Senior .NET Developer

ITCON Services is seeking a highly experienced Senior Developer for a contingent position to provide operations, maintenance, and modernization of system that includes user forms, the entry, validation, certification, approval, and posting of data and centralized data warehouse to support reporting of program information. The Senior Developer will design, develop, enhance, deploy, and maintain Microsoft-based web applications, data integrations, databases, and reports using C#, ASP.NET/.NET, SQL Server, HTML, CSS, JavaScript, and related technologies. The role will provide hands-on technical application development, system architecture, database development, Azure infrastructure, configuration management, DevSecOps, automated testing, release management, troubleshooting, and technical documentation. The Senior Developer will play a key role in modernization by assessing legacy components, defining target-state architectures, decomposing and refactoring applications, modernizing data and reporting services, and supporting incremental migration to secure, scalable, cloud-based platforms. The role will develop application programming interfaces, reusable services, automated deployment capabilities, and data conversion solutions while ensuring continuity of mission operations, data integrity, interoperability, performance, accessibility, cybersecurity, and auditability throughout the transition. The candidate will complement business analysts, quality assurance engineers, database administrators, infrastructure teams, security personnel, help desk staff, and Federal stakeholders to implement change requests, resolve production issues, maintain data quality, and deliver reliable releases. The developer will participate in Agile ceremonies, requirements and design reviews, effort estimation, task decomposition, peer code reviews, unit and integration testing, User Acceptance Testing support, and post-release validation. This opening is for a full-time salaried contingent position supporting Federal civilian work performed off-site, with coordination across ITCON, client stakeholders, and Federal project teams as required. The applicant must be a United States citizen and be eligible to obtain and maintain a Public Trust clearance. Employment is contingent upon contract award, client approval, and completion of applicable background and onboarding requirements. Required Skills and Qualifications Bachelor's degree in computer science, Information Systems, Software Engineering, or a related field 10+ years of information technology experience, including 7+ years of hands-on software development experience 5+ years of experience developing and maintaining enterprise Microsoft web applications using C#, ASP.NET/.NET Framework or .NET, HTML, CSS, JavaScript, and related libraries Advanced experience with SQL Server, stored procedures, database objects, query optimization, data validation, troubleshooting, and production data support Experience supporting data warehouse, extract-transform-load, reporting, and analytics solutions, including SSRS and Excel-compatible outputs Experience analyzing requirements, designing technical solutions, preparing estimates, decomposing user stories, and producing maintainable code that satisfies functional and nonfunctional requirements Experience with Azure infrastructure and services, Windows Server environments, virtual machines, cloud migration, application configuration, monitoring, and operational support Hands-on experience with Azure DevOps or Team Foundation Server for source control, work-item management, build and release pipelines, branching, code reviews, and deployment traceability Experience building, maintaining, and troubleshooting continuous integration and continuous delivery pipelines and environment-specific release configurations Strong understanding of the software development lifecycle, Agile/Scrum practices, configuration management, change control, release management, and Federal production deployment processes Experience implementing change requests, production database change requests, defect corrections, emergency fixes, and application enhancements across development, test, staging, and production environments Experience supporting application modernization programs, including legacy system assessment, target-state architecture, incremental refactoring, component decomposition, API and service development, data migration, cloud adoption, and retirement or transition of legacy capabilities Ability to collaborate with architects, product owners, security teams, data specialists, and operations personnel to develop modernization roadmaps, technical spikes, proofs of concept, transition plans, and implementation increments that limit operational risk Experience designing secure RESTful APIs, integration services, modular application components, and automated data conversion and reconciliation processes for modernized platforms Experience conducting peer code reviews, unit testing, integration testing, regression support, automated testing, and requirements traceability in partnership with business and quality assurance teams Experience developing or maintaining Selenium and SQL automation scripts Experience supporting authentication, authorization, role-based access control, least privilege, secure coding, logging, auditability, and Federal cybersecurity requirements Experience supporting Section 508 accessibility compliance and remediating application accessibility defects Experience with database backup and restore, capacity planning, patching, migration, performance analysis, business continuity, and disaster recovery coordination Experience applying and validating operating system, database, middleware, and application patches while minimizing service disruption Experience developing and maintaining system design documents, interface specifications, deployment procedures, installation guides, database diagrams, class diagrams, release notes, and operations documentation Experience providing Tier 2 and Tier 3 production support, including issue reproduction, log and data analysis, root-cause analysis, defect resolution, escalation, and resolution validation Ability to communicate complex technical concepts clearly to technical and nontechnical stakeholders Strong written and oral communication skills, sound judgment, attention to detail, and ability to manage multiple high-visibility priorities independently Desired Skills and Qualifications Experience supporting systems with data-entry validation, certification, approval workflows, historical audit trails, and downstream financial or performance reporting Experience integrating with Federal identity services such as Login.gov and USDA eAuthentication Experience supporting interfaces or data exchanges with enterprise data sources Experience managing SSRS reports, SharePoint document libraries, and technical repositories Experience with application modernization, cloud migration, refactoring, API development, and transition from legacy Microsoft technologies Knowledge of NIST Risk Management Framework, secure software development practices, vulnerability remediation, and Federal information security controls Microsoft Azure, .NET, SQL Server, Agile, DevOps, or security-related certifications Experience operating within CMMI-aligned and ISO-based quality, service management, or information security processes ITCON Services is an equal opportunity employer. This position description summarizes the primary responsibilities and qualifications and may be adjusted based on final contract requirements.