Gojekyll doesn't include an extensible plugin system¹.
The functionality of some plugins is built into the core program:
| Plugin | Motivation | Implementation Status | Missing Features |
|---|---|---|---|
| jekyll-avatar | GitHub Pages² | ✓ | |
| jekyll-coffeescript | GitHub Pages | ||
| jekyll-default-layout | GitHub Pages | ✓ | |
| jekyll-feed | GitHub Pages | ✓ | |
| jekyll-gist | core³ | ✓ | noscript option |
| jekyll-github-metadata | GitHub Pages | partial | contributors, public_repositories, show_downloads, releases, versions, wiki_url; Octokit configuration; GitHub Enterprise |
| jekyll-live-reload | core | ✓ | always enabled (by design); no way to disable |
| jekyll-mentions | GitHub Pages | ✓ | |
| jekyll-optional-front-matter | GitHub Pages | ||
| jekyll-paginate | core | ||
| jekyll-readme-index | GitHub Pages | ||
| jekyll-redirect_from | GitHub Pages | ✓ | user template |
| jekyll-relative-links | GitHub Pages | ✓ | |
| jekyll-sass-converter | core | ✓ | always enabled (by design); no way to disable |
| jekyll-seo_tag | GitHub Pages | partial | dateModified, datePublished, publisher, mainEntityOfPage, @type |
| jekyll-sitemap | GitHub Pages | ✓ | file modified dates⁴ |
| jekyll-titles-from-headings | GitHub Pages | ||
| jemoji | GitHub Pages | ✓ | image tag fallback |
| GitHub pages | GitHub Pages | ✓ | The plugins that github-pages includes are in various stages of implementation, listed above |
¹ (1) The code and internal APIs are too immature for this; and (2) the natural way of implementing this only works on Linux.
² https://pages.github.com/versions/
³ “Core” plugins are referenced in the main Jekyll documentation.
The Official Plugins section of the Jekyll documentation, and the #Official tag of Awesome Jekyll Plugins, look dated; I didn't use those.
⁴ These don't seem that useful with source control and CI. (Post dates are included.)