diff --git a/doc/guides/getting_started/book.toml b/doc/guides/getting_started/book.toml
index 7bbc08b..119fd08 100644
--- a/doc/guides/getting_started/book.toml
+++ b/doc/guides/getting_started/book.toml
@@ -15,5 +15,8 @@
 edit-url-template = "https://github.com/lowrisc/opentitan/edit/master/doc/guides/getting_started/{path}"
 curly-quotes = true
 
+[preprocessor.readme2index]
+command = "../../../util/mdbook_readme2index.py"
+
 [preprocessor.toolversion]
 command = "../../../util/mdbook_toolversion.py"
diff --git a/util/site/build-docs.sh b/util/site/build-docs.sh
index e152f8d..8522dd4 100755
--- a/util/site/build-docs.sh
+++ b/util/site/build-docs.sh
@@ -132,6 +132,7 @@
 # ./doc/guides/getting_started/book.toml
 book_guides_env="env"
 book_guides_env+=" MDBOOK_PREPROCESSOR__TOOLVERSION__COMMAND=${proj_root}/util/mdbook_toolversion.py"
+book_guides_env+=" MDBOOK_PREPROCESSOR__README2INDEX__COMMAND=${proj_root}/util/mdbook_readme2index.py"
 
 # Build up Hugo arguments
 hugo_args=""