diff --git a/.github/workflows/jekyll-gh-pages.yml b/.github/workflows/jekyll-gh-pages.yml
index 6552061..a0ca5b9 100644
--- a/.github/workflows/jekyll-gh-pages.yml
+++ b/.github/workflows/jekyll-gh-pages.yml
@@ -27,6 +27,7 @@ jobs:
         run: |
           pip install mkdocs
           pip install mkdocs-material
+          pip install mkdocs-mermaid2-plugin
       - name: Build
         run: |
           mkdocs build