Mainframe Migration Tools: What They Do Well and Where They Fall Short

Mainframe migration tools fall into four broad categories: discovery and analysis, rehosting and emulation, automated code translation, and data migration — and most real programmes require tools from at least three of them. Vendor demos of automated COBOL-to-Java conversion often look impressive, but are typically run on cleaner code than what organisations actually have in production. While automated translation reliably produces runnable code, it rarely produces maintainable code, and bridging that gap is where the majority of migration budgets are spent. Discovery and analysis tools are considered the most consistently valuable category, as no organisation typically has a full picture of a system built up over decades. Buyers are also advised to scrutinise vendor ownership before signing long-term agreements, as consolidation through acquisition is common in this market.