Modernizing Java Applications with IBM Bob

2026-02-19 · Source: Niklas Heidloff · Field: Technology & Digital — Software Development & Engineering, Artificial Intelligence & Machine Learning, Cloud Computing & IT Infrastructure · Depth: Intermediate, quick

Summary

IBM Bob, an AI-based engineering tool, facilitates the modernization of legacy Java applications, specifically converting WebSphere applications to OpenLiberty with updated Java runtimes. This process addresses traditional challenges in large-scale modernization projects, which are often time-consuming and difficult. Bob leverages autonomous AI agents to generate, adapt, and refine code iteratively, allowing developers to define intent and exit criteria while the agents handle complex refactorings and architectural updates. The tool integrates proactive insights and autonomous code generation into the development workflow, accelerating modernization efforts while ensuring developers maintain full oversight. It also supports understanding legacy systems, planning migrations, and executing modernization tasks efficiently, including generating server.xml and Containerfiles, and performing rule-based and AI-driven code changes.

Key takeaway

For AI Engineers tasked with modernizing legacy Java applications, consider integrating AI-driven tools like IBM Bob into your workflow. This approach can significantly reduce the manual effort involved in complex refactorings and architecture updates, allowing your team to focus on defining clear intent and validation criteria. You should explore Bob's capabilities for replatforming to cloud-native frameworks like OpenLiberty and automating Java runtime upgrades to accelerate project timelines.

Key insights

AI agents can autonomously modernize complex legacy Java applications, reducing manual effort while retaining developer control.

Principles

• Combine rule-based and AI-driven changes for modernization.
• Developers define intent and exit criteria for AI agents.

Method

IBM Bob analyzes legacy Java applications, generates configuration files (e.g., server.xml, Containerfile), applies rule-based changes, and then uses AI agents to address complex refactorings and update Java runtimes, iterating until successful.

In practice

• Convert WebSphere applications to OpenLiberty.
• Automate Java runtime upgrades.
• Generate documentation and diagrams for modernized code.

Topics

• IBM Bob
• Java Application Modernization
• AI Agents
• OpenLiberty
• Code Refactoring

Code references

• IBM/application-modernization-javaee-quarkus

Best for: Software Engineer, AI Engineer, DevOps Engineer

Related on AIssential

• IBM's AI coding 'partner' Bob hits general availability — IBM's Bob AI coding partner leverages diverse LLMs to boost developer productivity across the full software development lifecycle.
• Reimagining API modernization with deterministic AI-assisted engineering — AI-assisted, instruction-driven frameworks accelerate legacy API modernization by codifying patterns and ensuring deterministic outcomes.
• Former Palantir employees raise $60M for AI enterprise startup Conduct — AI agents require legible, operable enterprise systems to deliver results, especially with opaque legacy ERPs.
• Developing Documentation MCP Servers for IBM Bob — MCP servers provide AI agents with current, precise documentation access via structured search and virtual file system tools.
• Spec-driven Development with IBM Bob — Spec-driven Development (SDD) balances AI autonomy with human control for enterprise-grade software quality.
• ScarfBench: Benchmarking AI Agents for Enterprise Java Framework Migration — AI agents struggle with enterprise Java framework migration, achieving low behavioral success due to complex dependency management.

Open in AIssential →

Editorial summary, takeaway, and curation by AIssential. Original article published by Niklas Heidloff.