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# Senior Developer - Mainframe / Assembler (z/OS, TPF)

- **Company:** Lumen Solutions Inc.
- **Location:** Washington, DC, United States
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Application Programming Interfaces (APIs), Component-Based Software Engineering, Assembly Language, C++ (Programming Language), Databases, IBM DB2, Software Debugging, IBM WebSphere MQ, Systems Analysis, Mainframes, Enterprise Messaging Systems, Service Development Studio, Systems Integration, Z/OS, File Transfer Protocol (FTP), Enterprise Software Applications, Integration Frameworks, Api Management, Legacy Systems, Programming Languages
- **Published:** September 4, 2026
- **Apply:** https://www2.jobdiva.com/portal/?a=yyjdnwtj1vk20likwp2a7oa2mc2scw064c948z22g23e046qehohegye8oqt3zi6&compid=0/jobs/27717058#/jobs/27717058

## About the Role

Mainframe Environment

 * IBM z/OS
 * Experience with TPF-based systems.

Programming Languages

 * Assembly (Primary language)
 * C
 * C++

Integration Technologies
Experience working with enterprise integrations such as:

 * DB2 databases
 * REST or enterprise APIs
 * IBM MQ messaging
 * File-based integrations
 * SFTP data transfers

Developmental Responsibilities

 * Legacy system enhancements.
 * Integration design and implementation.
 * New service/component development.
 * System troubleshooting and debugging.

## Description

Client is seeking a Senior Developer with deep experience in IBM z/OS mainframe environments, specifically working with Assembly language and C/C++.
The developer will support and enhance a critical legacy application primarily written in Assembler, while also contributing to system integrations and new service development.
This role requires strong experience working with mainframe-based transportation or enterprise systems, along with the ability to analyze complex systems and design integration solutions across multiple platforms.

Primary Responsibilities

 * Enhance and maintain an existing mission-critical mainframe application written primarily in Assembler.
 * Perform system analysis and propose technical design solutions.
 * Develop and maintain components in Assembler and C/C++.
 * Design and implement integrations between legacy systems and enterprise services.
 * Develop and support API integrations as both a producer and consumer.
 * Work with messaging systems such as IBM MQ.
 * Build and maintain file-based integrations including SFTP-based data exchanges.
 * Support database interactions with DB2.
 * Collaborate with architecture and engineering teams to modernize and extend legacy systems.


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