Software Engineer III

Hollstadt Consulting; Minnesota; On-site; USD 90,000 - 130,000; Full time

Job summary

Hollstadt Consulting is seeking a Software Engineer III to support, enhance, and maintain business-critical applications built on the Microsoft technology stack. You will focus on sustaining and evolving existing systems, troubleshooting complex issues, and ensuring security, reliability, and performance of established platforms.

The ideal candidate will have strong experience with C#, .NET Framework, ASP.NET Web Forms, SQL Server, and Azure-hosted applications, and will navigate legacy systems

Qualifications

• 5+ years of experience developing and supporting applications using C#, .NET Framework, ASP.NET Web Forms, and SQL Server.

Responsibilities

• Support, maintain, and enhance existing applications built using C#, .NET Framework, ASP.NET Web Forms, and SQL Server.
• Diagnose, troubleshoot, and resolve application defects, performance issues, and production support incidents.
• Implement business-requested enhancements and system improvements within existing application architectures.
• Analyze legacy codebases to identify opportunities for stability, maintainability, and performance improvements.
• Collaborate with business stakeholders, product owners, and technical teams to understand and implement changing business requirements.
• Create and maintain technical documentation related to application functionality, support procedures, and system architecture.

Skills

C#

.NET Framework

ASP.NET Web Forms

SQL Server

Azure

Azure DevOps

CI/CD

Security best practices

Troubleshooting

Communication

Tools

Azure DevOps

CI/CD tooling

Job description

We are seeking a skilled Software Engineer III to support, enhance, and maintain business-critical applications built on the Microsoft technology stack. This role will focus primarily on sustaining and evolving existing systems, troubleshooting complex issues, implementing application enhancements, and ensuring the security, reliability, and performance of established platforms.

The ideal candidate will have strong experience working with C#, .NET Framework, ASP.NET Web Forms, SQL Server, and Azure-hosted applications, and be comfortable navigating and improving legacy systems while supporting ongoing business needs. Success in this role requires strong problem-solving skills, attention to detail, and the ability to balance technical debt remediation with day-to-day enhancement and support activities.

Key Responsibilities

Application Maintenance & Enhancement

• Support, maintain, and enhance existing applications built using C#, .NET Framework, ASP.NET Web Forms, and SQL Server.
• Diagnose, troubleshoot, and resolve application defects, performance issues, and production support incidents.
• Implement business-requested enhancements and system improvements within existing application architectures.
• Analyze legacy codebases to identify opportunities for stability, maintainability, and performance improvements.
• Collaborate with business stakeholders, product owners, and technical teams to understand and implement changing business requirements.
• Create and maintain technical documentation related to application functionality, support procedures, and system architecture.

Legacy System Support

• Provide ongoing support for legacy applications and integrations that support critical business processes.
• Maintain and optimize existing APIs, integrations, scheduled processes, and background services.
• Assist with technical debt reduction through code refactoring, component upgrades, and remediation activities.
• Evaluate system issues and recommend practical solutions that balance business needs, cost, and risk.
• Participate in application upgrade efforts, patching activities, and platform maintenance initiatives.

Security & Compliance

• Follow secure coding practices and organizational security standards when implementing changes.
• Support management of application secrets, certificates, and access controls using Azure services where applicable.
• Ensure applications meet established authentication, authorization, and data protection requirements.
• Assist with remediation of security findings and compliance-related enhancements.
• Support adherence to regulatory and corporate compliance requirements, including PCI DSS where applicable.

Production Support & Monitoring

• Monitor application health, performance, and reliability using Azure monitoring and logging tools.
• Investigate production issues and perform root-cause analysis to prevent recurring problems.
• Support incident resolution efforts and collaborate with infrastructure and support teams as needed.
• Identify opportunities to improve application performance, stability, and operational efficiency.

DevOps & Release Support

• Participate in application deployments and release activities using Azure DevOps.
• Maintain and improve existing CI/CD processes to support reliable application delivery.
• Assist with environment management, configuration updates, and deployment troubleshooting.
• Support testing efforts across development, QA, and production environments.
• Write clean, maintainable, and well-documented code.
• Participate in peer reviews and contribute to development best practices.
• Work effectively across distributed teams using collaborative and asynchronous communication.
• Contribute to continuous improvement efforts focused on system reliability, maintainability, and supportability.

Qualifications

• 5+ years of experience developing and supporting applications using C#, .NET Framework, ASP.NET Web Forms, and SQL Server.
• Strong experience working with and maintaining legacy enterprise applications.
• Experience troubleshooting complex application, database, and integration issues in production environments.
• Familiarity with Azure-hosted applications and related services.
• Working knowledge of Azure DevOps and CI/CD processes.
• Experience with application security best practices and compliance requirements.
• Strong SQL development, query optimization, and database troubleshooting skills.
• Excellent analytical, debugging, and problem-solving abilities.
• Ability to work independently while collaborating effectively across technical and business teams.

Nice to Have

• Experience supporting applications undergoing gradual modernization efforts.
• Exposure to .NET Core/.NET 8, REST APIs, and cloud-native architectures.
• Experience with Azure Key Vault, Application Insights, and Azure Monitor.
• Knowledge of PCI DSS or other regulated environments.