diff --git a/.travis.yml b/.travis.yml
index f1c37d7..00d5cc6 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -333,6 +333,7 @@ install:
   - git submodule init libs/assert
   - git submodule init libs/config
   - git submodule init libs/core
+  - git submodule init libs/io
   - git submodule init libs/preprocessor
   - git submodule init libs/static_assert
   - git submodule init libs/throw_exception
diff --git a/appveyor.yml b/appveyor.yml
index 2ca7062..a3c2173 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -66,6 +66,7 @@ install:
   - git submodule init libs/assert
   - git submodule init libs/config
   - git submodule init libs/core
+  - git submodule init libs/io
   - git submodule init libs/preprocessor
   - git submodule init libs/static_assert
   - git submodule init libs/throw_exception