows
Additional Information
- This role operates at the intersection of production support and system modernization, offering a unique opportunity to influence both stability and long-term technical direction
- The environment includes a mix of legacy and evolving technologies, requiring adaptability and thoughtful engineering practices
- Candidates should be comfortable working in highly integrated, business-critical systems with multiple stakeholders
- The position emphasizes pragmatic modernization, operational excellence, and continuous improvement