About ShiftKit
ShiftKit is a focused set of AST-based config converters for the JavaScript ecosystem. One tool per migration. Each runs entirely in your browser.
What it is
A converter takes a config you already have (a jest.config.js, an .eslintrc, a webpack.config.js) and produces an equivalent config for a newer tool, with explicit notes about anything that does not map cleanly. The parsing happens in your browser via Babel; nothing is uploaded.
What it isn’t
It is not a codemod for your test bodies or source files. For those, use a tool like @vitest/migrate. ShiftKit’s scope is config - the place where most migrations actually get stuck.
How it’s built
Each converter lives in its own Apache-2.0-licensed npm package so you can run it from CI without the website. The flagship is @shiftkit/jest-to-vitest, with @shiftkit/webpack-to-vite now in beta. Source on GitHub.