Fujitsu and IBM Japan Collaborate on Modernization to Support Enterprise Digital Transformation

Fujitsu Limited (hereinafter 'Fujitsu') and IBM Japan, Ltd. (hereinafter 'IBM Japan') will accelerate their collaboration in the field of business system modernization (hereinafter 'modernization') to advance digital transformation and address challenges posed by legacy systems. This initiative is part of a partnership announced in September 2025.

Modernization is an essential initiative for advancing enterprise digital transformation. Successful modernization requires careful consideration of business characteristics, system requirements, and architectural features to select optimal technologies and programming languages. Effective modernization strategies include 'rewrite'—converting existing codebases to languages better suited for modern environments—and 'refactoring'—restructuring applications to improve maintainability and scalability.

Under this collaboration, the companies will expand modernization efforts centered on rewriting and refactoring, leveraging Fujitsu's source code conversion solution 'Fujitsu PROGRESSION' and IBM's AI agent-driven enterprise development support partner 'IBM Bob'. The focus will be on rewriting COBOL programs running on Fujitsu's mainframes and UNIX servers into Java, followed by refactoring the converted Java code. With technical support from Fujitsu, IBM Japan will lead the delivery of these solutions, enabling joint efforts that go beyond simple asset migration to support long-term digital transformation.

Background

For many enterprises, COBOL applications running on mainframes and UNIX servers represent critical business assets, embodying years of accumulated business processes and expertise. However, to advance digital transformation with a focus on data utilization and full-scale AI adoption, it is essential to redesign these applications into more flexible and scalable architectures. Additionally, Fujitsu has announced a roadmap for the end of sales and support for its mainframe and UNIX server lines (Note 1), making migration to next-generation platforms an urgent priority. Furthermore, the aging workforce of legacy-skilled engineers and growing talent shortages have exposed limitations in traditional, labor-intensive development and migration approaches, particularly in terms of quality, productivity, and migration timelines.

To address these challenges, Fujitsu and IBM Japan will combine their respective modernization expertise and technologies to jointly promote modernization strategies that ensure stable operations while enabling future growth.

Collaboration Details

Building on the above context, both companies will expand modernization initiatives centered on rewriting and refactoring. The joint solution will deliver particularly high value when, after thorough analysis of business and system characteristics, migration to Java is deemed the most rational choice.

High-Precision Source Conversion via 'Fujitsu PROGRESSION'

At the core of the solution is Fujitsu's source conversion tool 'Fujitsu PROGRESSION', which will be used to rewrite COBOL programs running on Fujitsu mainframes and UNIX servers into Java and other languages suitable for open environments. Leveraging Fujitsu's extensive knowledge, this rewrite process ensures consistency in business logic and compatibility with specifications, minimizing migration risks and enabling reliable system transitions. For this collaboration, IBM Japan has received systematic skill transfer from Fujitsu on 'Fujitsu PROGRESSION', establishing a capability to support diverse use cases.

AI Agent-Driven Modernization Support

IBM's AI agent-driven enterprise development support partner 'IBM Bob' will be used to automate post-conversion code correction and refactoring after COBOL-to-Java translation. This enables efficient and high-quality execution of traditionally labor-intensive tasks such as business logic validation and testing. Refactoring will emphasize structural improvements based on clean architecture principles, separating application components by function. Beyond rewriting, this approach transforms business systems into maintainable, scalable architectures capable of adapting to future changes and feature additions, thereby supporting the creation of higher-value system foundations.

Fujitsu is actively promoting customer modernization using AI services such as 'Fujitsu Application Transform powered by Fujitsu Kozuchi' (Note 2). Through this collaboration, the companies will integrate and deepen their respective solution and AI utilization expertise, accelerating modernization of Fujitsu's mainframe and UNIX server systems, as well as legacy systems from other vendors operating in Japan.

IBM Japan, with technical support from Fujitsu, will deliver advanced modernization solutions based on rewriting and refactoring. The solutions will be tailored to customers' specific business needs, system requirements, and architectures, enabling migration to next-generation hybrid cloud environments that are not dependent on any single infrastructure. By combining their expertise and technologies, the two companies will support the creation of flexible, future-ready foundations that generate sustained business value.

Future Outlook

By integrating their technologies and expertise, Fujitsu and IBM Japan will deliver innovative, high-quality modernization solutions. Moving forward, they will leverage insights gained through these initiatives to strengthen system foundations that support Japan's sustainable development and adaptability to change, using advanced technologies such as AI to build trust in society.

Trademark Information

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Notes

Note 1 Roadmap for End of Sales and Support for Mainframes and UNIX Servers:

Fujitsu mainframes: End of sales in FY2030, end of support in FY2035. UNIX servers: End of sales in FY2029, end of support in FY2034.

Note 2 'Fujitsu Application Transform powered by Fujitsu Kozuchi':

A service that uses 'Fujitsu Kozuchi' to analyze existing system source code and automatically generate design documentation.