Senior Java Developer: Connex Payment Switch Expert Remote

Greymatter Innovationz; Illinois; Hybrid; USD 120,000 - 180,000; Full time

Job summary

Greymatter Innovationz is seeking a Senior Java Developer with expertise in Connex Payment Switch to design, develop, and maintain high-volume payment applications. The role focuses on Java/Spring Boot microservices, ISO 8583 messaging, and integration with banking networks in a hybrid environment in Illinois.

The ideal candidate has 8+ years of Java development experience, strong Core Java, Spring Boot, and REST API skills, plus experience with payment processing and related databases.

Qualifications

• 8+ years of Java development experience.
• Experience with Connex Payment Switch or similar payment switch platforms.
• Experience with ISO 8583 messaging standards, EMV, and card payment flows.
• Experience building Java/Spring Boot microservices and REST APIs.

Responsibilities

• Design, develop, and maintain high-volume applications on the Connex Payment Switch platform.
• Support transaction processing for credit, debit, ATM, POS, and digital payment channels.
• Build scalable Java/Spring Boot microservices and integrate switch apps with external banking networks.
• Handle production support, RCA, and performance optimization for mission-critical systems.

Skills

Core Java (8/11/17)

Spring Boot

Microservices

REST APIs

CI/CD

Git

Linux/Unix

Tools

Oracle

SQL Server

PostgreSQL

Job description

Greymatter Innovationz is seeking a Senior Java Developer with expertise in Connex Payment Switch to design, develop, and maintain high-volume payment applications. The role focuses on Java/Spring Boot microservices, ISO 8583 messaging, and integration with banking networks in a hybrid environment in Illinois.

The ideal candidate has 8+ years of Java development experience, strong Core Java, Spring Boot, and REST API skills, plus experience with payment processing and related databases.