Senior RPG Developer for IBM iSeries / AS400

Description

Support the development, maintenance, modernization, and troubleshooting of business-critical applications running on IBM iSeries / AS400 for an international manufacturing and distribution customer. The role covers existing RPG-based systems, integrations, incident analysis, and improving application stability and maintainability.

As a Senior RPG Developer for IBM iSeries / AS400, you will develop and maintain IBM i applications and support operational and project-based work, including bug fixes, small enhancements, application analysis, technical documentation, integration topics, and modernization initiatives. This senior role requires independent work and communication with technical and business stakeholders.

Responsibilities

• Analyse IBM iSeries applications, databases, interfaces, and dependencies.
• Develop and maintain solutions using RPG IV, RPGLE, ILE RPG, Free-Format RPG, and CLLE.
• Design and optimise Db2 for i database structures and SQL queries.
• Diagnose complex application, database, integration, and system issues.
• Analyse job logs, batch processes, queues, and performance bottlenecks.
• Plan, test, implement, and document production changes.
• Build and maintain integrations using REST, SOAP, JSON, XML, ODBC, JDBC, and file transfers.
• Support integrations with ERP, CRM, finance, manufacturing, logistics, and sales systems.
• Participate in automation, migration, and application modernisation projects.
• Cooperate with customers, external vendors, and internal technical teams.
• Provide advanced third-line support for critical incidents.

Required Technical and Professional Expertise

• Strong commercial experience with IBM iSeries / AS400 environments.
• Strong hands-on experience with RPG / RPGLE / ILE RPG.
• Practical knowledge of CL / CLLE.
• Good knowledge of Db2 for i and SQL.
• Experience with 5250-based applications and IBM i system commands.
• Ability to analyze application logic, job logs, system messages, and data issues.
• Experience with file-based integrations, including IFS, SFTP/FTP, CSV, and XML.
• Understanding of enterprise application support and production troubleshooting.
• Ability to read, understand, and safely modify legacy code.
• English at minimum B2 level.

Nice to Have

• Experience with free-format RPG or SQLRPG.
• Experience with REST APIs, JSON, XML, or middleware integrations.
• Knowledge of RDi, VS Code / Code for IBM i, or similar modern development tools.
• Experience with ODBC/JDBC integrations.
• Knowledge of DDS, Query/400, or legacy green-screen applications.
• Experience in manufacturing, logistics, ERP, warehouse, or SAP-integrated environments.
• German language skills.

Non-Technical Requirements

• Strong analytical and problem-solving skills.
• Ability to work independently in a remote support model.
• Ownership mindset and responsibility for delivered changes.
• Good communication skills with technical teams and business users.
• Ability to explain technical issues clearly and structurally.
• Attention to detail when working with business-critical systems.
• Readiness to work with legacy systems while supporting gradual modernization.
• Customer-oriented approach and ability to work in an international environment.

Benefits

• B2B or employment contract.
• Working with latest technologies.
• Industry-leading healthcare and comprehensive medical coverage (Luxmed, Multisport).
• Opportunities to enhance qualifications through MS certifications, Udemy courses, and more.
• Customizable one-to-one English or German lessons.
• Modern computer equipment.
• Networking and connection opportunities, including get-togethers and team-building events.
• Employee referral programme.
• Flexible working schedule.
• 100% remote work with occasional travel to customers around Europe.