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Aptimized

Senior Java Application Developer

On site

Washington, United states

$ 2 /year

Senior

Freelance

22-01-2026

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Skills

Communication Time Management Java JavaScript HTML CSS SQL Vulnerability Assessment GitLab CI/CD DevOps Docker Kubernetes Monitoring Version Control Azure DevOps Problem-solving Attention to detail Windows Programming Databases git jquery SQL Server Azure Software Development Spring Hibernate Maven Gradle

Job Specifications

Senior Java Application Developer

Washington, DC - ONSITE

Type: Multi-year Contract

US citizenship required per government contract

Must be able to obtain Public Trust clearance

We seek a Senior Application Developer with Java experience and a strong aptitude in modernizing systems. The incumbent will support up to 3 legacy mission-essential systems in the upgrade from Java/JDK 8 to Java/JDK 21 technology and beyond with operations and maintenance.

The Senior Application Developer will leverage knowledge of Object-Oriented Programming, software development methodologies, and the Java language to seamlessly transition our systems to the desired version. The position requires expertise in technologies such as Servlet, JSP, Tag Library, JavaBean, and SQL Server database, invaluable in ensuring smooth and successful migration.

Proficiency in tools like Maven, JavaScript, jQuery, Knockout.js, HTML, and CSS is valuable for modernizing the user interface and enhancing the overall user experience. Incumbent must be well-versed in Windows authentication, SSL, session management, and Single Sign-On (SSO) technologies, familiarity with Spring, Spring MVC, and ORM technologies like Hibernate and JPA - these are instrumental in seamlessly integrating the upgraded systems with our existing infrastructure.

Familiarity with RESTful web services, JSON parsing, and multipart/form-data file management is highly valued, as is expertise in vulnerability remediation techniques such as CSRF, SQL injection, XSS, and reflection attacks.

Upgrade experience:

• Previous experience successfully migrating Java applications across multiple major versions

• Knowledge of common pitfalls and solutions when upgrading Java applications

• Understanding of deprecated features and their modern replacements

• Experience identifying and resolving compatibility issues

Build, Deployment and CI/CD:

• Proficiency with build tools (Maven/Gradle)

• Experience updating build pipelines to accommodate newer Java versions

• Dependency management skills and handling library compatibility challenges

• Experience with continuous integration/continuous deployment (CI/CD) pipelines (Azure DevOps, GitLab)

Operations and Maintenance Skills:

• Experience with application performance monitoring tools and techniques

• Knowledge of log management and analysis systems

• Ability to create and maintain runbooks for operational procedures

• Proficiency in identifying and resolving production issues

• Understanding of JVM tuning and garbage collection optimization

• Experience implementing and maintaining automated health checks

• Knowledge of security patch management and vulnerability assessment

Additional Technical Skills:

• Version control with Git

• Familiarity with application servers (e.g., Tomcat, WebSphere, WildFly)

• Knowledge of common enterprise integrations (SQL Server databases, messaging systems)

• Experience with containerization technologies (Docker, Kubernetes) is a plus

Soft Skills:

• Excellent written and verbal communication skills

• Strong problem-solving abilities and attention to detail

• Ability to document migration processes, decisions, and technical debt

• Self-motivated with the ability to work independently

• Collaborative approach when working with existing development teams

• Strong time management skills to deliver migration within schedule constraints

• Experience providing on-call support and incident management

About the Company

Operating globally, Aptimized is a premium ERP, HCM, and Technology Optimization Consulting agency. Our team at Aptimized focuses on helping our customers become intelligent enterprises through leveraging creative technology solutions. At Aptimized, we prioritize our clients' needs and create tailor-made solutions to deliver success. We understand success is not achieved through chance. We listen to your concerns. We consult with your organization. We accelerate your business. Visit us at our website to learn more about w... Know more