generative AI service
Figure: Fujitsu Application Transform powered by Fujitsu Kozuchi concept diagram

Fujitsu announced the launch of Fujitsu Application Transform powered by Fujitsu Kozuchi, a generative AI service that analyzes source code and automatically generates design documents, contributing to a reduction in work time of approximately 97%. Fujitsu will begin offering Fujitsu Application Transform powered by Fujitsu Kozuchi as a SaaS in Japan starting March 30, 2026. This service supports the modernization of companies and organizations by leveraging Fujitsu’s extensive system development expertise, proprietary technology, and generative AI to analyze COBOL and other source codes within existing legacy systems, automatically generating design documents to understand the system’s content.

Building on the achievements of its predecessor, a software analysis and visualization service launched in February 2025, this new offering standardizes analysis technology and design document generation know-how. In this service, Fujitsu proprietary technology leverages code analysis techniques on remaining design information and existing programs and manages RAG using Fujitsu Knowledge Graph–Enhanced RAG for Software Engineering. By linking large volumes of source code, it prevents omissions and hallucinations, and automatically generates highly accurate, easy-to-read design documentation.

This service reduces the time-consuming process of understanding programming languages and generating design documents, which previously required extensive human effort, by approximately 97%, even without expert knowledge. Furthermore, compared to analysis solely by general generative AI, Fujitsu’s proprietary technology generates consistent design information without omissions from existing system source code, even for complex COBOL language. This has improved comprehensiveness by 95%. These accuracy enhancements have also led to a 60% improvement in the readability of design documents compared to conventional methods, confirming the generation of high-quality design documents.

Moving forward, Fujitsu plans to begin offering support services for the introduction of this service. Additionally, beyond automatic design document generation, Fujitsu plans to sequentially introduce features for rebuilding existing source code for future use, automatically rewriting source code, and supporting operation and maintenance, starting in fiscal year 2026. Through this service, Fujitsu aims to generate high-quality design documents, enabling a clear understanding of current system specifications and characteristics, and strongly supporting the formulation and implementation of system modernization and migration strategies.

Toshihiro Horiuchi, Managing Executive Officer, SMBC Nikko Securities Inc. comments:
“We see this announcement as an initiative that realistically advances the modernization of our legacy systems by combining Fujitsu’s deep system development expertise built up over many years with generative AI. From fiscal year 2025, we have been conducting joint verification with Fujitsu on reverse-engineering design documentation for legacy languages, including COBOL, and through this collaboration we have come to recognize the significant potential of this technology. Going forward, we hope to continue working closely with Fujitsu to achieve more practical and effective modernization.”