Senior .NET Developer / Integration Engineer

Company Description

ThreatXIntel is a startup focused on delivering customizable and cost-effective cyber security solutions tailored to meet the unique needs of businesses. Specializing in services such as cloud security, web and mobile security testing, and DevSecOps, we provide comprehensive protection for digital assets. Our expert team uses a proactive approach to identify and address vulnerabilities, ensuring businesses of all sizes can safeguard their critical data. ThreatXIntel is committed to empowering organizations with high-quality security services, enabling them to focus on growth in a secure digital environment.

Role Description

We are seeking a Senior .NET Developer / Integration Engineer with strong experience in enterprise application development and complex system integrations. The ideal candidate will have deep expertise in ASP.NET, Web APIs, Azure, SQL Server, and cross-system integrations, along with exposure to retirement or 401(k) business processes.

This role involves maintaining and modernizing legacy applications, building scalable APIs, handling XML/XSLT transformations, and integrating with third-party systems such as Salesforce and payroll platforms.

Key Responsibilities

• Develop, maintain, and modernize enterprise applications using ASP.NET (Web Forms and MVC)
• Design and develop RESTful APIs using .NET Core / .NET 6/7/8
• Translate 401(k) retirement business rules into technical specifications and automated workflows
• Build and maintain Windows Services and background processing components
• Develop and optimize XSLT transformations for XML data processing
• Integrate third-party systems including payroll providers, TPAs, and Salesforce (DBAmp)
• Deploy, monitor, and maintain applications in Microsoft Azure
• Optimize SQL Server performance through stored procedures, indexing, and query tuning
• Troubleshoot complex production issues across application, database, and integration layers

Required Technical Skills

401(k) Business Knowledge (Preferred)

• Understanding of retirement plan workflows such as enrollment, contributions, loans, distributions, vesting, and compliance testing
• Familiarity with payroll data flows and recordkeeping integrations
• Ability to translate business rules into automated processes

ASP.NET and Web APIs

• Strong experience in ASP.NET Web Forms and MVC
• Expertise in building RESTful APIs using .NET Core and .NET 8
• Strong understanding of middleware, dependency injection, filters, and API versioning
• Experience implementing secure APIs using OAuth2, JWT, Azure AD, or API keys

C# Programming

• Advanced proficiency in C# including async/await, LINQ, generics, delegates, and events
• Strong object-oriented design and SOLID principles
• Experience implementing design patterns such as Singleton, Factory, Strategy, and Repository

Integration and Services

• Experience building and consuming SOAP and REST services
• Experience with Windows Services for scheduled/background processing
• Strong knowledge of logging, monitoring, and reliability strategies

Azure and Cloud

• Hands-on experience with Azure App Services, Functions, Key Vault, Storage Accounts, and Application Insights
• Experience with Azure DevOps CI/CD pipelines
• Understanding of VNETs, private endpoints, and cloud networking basics

Databases and Integration

• Strong SQL Server experience including stored procedures, triggers, indexing, and query optimization
• Experience with Oracle SQL/PLSQL (nice to have)
• Experience integrating Salesforce using DBAmp
• Understanding of ETL workflows and cross-system data integrity.

Nice to Have

• Experience with SSRS, SQL Jobs, and automation scripts (PowerShell preferred)
• Strong debugging skills across .NET, SQL, and integration layers