via Adp
$145K - 175K a year
The Senior Full Stack Engineer will support the design and architecture of scalable APIs for enterprise applications and collaborate with engineers to integrate user interfaces with APIs. This role also involves modernizing legacy systems and providing solutions for migration while minimizing downtime.
Candidates must have a bachelor's degree and be U.S. citizens, with at least 8 years of experience in Java and 5 years in developing responsive web applications using React. Strong experience in API development and familiarity with CI/CD pipelines in cloud environments is also required.
ECS is seeking a highly skilled Senior Full Stack Engineer with extensive experience in designing, building and maintaining large scale API's for enterprise level applications to work remote and/or in our Washington DC area office in support of the Department of Homeland Security. This role will focus heavily on modernizing legacy systems with deprecated code bases, requiring both technical expertise and creative problem-solving abilities. You will play a critical role in rearchitecting our application's API infrastructure, ensuring scalability, reliability and long-term maintainability. Tools necessary for excelling in this role include Java (with Maven, Gradle, etc), JavaScript Frontend frameworks (React, Angular, etc), Elastic and other data sources, and DevSecOps in the Cloud. Key Responsibilities: * Support the design and architecture of robust, scalable API's for large enterprise level applications. * Integrate and operate CI/CD pipelines used for building and releasing code and container images. * Assess and refactor deprecated code bases implementing best practices for modernization and performance improvement. * Collaborate with engineers to integrate React-based user interfaces with scalable APIs, leveraging React expertise to enhance API interactions, support legacy system modernization, and ensure seamless functionality and optimal user experience. * Provide solutions for legacy system migration while minimizing system downtime and operational risks. * Identify and resolve technical debt in older systems while transitioning them to modern Java frameworks and tools. Salary Range: $145,000 - $175,000 General Description of Benefits [https://ecstech.com/careers/benefits] Qualifications * Bachelor's degree in a relevant field * Be a US Citizen * Ability to pass a Public Trust background investigation * 8+ years with Java (8 and beyond) with strong experience in legacy system modernization. * 5+ years developing responsive web apps using React, Redux, and modern JavaScript. * Strong background in API development, including 5+ years building RESTful microservices and service-oriented architectures. * 3+ years of experience with CI/CD pipelines and deploying/operating in AWS or Azure Cloud environments. * 3+ years of experience with Springboot or other stateless Java frameworks * 3+ years developing applications in a production setting and troubleshooting complex issues within legacy environments and proposing effective solutions. * Solid understanding of Git, version control workflows, and collaborative development practices. * Familiarity with CX and UI/UX principles and their application in modern software design. * Excellent communication skills with the ability to explain technical challenges and solutions to non-technical stakeholders.
This job posting was last updated on 12/6/2025