diff --git a/README.org b/README.org
index 834de388dcd17d7c032c9063eafb3dbcf3cca724..5f38dd62771020cf9f218843cadd721f2b8b73e2 100644
--- a/README.org
+++ b/README.org
@@ -37,6 +37,10 @@ improvements that can be done here.
   #+BEGIN_SRC sh
     git clone https://gitlab.emacsos.com/sylecn/libpyzy.git
     cd libpyzy/src/
+    # Side note: zero-pinyin-service must be in libpyzy src dir to build, because
+    # it uses the source code directly. I didn't use libpyzy as a dependency
+    # because I have done code review and patched the libpyzy code and those
+    # changes are not sent to upstream. libpyzy is pretty inactive these days.
     git clone https://gitlab.emacsos.com/sylecn/zero-pinyin-service.git
     cd zero-pinyin-service/
     meson setup release/