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Austin Powell

Austin Powell is passionate about making people's lives easier through technology and helping teams move forward. Throughout his career, he's guided organizations through technically complex transitions across the full .NET stack with front-end depth in Angular, Vue, and React. He's also well versed in using AI to accelerate delivery. A lifelong learner and tinkerer with an unquenchable curiosity, Austin brings a keen eye for detail and a craftsman's mindset to every engagement. He lives in Kansas City with his wife Chelsea and their two children.

Header image for a Keyhole Software article by Austin Powell about using LLMs and AI-assisted discovery to understand, document, and modernize a legacy Delphi application. The image highlights transforming a "black box" system into a documented architecture blueprint and delivering a modernization project in approximately half the original timeline.

How We Used LLMs to Understand and Modernize a Legacy Delphi Application

Austin Powell .NET, Agentic AI & AI-Accelerated Development, All Industries, Articles, Artificial Intelligence, Modernization Leave a Comment

Many legacy modernization projects start with a simple question: what does this thing actually do?

In this project, we were modernizing a decades-old Delphi application with limited documentation, no meaningful test coverage, engineers long since moved on, and significant unknowns about the environment in which it operated.

Modernizing legacy systems is challenging, particularly when documentation is limited and system knowledge has been lost over time. When LLMs and AI are applied thoughtfully, they can help teams understand legacy systems faster and reduce modernization risk.

This article focuses on how we used LLMs to understand, document, and de-risk an unfamiliar legacy system before modernization began. Once the application was understood and the architecture was defined, the team leveraged AI-assisted development workflows to accelerate the Delphi-to-.NET rewrite itself. Evan Sanning shares that side of the project in his companion article, How We Used LLMs to Rewrite a Legacy Delphi Application in C#.