TransUnion HPE NonStop COBOL Credit-Processing Modernization Case Study

Name: COBOL to Java Migration Case Study: Tandem Financial Application
Item: TransUnion
Rating: 5
Author: A.G.

TransUnion used SoftwareMining's automated, rule-based COBOL-to-Java translation toolkit to modernize more than 200 credit-processing applications running on HPE NonStop, formerly Tandem. The portfolio included approximately equal numbers of online and batch COBOL applications, which were translated into maintainable Java for deployment on a modern enterprise platform.

The modernization enabled TransUnion to retire the legacy platform while preserving the established processing behaviour of its business-critical credit applications.

Project at a Glance

Customer	TransUnion
Industry	Credit Reference Services
Legacy Platform	Tandem (HP NonStop) COBOL
Application Portfolio	More than 200 COBOL applications
Application Mix	Approximately 50% online and 50% batch processing
Target Platform	Java
Outcome	Successful production deployment with zero production outages and no post-go-live defects

Project Overview

As the Tandem systems reached end of life, TransUnion chose to move to Java rather than port and upgrade. The program portfolio included 200+ applications, split roughly half online and half batch.

We could not have completed this project without it. We have had zero production system outages caused by the new system and there have been no defects found. This was a huge effort and successful because of SoftwareMining.

Approach and Timeline

Automated translation of COBOL modules to Java, with targeted refactoring for readability and supportability.
Early stabilization: the first two months of conversion resolved the majority of compile and build issues.
Phased validation: online and batch flows verified against existing outputs and operational SLAs.

There were far less compilation errors than we planned for and the initial two months of COBOL to Java conversion shook out many issues. Very few occurred after that phase.

Results

Zero production outages caused by the new Java system since go live.
No post go live defects reported in translated components.
Faster integration with internal platforms via standard Java interfaces and tooling.

Business Benefits

Lower total cost: commodity hardware and simplified licensing.
Access to larger in-country talent pools for ongoing support and change.
Improved interoperability with enterprise services, APIs, and CI/CD pipelines.

As the technical lead summarized, the migration reduced costs and increased maintainability while meeting strict reliability targets.

To see how the same approach can work for your organization, see our modernization success stories or request an enterprise briefing.