Freelance Web Developer

An experienced Java developer is required to support the modernisation of a payment processing application. The role involves enhancing and maintaining a Java-based payment switch with a focus on security, PCI DSS compliance, and integration with Thales and Futurex HSMs. The developer will collaborate closely with a cross-functional team, including Android developers, to deliver a secure, scalable, and high-quality system. Responsibilities include developing APIs, supporting frontend integration, implementing modern architectural approaches such as microservices and cloud-native design, and ensuring the use of agile methodologies throughout the project lifecycle.

Requirements

• Proven expertise in Java development for enterprise applications
• Experience with application servers (JBoss, Tomcat, WebLogic)
• Strong understanding of cryptography, PCI DSS compliance, and secure development lifecycles
• Familiarity with payment processing workflows and related technologies
• Hands-on experience with HSM integration (Thales, Futurex)
• Proficiency in API development and frontend frameworks (ReactJS or Angular)
• Knowledge of modern software architecture (microservices, cloud-native)
• Experience implementing CI/CD pipelines and using code analysis tools
• Solid understanding of TDD and agile methodologies
• Strong problem-solving skills and ability to contribute to business analysis activities
• Remote availability with commitment to a full-time contract engagement

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