diff --git a/.ci/gitlab/config.yml b/.ci/gitlab/config.yml
index 451d2c27650d823040f9dd49c3afce604b1be64f..370689d0052b4ef55653275dd88d1ead0cc6fdae 100644
--- a/.ci/gitlab/config.yml
+++ b/.ci/gitlab/config.yml
@@ -135,7 +135,7 @@ unstable_gcc_full cpp:
     extends: .subdir-test
     variables:
         CI_IMAGE: debian-unstable_gcc_full
-        TESTS_MODULE_SUBDIR: None
+        TESTS_MODULE_SUBDIR: gdt
     tags:
         - dustin
     stage: cpp
@@ -147,7 +147,7 @@ unstable_gcc_full headercheck:
     extends: .subdir-test
     variables:
         CI_IMAGE: debian-unstable_gcc_full
-        TESTS_MODULE_SUBDIR: None
+        TESTS_MODULE_SUBDIR: gdt
     tags:
         - dustin
     stage: headercheck
@@ -159,7 +159,7 @@ gcc_full cpp:
     extends: .subdir-test
     variables:
         CI_IMAGE: debian_gcc_full
-        TESTS_MODULE_SUBDIR: None
+        TESTS_MODULE_SUBDIR: gdt
     tags:
         - dustin
     stage: cpp
@@ -171,7 +171,7 @@ gcc_full headercheck:
     extends: .subdir-test
     variables:
         CI_IMAGE: debian_gcc_full
-        TESTS_MODULE_SUBDIR: None
+        TESTS_MODULE_SUBDIR: gdt
     tags:
         - dustin
     stage: headercheck
@@ -183,7 +183,7 @@ clang_full cpp:
     extends: .subdir-test
     variables:
         CI_IMAGE: debian_clang_full
-        TESTS_MODULE_SUBDIR: None
+        TESTS_MODULE_SUBDIR: gdt
     stage: cpp
     needs: ["debian_clang_full"]
     script:
@@ -193,7 +193,7 @@ clang_full headercheck:
     extends: .subdir-test
     variables:
         CI_IMAGE: debian_clang_full
-        TESTS_MODULE_SUBDIR: None
+        TESTS_MODULE_SUBDIR: gdt
     stage: headercheck
     needs: ["debian_clang_full"]
     script:
diff --git a/.ci/gitlab/config_template.py b/.ci/gitlab/config_template.py
index c7465483d3f2832f177a3dc41965ba53b3eb6d70..cc8b07835423071d49bcb95e0857c6fd15773545 100755
--- a/.ci/gitlab/config_template.py
+++ b/.ci/gitlab/config_template.py
@@ -165,7 +165,7 @@ lint:
 
 tpl = jinja2.Template(tpl)
 images = ['debian-unstable_gcc_full', 'debian_gcc_full', 'debian_clang_full']
-subdirs = [None]
+subdirs = ['gdt']
 kinds = ['cpp', 'headercheck']
 matrix = product(images, subdirs, kinds)
 with open(os.path.join(os.path.dirname(__file__), 'config.yml'), 'wt') as yml:
diff --git a/.ci/shared b/.ci/shared
index b81e4900992b4e32457247403f0462ae255ec15c..8e5391465a1c9581bf4fa2915d91aa103c89a0db 160000
--- a/.ci/shared
+++ b/.ci/shared
@@ -1 +1 @@
-Subproject commit b81e4900992b4e32457247403f0462ae255ec15c
+Subproject commit 8e5391465a1c9581bf4fa2915d91aa103c89a0db