diff --git a/scripts/build.sh b/scripts/build.sh
index 502cf1e..5cb70cb 100755
--- a/scripts/build.sh
+++ b/scripts/build.sh
@@ -19,6 +19,7 @@ then
 else
   echo "GH_TOKEN passed, doing an insiders build.."
   pip install git+https://${GH_TOKEN}@github.com/squidfunk/mkdocs-material-insiders.git
+  pip install pngquant
   ENABLE_PDF_EXPORT=1 mkdocs build -f mkdocs-insiders.yml
 
   # Put the PDF into secret location