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Crystal Equation Corporation

Java Full-Stack Developer

On site

Ridgefield park, United states

$ 55 /hour

Senior

Freelance

22-01-2026

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Skills

Communication Java JavaScript Kotlin HTML CSS Incident Response CI/CD DevOps Monitoring Problem-solving Architecture Application Architecture angular react Spring Spring Boot Full-Stack Development CI/CD Pipelines Android

Job Specifications

Yearlong, W2 contract

No C2C/C2H or visa sponsorships/transfers

Summary:

This role primarily focuses on Java-based Full-Stack application development, while also requiring the ability to support, maintain, and modify existing Android Mobile Applications.

The ideal candidate is a senior Java Full-Stack developer who can understand Android mobile application codebases and perform basic modification, build, and deployment tasks to ensure service continuity and operational stability.

Key Responsibilities:

Primary Responsibilities – Java Full-Stack Development

Lead and perform Java Full-Stack application development as the primary responsibility
Design, develop, and enhance backend services using Java, Spring / Spring Boot
Implement and maintain frontend components using HTML, CSS, JavaScript and modern frameworks
Support existing Java-based services and develop future enhancements based on business requirements
Secondary Responsibilities – Android Mobile App Support Provide operational support and maintenance for existing Android Mobile Applications
Understand Android application architecture and source code
Perform minor code changes, bug fixes, build, and deployment for Android applications
Support incident handling and troubleshooting related to Android mobile services
Operations & Service Stability Provide application-level operational support for both Java and Android systems
Participate in incident response, root cause analysis, and corrective actions
Ensure system stability, service continuity, and reduced operational risk
Knowledge Continuity & Collaboration: Maintain technical documentation and support knowledge transfer
Collaborate with cross-functional teams to ensure smooth operations and enhancement delivery

Required Qualifications:

Bachelor’s degree in Computer Science, Engineering, or a related field (or equivalent experience)
9+ years of professional experience in Java Full-Stack application development
Strong expertise in:
Java, Spring / Spring Boot
Web technologies (HTML, CSS, JavaScript, React/Angular or equivalent)
RESTful API design and database integration
Experience in application operations, maintenance, and incident support
Android Experience Requirements (Support-Oriented)Ability to understand existing Android Mobile App source code
Experience or capability to:
Modify existing Android code (Kotlin and/or Java)
Build and package Android applications
Perform deployment and operational support tasks
Senior-level Android development experience is NOT required
Junior-level Android skills are acceptable, as long as the candidate can independently support maintenance, build, and deployment

Preferred Qualifications:

Experience supporting enterprise-scale or production-critical systems
Familiarity with DevOps practices, CI/CD pipelines, and monitoring tools
Experience working in cloud or hybrid infrastructure environments
Background in both development-focused and operations-focused roles
Key Competencies: Strong ownership mindset for application stability and service continuity
Effective problem-solving and incident response skills
Clear communication with technical and non-technical stakeholders
Ability to prioritize Java Full-Stack development while handling Android support needs

Pay range is $50 - $55 per hour with full benefits available, including paid time off, medical/dental/vision/life insurance, 401K, parental leave, and more. Our compensation reflects the cost of labor across several US geographic markets. Pay is based on several factors including market location and may vary depending on job-related knowledge, skills, and experience.

THE PROMISES WE MAKE:

At Crystal Equation, we empower people and advance technology initiatives by building trust. Your recruiter will prep you for the interview, obtain feedback, guide you through any necessary paperwork and provide everything you need for a successful start. We will serve to empower you along the way and provide the path for your professional journey.

For more information regarding our Privacy Policy, please visit crystalequation.com/privacy.

About the Company

Crystal Equation (CE) is a certified Women-Owned Business that empowers people and advances technology initiatives by building trust. We actively identify needs, provide ongoing communication and appropriately place expertise toward contract staffing, direct hiring and managed services. We specialize in sourcing and placing talented IT/Technical engineers, and solve the staffing equation by finding the perfect match for both our clients and candidates. We deliver the right candidate by pinpointing the client's need, and exce... Know more