diff --git a/appveyor.yml b/appveyor.yml
index 7d45ec5..3b93a22 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,5 +1,7 @@
 version: 1.16.{build}.0
 image: Visual Studio 2017
+install:
+- cmd: git submodule -q update --init
 build_script:
 - ps: .\build.ps1 -configuration release
 after_build: