Paper Summary - An Agile Approach to a Legacy System

- Sep 10 2019 -

I recently read an interesting paper, “An Agile Approach to a Legacy System”[1], on how to migrate legacy systems. One statement resonated with me: > The drive for the original rewrite came from development management and developers not business and users.

I have been involved in two major refactoring which was initiated by Engineers. One barely successful and the other a semi failure. It is easy to get excited about a rewrite to improve performance or because the code is messy to deal with. One hardly thinks about the business use case for such.

The author describes how and why they approached migrating a legacy system and what should be the motivation for such. In the narration he provided a few rule of thumbs that were interesting. I have listed them below for convenience:

A few things like “Treat politics as a user requirement” is thought provoking. But other things like “Don’t get hung up on process” and “Build a small, self-selected team” resonates to what others have said.

I would recommend reading it even if you don’t have to rewrite legacy systems. A very short read and full of wisdom.


  1. http://cdn.pols.co.uk/papers/agile-approach-to-legacy-systems.pdf