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Closed on July 19, 2026.
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Job Description
SOSi seeks a Senior Application Developer on site at Fort Belvoir, VA to support a government customer, focusing on the design, development, integration, and maintenance of complex software applications with an emphasis on .NET Core and ITCD.
Responsibilities
- Design, build, test, and maintain high performance software systems
- Analyze business needs and translate them into technical specifications
- Lead the architecture and design of application components and integrations
- Perform code reviews to ensure accuracy, quality, and best practice adherence
- Troubleshoot and resolve complex issues across the application stack
- Collaborate with product managers, QA, DevOps, and other stakeholders
- Contribute to process improvements, automation, and engineering standards
- Mentor junior engineers and promote knowledge sharing within the team
- Stay current with emerging technologies and recommend suitable solutions
- Assist the project manager with project operations, planning, and execution
- Define objectives and effort estimates through research and stakeholder consultation
- Own the software development lifecycle from planning through deployment and maintenance
- Help develop project schedules and timelines for efficient delivery
- Create and maintain thorough documentation for all supported applications
- Manage technical issues related to the operation, maintenance, and modification of GOTS applications
- Collaborate with customer stakeholders to design or tailor software for operational efficiency
- Apply hardware and software engineering principles as appropriate
- Design or customize client software to improve operational effectiveness
- Monitor application performance and implement changes to optimize performance
- Analyze and design GOTS applications and systems to improve functionality and usability
- Provide evaluations and recommendations for GOTS applications to address complex challenges
- Adhere to all applicable agency policies, procedures, and regulations
- Provide technical guidance to junior developers and engineers
Requirements
- Bachelor's or master's degree in engineering, science, technical fields, or business management from an accredited institution
- At least 5 years of technical supervisory experience in an application or software development setting
- Active Top Secret clearance, or Secret with the ability to obtain Top Secret
- Experience with GOTS applications such as ARMIS, AAO, ACOTD, FACTS, MDR, or ADAMS
- Experience with Microsoft SQL Server and the .NET framework
- Experience with configuration management processes including Change Control Boards (CCB)
- Ability to schedule, track, and execute multiple concurrent projects
- Demonstrated ability to communicate with diverse stakeholders in multiple formats
- Baseline DoD 8570.01-M IAT II certifications (eg CCNA-Security, CySA+, GICSP, GSEC, Security+, CND, SSCP)
- 5 to 8+ years of professional software or application development experience
- Strong proficiency in modern programming languages and frameworks (C#, JavaScript, .NET, or equivalent)
- Hands-on experience with cloud platforms and services (AWS, Azure, or GCP)
- Proficiency with REST APIs, microservices, and application integration patterns
- Solid understanding of relational and NoSQL databases
- Experience with CI/CD pipelines, version control, and automated testing
- Strong analytical, problem solving, and communication skills
- Ability to work independently while contributing to team goals
Technologies
- .NET Core
- .NET Framework
- C#
- JavaScript
- Microsoft SQL
- ARMIS
- AAO
- ACOTD
- FACTS
- MDR
- ADAMS
- AWS
- Azure
- GCP
- REST APIs