Accelerating AS/400 business rule extraction with Kiro: Step-by-step guide

This article demonstrates how Kiro, an agentic AI-powered development environment, accelerates AS/400 business rule extraction from legacy RPG and COBOL systems, compressing a traditionally 4-6 week manual process into 3 days.

• Kiro autonomously analyzes RPG/COBOL programs and DDS definitions to extract embedded business rules with code context and pseudocode equivalents
• Steering files provide persistent analysis instructions (naming conventions, standards) that apply across multiple sessions without reconfiguration
• Specs define discrete, actionable tasks executed autonomously with progress tracking for comprehensive documentation generation
• Produces business rules catalog, DDS field mappings, file dependencies, inter-program parameter documentation, and integration specifications
• Measured results: 70-85% reduction in effort (12 vs 40-80 person-hours) and ~90% timeline reduction for a 5-program, 40,000-line system
• Setup cost (templates, steering, specs) is one-time; per-system effort approximately 10 hours after initial configuration
• AI-extracted rules require validation by AS/400 subject matter experts before acting on modernization decisions

Kiro enables organizations to extract critical business logic from legacy AS/400 systems efficiently, freeing teams to focus on modernization strategy rather than manual code analysis.