Sr. Software Developer at Oasys – Fairfax, Virginia
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About This Position
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.
Position Summary:
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
Primary Responsibilities:
- 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.
Skills and Qualifications:
- 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.
Work Location:
- Fairfax, VA – Corporate Headquarters (Hybrid)
Oasys is proud to be an equal opportunity employer for all protected groups, including protected veterans and individuals with disabilities.
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Job Location
Job Location
This job is located in the Fairfax, Virginia, 22031, United States region.