diff --git a/.github/workflows/build-docs.yml b/.github/workflows/build-docs.yml
index 89c662db..1b692fed 100644
--- a/.github/workflows/build-docs.yml
+++ b/.github/workflows/build-docs.yml
@@ -16,7 +16,7 @@ jobs:
       run: |
           sudo apt-get update
           sudo apt-get install asciidoctor ruby-pygments.rb -y
-          asciidoctor -t -v -D docs/smith --backend=xhtml5 -n -a toc=left -a source-hightlighter-pygments -o index.html docs/smith/manual.adoc
+          asciidoctor -t -v -D docs/smith --backend=xhtml5 -n -a toc=left -a source-hightlighter=pygments -o index.html docs/smith/manual.adoc
     - name: Deploy docs to gh-pages
       uses: peaceiris/actions-gh-pages@v4
       with:
diff --git a/docs/smith/manual.adoc b/docs/smith/manual.adoc
index 432b088a..69dfe8c4 100644
--- a/docs/smith/manual.adoc
+++ b/docs/smith/manual.adoc
@@ -4,11 +4,11 @@
 :keywords: fonts, building, testing, releasing, writing systems
 
 :toc: left
-
 :toclevels: 2
 :sectanchors:
 :sectlinks:
 :sectnums:
+:source-highlighter: pygments
 
 include::intro.adoc[]