diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 856d99ee5ced935323171875ea173976d5c31c30..2a96a107b8e98caae48f00066a30d8e392e1fec6 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,7 +1,7 @@
 variables:
   _R_CHECK_CRAN_INCOMING_: "true"
   _R_CHECK_FORCE_SUGGESTS_: "true"
-  APT_PKGS: "libcurl4-openssl-dev"
+  APT_PKGS: c("libcurl4-openssl-dev", "libxext-dev")
 
 image: rocker/tidyverse