diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index f05773a..9d5738f 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -14,12 +14,9 @@ jobs:
   Test:
     strategy:
       matrix:
-        # pg_version: [15]
-        pg_version: [11, 12, 13, 14, 15]
+        pg_version: [13, 14, 15, 16, 17, 18]
         os: [ubuntu-22.04]
-        # tests: [tap]
         tests: [tap, python]
-        # test_mode: [normal, legacy, paranoia]
         test_mode: [normal, paranoia]
         exclude:
           - tests: tap
@@ -56,6 +53,11 @@ jobs:
       - name: Apply ptrack patches
         run: make patch top_builddir=../postgres
         working-directory: ptrack
+      - name: Apply probackup patch
+        if: ${{ matrix.pg_version == '18' }}
+        run: git apply ../pg_probackup/patches/REL_18_STABLE_pg_probackup.patch
+        working-directory: postgres
+        shell: bash {0}
       - name: Install Postgres
         run: |
           make install-postgres top_builddir=$GITHUB_WORKSPACE/postgres prefix=$HOME/pgsql &&
diff --git a/Makefile b/Makefile
index 499067a..9d4b451 100644
--- a/Makefile
+++ b/Makefile
@@ -22,6 +22,7 @@ ifdef USE_PGXS
 PGXS := $(shell $(PG_CONFIG) --pgxs)
 include $(PGXS)
 else
+subdir = contrib/ptrack
 top_builddir = ../..
 # Makefile.global is a build artifact and initially may not be available
 ifneq ($(wildcard $(top_builddir)/src/Makefile.global), )
diff --git a/t/001_basic.pl b/t/001_basic.pl
index 369a59c..907515e 100644
--- a/t/001_basic.pl
+++ b/t/001_basic.pl
@@ -117,9 +117,9 @@ BEGIN
 
 # Remember ptrack init_lsn
 my $init_lsn = $node->safe_psql("postgres", "SELECT ptrack_init_lsn()");
-unlike(
+like(
 	$init_lsn,
-	qr/0\/0/,
+	qr/0\/[0-9A-F][0-9A-F]+/,
 	'ptrack init LSN should not be 0/0 after CHECKPOINT');
 
 # Ptrack map should survive crash
@@ -161,9 +161,9 @@ BEGIN
 
 $node->safe_psql("postgres", "CHECKPOINT");
 $res_stdout = $node->safe_psql("postgres", "SELECT ptrack_init_lsn()");
-unlike(
+like(
 	$res_stdout,
-	qr/0\/0/,
+	qr/0\/[0-9A-F][0-9A-F]+/,
 	'ptrack init LSN should not be 0/0 after CHECKPOINT');
 ok($res_stdout ne $init_lsn, 'ptrack init_lsn should not be the same after map resize');
 $res_stdout = $node->safe_psql("postgres", "SELECT ptrack_get_pagemapset('$flush_lsn')");