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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Software Systems Engineer - **Company:** Nationwide IT Service, Inc. - **Location:** United States (Remote available) - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** .NET Framework, ADO.NET, Agile Methodology, Applications Architecture, Component-Based Software Engineering, Application Configuration Access Protocols, Unit Testing, Microsoft Azure, C Sharp (Programming Language), Cloud Computing, CompTIA Security+, Continuous Delivery, Continuous Integration, Data Security, Software Debugging, Dependency Injection, DevOps, Performance Tuning, Scrum Methodology, Software Maintenance, Systems Development Life Cycle, Secure Coding, Software Deployment, Software Engineering, Software Systems, Systems Architecture, Systems Integration, Software Vulnerability Management, Enterprise Software Applications, ReactJS, Git, SC Clearance, Integration Tests, Information Technology, Front End Software Development, 3-tier Architectures, Restful APIs, Software Version Control, Devsecops, Legacy Systems - **Published:** October 26, 2026 - **Apply:** https://www.clearancejobs.com/jobs/9261506/software-systems-engineer ## About the Role Certification Requirements: CompTIA Security+, at least one Microsoft Azure certification (AZ-204, AZ-305, or AZ-400), and DoD 8140 baseline certification., * Minimum of five years of relevant software engineering experience. * Experience with .NET Framework, C#, REST APIs, React, Git, ADO.NET, and dependency injection. * Experience designing, developing, integrating, testing, debugging, and maintaining enterprise software applications. * Experience supporting software development, lifecycle activities, application modernization, and technical documentation. * CompTIA Security+ certification. * At least one of the following Microsoft Azure certifications: + Microsoft Certified: Azure Developer Associate (AZ-204). + Microsoft Certified: Azure Solutions Architect Expert (AZ-305). + Microsoft Certified: DevOps Engineer Expert (AZ-400). * DoD 8140 baseline certification. * Minimum Education No specific degree requirement identified in the provided minimum qualifications. Security Requirements * Favorable Tier 3/NACLC/ANACI investigation required at the time of proposal submission. ## Description Security Requirement: Favorable Tier 3/NACLC/ANACI investigation required at proposal submission. Secret clearance., Nationwide IT Services (NIS) is seeking a highly qualified Software Systems Engineer to support a federal IT application modernization and sustainment program for the Defense Logistics Agency (DLA). The Software Systems Engineer will design, develop, modernize, integrate, and sustain complex enterprise applications supporting a Department of Defense (DoD) mission. This position requires strong technical expertise in software engineering, application architecture, development, testing, debugging, and system integration. The successful candidate will modernize legacy applications, develop secure and scalable software solutions, and collaborate with multidisciplinary technical teams to enhance application functionality, performance, security, and reliability., * Design, develop, modernize, integrate, and sustain enterprise software applications supporting DoD mission requirements. * Provide technical engineering support throughout the software development lifecycle (SDLC), including requirements analysis, architecture, design, coding, testing, debugging, deployment, and documentation. * Develop and maintain applications using .NET Framework, C#, React, ADO.NET, and dependency injection design techniques. * Support modernization of legacy applications to modern .NET architectures and cloud-based environments. * Design, develop, integrate, and maintain REST APIs to support secure data exchange between internal and external systems. * Develop and enhance front-end and back-end application components to improve system functionality, performance, usability, and maintainability. * Utilize Git and established source code management practices to support version control, collaborative development, and software releases. * Participate in Agile software development activities, including sprint planning, backlog refinement, technical reviews, and iterative application delivery. * Support DevSecOps practices and continuous integration/continuous delivery (CI/CD) pipelines to automate software builds, testing, security assessments, and deployments. * Conduct unit testing, integration testing, debugging, and quality assurance activities to identify and resolve software defects. * Support application security testing, vulnerability remediation, and compliance with DoD cybersecurity standards and secure development practices. * Analyze existing application architectures and recommend technical improvements, system enhancements, and modernization solutions. * Develop and maintain technical documentation, including software design specifications, system architecture diagrams, interface documentation, and testing procedures. * Collaborate with software developers, systems administrators, cybersecurity professionals, and government stakeholders to resolve technical issues and support application modernization objectives. * Support user acceptance testing (UAT), troubleshoot identified defects, and implement corrective actions before production deployment. * Assist with application configuration, integration, performance optimization, and ongoing software maintenance. * Ensure software solutions align with established technical requirements, government standards, and program objectives.