Sr. Java Developer

Posted 3 days ago

Worldwide

Summary

Summary: We are seeking an accomplished Senior Java Developer to drive the development and optimization of our e-commerce platform. The ideal candidate will bring extensive experience in Java, microservices architecture, and performance tuning, along with the leadership skills to mentor a growing development team and steer complex projects to success. Key Responsibilities Application Design & Development Architect, design, and develop high-performance, scalable Java-based e-commerce applications. Implement microservices and event-driven architectures to ensure modular and resilient systems. Performance Optimization & Scalability Monitor, analyze, and optimize system performance, memory usage, and throughput. Troubleshoot concurrency, threading, and performance bottlenecks using advanced profiling tools and techniques. Technical Leadership Mentor junior and mid-level developers, setting best practices in coding, testing, and deployment. Drive architectural decisions and technology choices aligned with business needs and industry standards. System Integration Integrate third-party APIs, payment gateways, and services to enhance platform capabilities. Implement caching solutions (e.g., Redis, Memcached) and messaging systems (e.g., RabbitMQ, Kafka) for efficient data handling.' Quality Assurance & Testing Champion test-driven development (TDD) and continuous integration/continuous delivery (CI/CD). Write and maintain robust unit, integration, and end-to-end tests using frameworks such as JUnit, TestNG, and Mockito. DevOps & Deployment Collaborate with DevOps teams to automate builds, deployments, and monitoring (e.g., Jenkins, GitLab CI, Docker, Kubernetes). Ensure high availability, fault tolerance, and seamless scalability in production environments. Security & Compliance Enforce secure coding practices, including data encryption, OAuth/JWT-based authentication, and compliance with PCI-DSS/GDPR where applicable. Continuously monitor and mitigate security vulnerabilities and threats. Documentation & Collaboration Produce clear, comprehensive technical documentation and architectural diagrams. Work cross-functionally with product managers, QA, UX designers, and other engineers to deliver robust solutions within agile sprints. Continuous Improvement Stay current with emerging trends, tools, and technologies to evolve and enhance our software development lifecycle. Propose and implement improvements to optimize code quality, productivity, and operational efficiency. Note: Please send a link to your updated CV, no uploaded CV will not be entertained. Qualifications: 5+ years of professional Java development experience, ideally on large-scale e-commerce or SaaS platforms. Demonstrated success in building and deploying microservices, distributed systems, and event-driven architectures. Technical Expertise Java Proficiency: Strong command of Java 8+ features (Streams, Lambdas), concurrency, memory management, and JVM internals. Frameworks & Libraries: Advanced experience with Spring Boot, Spring Data, Spring Security, Hibernate/JPA. API & Integrations: Experience creating RESTful APIs, integrating third-party services, and working with GraphQL (preferred). Database Systems: Hands-on experience with MySQL, PostgreSQL, or MongoDB; adept at writing complex queries and optimizing database performance. Messaging & Caching: Practical knowledge of message brokers (RabbitMQ, Kafka) and caching systems (Redis, Memcached). Build & CI/CD: Proficiency in Maven/Gradle, Git, Jenkins/GitLab CI, Docker, and Kubernetes for seamless development and deployment. Testing: Expertise in TDD, unit testing, integration testing, and test automation frameworks like JUnit, TestNG, and Mockito. Performance Monitoring & Profiling: Familiarity with tools like VisualVM, YourKit, or New Relic for troubleshooting and tuning. Soft Skills Leadership: Demonstrated ability to mentor developers and influence technical direction. Collaboration: Excellent communication skills, capable of working effectively with product owners, designers, and cross-functional teams. Adaptability: Thrives in a fast-paced, agile environment, reacting quickly to changing requirements. Problem-Solving: Proven analytical mindset and a pragmatic approach to solving complex challenges. ***Very important: Do take note that the applicant is required to share their updated CV with appropriate access. Applicants who are non compliant with this will be automatically ignored.***

  • More than 30 hrs/week
    Hourly
  • 6+ months
    Duration
  • Expert
    Experience Level
  • $22.00

    -

    $22.93

    Hourly
  • Remote Job
  • Ongoing project
    Project Type

Contract-to-hire opportunity

This lets talent know that this job could become full time.
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Skills and Expertise
Mandatory skills
Java
API
JavaScript
Spring Framework
Activity on this job
  • Proposals:50+
  • Interviewing:
    0
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since Jan 13, 2012
  • United States
    West Palm Beach2:27 PM
  • $948K total spent
    146 hires, 40 active
  • 211,665 hours

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