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# AS400 Senior Developer

- **Company:** VDart, Inc.
- **Location:** Dallas, TX, United States
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Db2400, Clean Code Principles, Application Programming Interfaces (APIs), Software Applications, IBM System I, Unit Testing, Business Software, Databases, Software Debugging, IBM RPG (Programming Language), Software Engineering, SQL Databases, System Integration Testing, Web Services, Test Scripts, Control Language, Restful APIs, Legacy Systems
- **Published:** August 18, 2026
- **Apply:** https://www.dice.com/job-detail/49ddfdb9-724d-47ba-bda9-d1de63cb97c6

## About the Role

* Please do additional diligence and assessment beyond traditional sourcing methods before submitting any candidate profiles. We are looking for exceptional talent with proven capability and reliability.

## Description

* The AS400 Developer is responsible for the full software development lifecycle of core business applications. This includes analyzing requirements, writing high-quality code, optimizing database performance, and integrating legacy systems with modern web services or APIs., * Write Code: Develop and modify application software using RPG III/IV, RPG LE, Free-Form RPG, and Control Language (CL).
 * Manage Databases: Design, maintain, and optimize DB2 for i databases using SQL, DDL, and DDS.
 * Modernize Systems: Convert legacy green-screen applications into modern, web-enabled interfaces or modern RPG architectures.
 * Integrate APIs: Build and consume RESTful web services to connect the AS400 system with external applications.
 * Troubleshoot Issues: Debug complex software anomalies, optimize long-running batch jobs, and resolve production critical errors.
 * Test Code: Conduct thorough unit testing, system integration testing, and support user acceptance testing (UAT).
 * Document Work: Create detailed technical specifications, system workflows, and operational runbooks. [2, 3, 4, 5, 6]


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