Sr. Software Developer

The Senior Software Developer role requires a deep expertise in Java SE 11, strong full-stack skills, and hands-on experience in architecting and deploying applications on Amazon Web Services (AWS). This role focuses on building scalable, secure, cloud-native systems using AWS best practices. The role will drive technical strategy, mentor engineers, and shape high-impact cloud solutions for the DoD on AWS GovCloud. This role emphasizes backend architecture, distributed systems, API development, and cloud-native engineering, while also leveraging full-stack fundamentals (HTML, CSS, SQL) to deliver end-to-end solutions. NOTE: This role is contingent on the contract being awarded, * Architect, design, and implement backend services, microservices, and RESTful APIs using Java SE 11.

• Leverage Java SE 11 capabilities (e.g., var, enhanced HTTP Client, modern JVM improvements) to build efficient and maintainable components.
• Design efficient data models and schemas using SQL
• Contribute to front-end integration using HTML5, CSS3, and foundational JavaScript.
• Develop secure, high-availability distributed systems aligned with AWS best practices.
• Implement robust error handling, caching strategies, and performance optimizations across backend services.
• Integrate with databases, message queues, API gateways, and third-party systems
• Apply AWS Well-Architected Framework principles to ensure operational excellence, security, reliability, performance, and cost efficiency.
• Conduct in-depth code reviews, provide technical mentorship, and drive engineering best practices.
• Optimize systems for performance, observability, monitoring, security, and fault tolerance.
• Work closely with DevOps teams to build and maintain CI/CD pipelines, deployment workflows, and cloud-based infrastructure.
• Support operations and sustainment activities.
• All other duties as assigned by management.

• Bachelor's degree in computer science or a technical field
• 10+ years developing complex support applications with proven leadership in legacy software rebuilds
• 10 years working in Java Standard Edition 11
• 10 years AWS and Cloud computing experience
• Front and back-end development knowledge in JAVA, HTML, SQL, CSS
• Experience in cloud computing.
• Excellent communication and management skills.

Certifications Preferred:

• Microsoft Certified Solutions Developer (MCSD)
• Zend PHP Certified Engineer
• Microsoft Certified Solutions Expert (MCSE)

Security Clearance Requirements:

• Must be a U.S. Citizen
• Must have an active DoD Secret clearance.

Who We Are: Oasys International LLC (Oasys) is a fast-growing federal government contractor delivering high-quality technology consulting and professional services to civilian, defense, and homeland security agencies. We have been recognized on Inc. 5000's list of the fastest-growing companies in America for five consecutive years and named a Best Places to Work in Virginia for the past two years. Our success is driven by a talented team of technologists, consultants, engineers, and subject-matter experts who support complex federal missions with integrity and excellence. At Oasys, we foster a collaborative, merit-based culture that values continuous learning, professional growth, and work-life balance. We are committed to creating an inclusive, engaging environment where employees are recognized for their contributions and empowered to build meaningful, long-term careers.