Migration Paths

Our research covers 36 distinct migration paths spanning mainframe modernization, cloud replatforming, database migrations, language conversions, and infrastructure transitions. Each path includes an editorial scoping cost range, a typical timeline, and a complexity assessment that reflects team size and codebase scope. Where available, we include ROI timelines and cost avoidance figures that procurement teams can use as starting points in business case development. These are scoping ranges, not supplier quotes or measured project medians.

The migrations are organized by hub category (thematic groupings such as mainframe modernization, cloud migration, and database modernization), so that teams evaluating adjacent paths can compare trade-offs side by side. For example, an organization considering moving off a mainframe can compare COBOL-to-C#, COBOL-to-Java, and mainframe-to-cloud rehosting paths within the same hub, each with its own cost range and timeline. This structure reflects how modernization decisions are actually made: not in isolation, but as a choice among competing approaches with different risk, cost, and timeline profiles.

Every migration path is reviewed against a standard framework that includes decision criteria (when to pursue the path and when not to), alternative approaches, AI-assisted tooling options, vendor landscape analysis, and evaluation questions for RFP processes. The goal is to provide the kind of structured, comparable data that engineering leaders and procurement teams need to make informed decisions, replacing anecdotal vendor claims with source-backed intelligence. Cost and timeline figures are presented as ranges rather than point estimates to reflect the inherent variability across organizations of different sizes, industries, and technical maturity levels.

Paths are updated on a rolling basis as new case studies and vendor disclosures become available. Each path notes its last review date, so readers can assess recency independently. Project counts, median costs, and success rates published in earlier versions of this index could not be reproduced from available records and have been withdrawn; see our methodology. We prioritize depth over breadth: every migration included here is one we can support with sourced, actionable guidance, rather than speculative coverage of emerging paths without track records.