Senior Java Full Stack Developer
Xcelo Group
Description
Work Location: O'Fallon, MO – Hybrid (Local Candidates Only / Strongly Preferred)
Work Experience: 7+ Years
Work Auth All Visas Accepted (No H1 and No Fake profiles)
We are looking for an experienced Senior Java Full Stack Developer to design, develop, and enhance a next-generation Decision Management Platform that processes and scores billions of payment transactions.
The ideal candidate will have strong expertise in Java, Spring, Hibernate, Angular/React, cloud-native architecture, and GenAI-enabled development, with experience building highly scalable, secure, and resilient enterprise applications.
Required Technical Skills
- Backend: Java 8+, J2EE, Spring 5, Hibernate, JSP, Servlets.
- Frontend: Angular or React, JavaScript, HTML, jQuery.
- APIs & Microservices: RESTful APIs, SOAP Web Services, enterprise application development.
- Databases: Oracle, SQL Server, MySQL, PostgreSQL, MongoDB.
- Cloud & DevOps: AWS or other cloud platforms, Jenkins, Maven, Gradle, Chef, Sonar.
- Application Servers: WebSphere, JBoss, Apache Tomcat.
- GenAI & Agentic AI: LLM integration, prompt engineering, agentic patterns, Claude Code, GitHub Copilot or similar tools.
- Methodologies: Agile, Waterfall, CI/CD, software development lifecycle (SDLC).
Key Responsibilities
- Design and develop scalable enterprise applications using Java, Spring, Hibernate, and Angular/React.
- Build and integrate REST/SOAP APIs and enterprise services.
- Develop and enhance real-time payment decisioning and transaction processing platforms.
- Design cloud-native solutions with high availability, scalability, security, and zero-downtime objectives.
- Improve application performance, reliability, and operational efficiency.
- Leverage GenAI and AI-assisted development tools for coding, testing, documentation, and troubleshooting.
- Explore GenAI use cases for application modernization and workflow automation.
- Collaborate with architects, product managers, and business stakeholders to deliver enterprise solutions.
- Implement CI/CD pipelines, code quality standards, and engineering best practices.
- Support compliance requirements, including PCI, GLBA, and applicable security standards.
- Participate in requirements gathering, technical design, prototyping, and production support.
- Mentor developers and contribute to architecture and performance improvements.
Qualifications
- Bachelor's degree in Computer Science, Information Technology, Engineering, or a related field, or equivalent experience.
- 7+ years of professional software development experience.
- Strong analytical, problem-solving, and communication skills.
- Experience with enterprise-scale applications and cloud-native architecture.
- Ability to work independently and collaborate with cross-functional teams.
- Payments or financial services industry experience preferred.
Important Submission Requirements
Local candidates preferred
Hybrid
Candidates must be located near O'Fallon, MO, and be available for the required hybrid onsite schedule.
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