diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 30f703c..c04838e 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -39,7 +39,7 @@ build:
                 - env DESTDIR=$BUILD_DIR make install 
                 - popd
                 - pushd parts/mosquitto-go-auth 
-                - export CGO_CFLAGS="-I$BUILD_DIR/opt -fPIC"
+                - export CGO_CFLAGS="-I$BUILD_DIR/opt/include -fPIC"
                 - export CGO_LDFLAGS="-shared"
                 - make
                 - cp go-auth.so $BUILD_DIR/opt/lib