Polyglot is a Ruby gem that serves as a Jekyll plugin for internationalization (i18n) of static sites. It enables building a site in multiple languages by forking the Jekyll build process per language, patching core Jekyll classes (`Site`, `StaticFile`) to handle language-specific files, and providing Liquid tags for SEO headers (`I18n_Headers`) and URL relativization control (`static_href`). The plugin coordinates documents across languages, supports fallback to the default language, localizes `site.data` via language-specific subdirectories, and generates Netlify-compatible redirects. It is not a standalone application but a library that integrates deeply with Jekyll via hooks and monkey-patching. The repository includes a comprehensive demo site with 18 languages, a full RSpec test suite, CI via CircleCI, and extensive documentation in both README and `ai_docs/`. The codebase is well-structured, with clear separation of concerns (hooks, patches, liquid tags), and demonstrates non-trivial engineering in areas like parallel forking, regex-based URL relativization, and document coordination.