AI Cut Our Research Time From 7 Days to 15 Minutes — Gareth Yoder, Vanguard
Vanguard reduced mainframe code research cycles from 7 days to 15 minutes via AI and MCP
“What used to take a mainframe engineer 7 days to dig into the code, analyze it, and come back with an answer, could now be done with an AI prompt.”
Vanguard's cash program technical lead describes how exposing a legacy mainframe codebase to AI tools via an MCP server collapsed code analysis feedback loops from 7 days to 15 minutes. The shift was a turning point in a large-scale parallel modernization effort involving data, producer, and consumer migration. This is a concrete, quantified enterprise case study for AI-assisted legacy system modernization at scale.