John R.
Senior Java Spring Boot Developer | REST APIs | Enterprise Systems
Senior Java Backend Developer with 10+ years building production systems using Spring Boot, REST APIs, and enterprise databases. CORE EXPERTISE: - Spring Boot, Spring MVC, Spring Data JPA, Spring Security - RESTful API design and development - Database design: MySQL, Oracle - Enterprise system integration - Production support and troubleshooting WHAT I DELIVER: - Spring Boot Enterprise applications and RESTful APIs - Database design and optimization (PostgreSQL, MySQL, Oracle) - System integrations and workflow engines - Application support and troubleshooting RECENT HIGHLIGHTS: - Built configurable workflow engine processing thousands of events - Designed multi-system integrations with comprehensive error handling - Kotlin + Spring Boot experience TECHNICAL SKILLS: Java, Spring Boot, Spring Framework, Kotlin, REST APIs, PostgreSQL, MySQL, AWS, Docker, Git, Agile/Scrum MICROSERVICES KNOWLEDGE: - Strong understanding of microservices architecture patterns through coursework and demo projects. Seeking opportunities to apply this knowledge in production environments and build distributed systems expertise under experienced architects. I have a 5.0 Upwork rating and clients describe me as "professional, responsive, and genuinely committed to delivering high-quality work." Available for long-term contracts (30+ hours/week).
Earnings and projects
Last 6 months ÷ 6
Last 6 months: $247
Billed in all: $1,899$1.9k
$247 in the last 6 months
Across 2 contracts
Across 16 contracts
Earnings, last 30 days
Skill rankings: Top 20% in Spring Framework
Ranked by MRR among everyone on Upwork with the skill.
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