openrewrite/rewrite ? reverse-engineered prompt

Build me an open source code refactoring tool that can automatically update source code in a safe, repeatable way.

It should help with common things like framework migrations, security fixes, and style cleanup, so a user can point it at a repository and have it make the changes for them instead of doing everything by hand. I’d like it to support Java well, and also have a path for other popular languages like Kotlin, Groovy, JavaScript, Python, and C Sharp. For Java projects, it should be easy to run against either Gradle or Maven builds.

Make the refactoring rules easy to customize, and let people add their own reusable recipes too. Focus on being fast, accurate, and deterministic, so the same input gives the same output every time. If you need to look up current docs or best practices while building it, go ahead. Include solid tests and enough documentation that someone can understand how to run and extend it.