diff --git a/.github/workflows/build_and_test.yml b/.github/workflows/build_and_test.yml
index 1764ddd8f..a07881dba 100644
--- a/.github/workflows/build_and_test.yml
+++ b/.github/workflows/build_and_test.yml
@@ -343,6 +343,8 @@ jobs:
             new_pg_major: 18
           - old_pg_major: 16
             new_pg_major: 18
+          - old_pg_major: 15
+            new_pg_major: 18
     env:
       old_pg_major: ${{ matrix.old_pg_major }}
       new_pg_major: ${{ matrix.new_pg_major }}
diff --git a/citus-tools b/citus-tools
deleted file mode 160000
index 3376bd684..000000000
--- a/citus-tools
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 3376bd6845f0614908ed304f5033bd644c82d3bf