Job Specifications
Senior Application Developer (Java Modernization | JDK 8 to JDK 21 | O&M)
Citizenship Requirement: U.S. Citizenship required per 8 U.S.C. 1324b(a)(2)(C)
Must be willing to work on location in Washington, DC
Position Overview
We are seeking a Senior Application Developer with strong Java expertise to modernize and sustain up to three (3) legacy, mission-essential systems. The primary initiative is upgrading applications from Java/JDK 8 to Java/JDK 21 (and beyond), ensuring secure, stable operations throughout the transition. This role combines hands-on development, migration engineering, and operations & maintenance (O&M), including performance, monitoring, security remediation, and production support.
Responsibilities
Lead and execute application upgrades from Java 8 to Java 21, including refactoring, dependency updates, and compatibility remediation.
Assess legacy codebases and design modern replacements for deprecated APIs/features.
Modernize UI components as needed using JavaScript, jQuery, Knockout.js, HTML, CSS.
Support and enhance web applications using Servlets, JSP, Tag Libraries, JavaBeans.
Develop and optimize database interactions with SQL Server (queries, stored procedures, performance tuning as needed).
Implement and support authentication/authorization mechanisms including Windows authentication, SSL/TLS, session management, and SSO.
Build and maintain RESTful services, integrations, and data exchange using REST, JSON parsing, multipart/form-data.
Perform security hardening and vulnerability remediation (e.g., CSRF, SQL Injection, XSS, reflection attacks).
Update and maintain build and deployment processes using Maven (or Gradle) and improve dependency management.
Enhance and support CI/CD pipelines (e.g., Azure DevOps, GitLab), including pipeline updates required for newer Java versions.
Participate in on-call rotation and incident management as required.
Produce clear technical documentation for migration decisions, processes, and technical debt.
Provide O&M support:
Monitoring, log analysis, incident triage, and production issue resolution
Runbook creation/maintenance and automated health checks
JVM tuning and garbage collection optimization
Patch management and vulnerability assessment support
Required Qualifications
Significant experience as a senior Java developer supporting enterprise applications.
Demonstrated success migrating Java applications across multiple major versions (specifically JDK 8 newer LTS strongly preferred).
Strong knowledge of OOP, enterprise Java web applications, and SDLC best practices.
Experience with Servlet/JSP/JSTL/JavaBeans applications.
Proficiency with SQL Server and SQL development/optimization.
Proficiency with Maven/Gradle, Git, and managing dependency compatibility issues.
Experience supporting or integrating:
Spring / Spring MVC
ORM technologies: Hibernate / JPA
Working knowledge of application servers such as Tomcat, WebSphere, WildFly (or similar).
Strong troubleshooting ability in production environments; able to work independently and collaboratively.
Excellent written and verbal communication; strong documentation habits.
Preferred Qualifications
Experience with Docker/Kubernetes containerization.
Experience with enterprise integrations (messaging systems, service-to-service integrations).
Experience improving observability (APM tooling, centralized logging, metrics, alerting).
As a requirement of this position, all candidates must be a U.S. Citizen. In accordance with 8 U.S.C. 1324b(a)(2)(C), Will not consider candidates for this position who do not meet the aforementioned conditions
About Us
ECCO Select is certified as a Women-owned, Minority-owned, Small Business Enterprise. We are a talent acquisition and advisory consulting company, specializing in providing people, process, and technology solutions for our clients’ needs. ECCO Select has experience in assisting our commercial and government clients successfully manage projects and programs that transform their business operations through a variety of IT solutions. We’re the talent behind the technology. To find out more about ECCO visit www.eccoselect.com.
Our Commitment
We would love to have you join our team! ECCO Select is committed to hiring and retaining a diverse workforce. ECCO Select’s policy is to provide equal opportunity to all people without regard to race, color, religion, national origin, ancestry, marital status, veteran status, age, disability, pregnancy, genetic information, citizenship status, sex, sexual orientation, gender identity or any other legally protected category.
Equal Employment Opportunity is The Law
This Organization Participates in E-Verify