diff --git a/src/test/modules/commit_ts/Makefile b/src/test/modules/commit_ts/Makefile
index 6d4f3be358e..6a9c3971fbc 100644
--- a/src/test/modules/commit_ts/Makefile
+++ b/src/test/modules/commit_ts/Makefile
@@ -2,6 +2,9 @@
 
 REGRESS = commit_timestamp
 REGRESS_OPTS = --temp-config=$(top_srcdir)/src/test/modules/commit_ts/commit_ts.conf
+# Disabled because these tests require "track_commit_timestamp = on",
+# which typical installcheck users do not have (e.g. buildfarm clients).
+NO_INSTALLCHECK = 1
 
 ifdef USE_PGXS
 PG_CONFIG = pg_config
diff --git a/src/test/modules/test_rls_hooks/Makefile b/src/test/modules/test_rls_hooks/Makefile
index 6b772c4db12..284fdaf0958 100644
--- a/src/test/modules/test_rls_hooks/Makefile
+++ b/src/test/modules/test_rls_hooks/Makefile
@@ -9,6 +9,9 @@ EXTENSION = test_rls_hooks
 
 REGRESS = test_rls_hooks
 REGRESS_OPTS = --temp-config=$(top_srcdir)/src/test/modules/test_rls_hooks/rls_hooks.conf
+# Disabled because these tests require "shared_preload_libraries=test_rls_hooks",
+# which typical installcheck users do not have (e.g. buildfarm clients).
+NO_INSTALLCHECK = 1
 
 ifdef USE_PGXS
 PG_CONFIG = pg_config