diff --git a/README.md b/README.md
index 7d94096..c5ef8e0 100644
--- a/README.md
+++ b/README.md
@@ -64,6 +64,7 @@ To build the documents, you need `asciidoc`
 ### To build
 
 ```bash
+$ git submodule update --init --recursive
 $ meson --buildtype=release . build
 $ ninja -C build
 ```