Documentation
Contributing to the documentation is simple. The files are hosted on https://github.com/pieceofcake2/docs, in the 2.x branch. Feel free to fork the repo, add your changes/improvements/translations and give back by opening a pull request. You can even edit the docs online with GitHub, without ever downloading the files: the "Edit this page on GitHub" link at the bottom of every page will direct you to GitHub's online editor for that page.
The documentation is written in Markdown, in English and Japanese, and built with VitePress. Changes merged into the 2.x branch are deployed to https://pieceofcake2.github.io/docs/ automatically by GitHub Actions.
How to preview your changes locally, the layout of the repository, the guidelines for translations and the formatting guide (headings and anchors, links, code samples, alerts, change notes for the fork) are described in the README of the docs repository.
