diff --git a/manifests/grants/psql11.pp b/manifests/grants/psql11.pp
new file mode 100644
index 0000000..074a980
--- /dev/null
+++ b/manifests/grants/psql11.pp
@@ -0,0 +1,128 @@
+# @api private
+class pgprobackup::grants::psql11 (
+  String $db_name,
+  String $db_user
+) {
+  # GRANT USAGE ON SCHEMA pg_catalog TO backup;
+  postgresql::server::grant { "pg_catalog_usage_to_${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'USAGE',
+    object_type => 'SCHEMA',
+    object_name => 'pg_catalog',
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.current_setting(text) TO backup;
+  postgresql::server::grant { "current_setting-to-${db_user}":
+    db               => $db_name,
+    role             => $db_user,
+    privilege        => 'EXECUTE',
+    object_type      => 'FUNCTION',
+    object_name      => ['pg_catalog', 'current_setting'],
+    object_arguments => ['text'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.set_config(text, text, boolean) TO backup;
+  postgresql::server::grant { "current_setting-to-${db_user}":
+    db               => $db_name,
+    role             => $db_user,
+    privilege        => 'EXECUTE',
+    object_type      => 'FUNCTION',
+    object_name      => ['pg_catalog', 'set_config'],
+    object_arguments => ['text','text','boolean'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_is_in_recovery() TO backup;
+  postgresql::server::grant { "pg_is_in_recovery-to-${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'EXECUTE',
+    object_type => 'FUNCTION',
+    object_name => ['pg_catalog', 'pg_is_in_recovery'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_start_backup(text, boolean, boolean) TO backup;
+  postgresql::server::grant { "pg_start_backup-to-${db_user}":
+    db               => $db_name,
+    role             => $db_user,
+    privilege        => 'EXECUTE',
+    object_type      => 'FUNCTION',
+    object_name      => ['pg_catalog','pg_start_backup'],
+    object_arguments => ['text', 'boolean', 'boolean'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_stop_backup(boolean, boolean) TO backup;
+  postgresql::server::grant { "pg_stop_backup-to-${db_user}":
+    db               => $db_name,
+    role             => $db_user,
+    privilege        => 'EXECUTE',
+    object_type      => 'FUNCTION',
+    object_name      => ['pg_catalog','pg_stop_backup'],
+    object_arguments => ['boolean', 'boolean'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_create_restore_point(text) TO backup;
+  postgresql::server::grant { "pg_create_restore_point-to-${db_user}":
+    db               => $db_name,
+    role             => $db_user,
+    privilege        => 'EXECUTE',
+    object_type      => 'FUNCTION',
+    object_name      => ['pg_catalog','pg_create_restore_point'],
+    object_arguments => ['text'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_switch_wal() TO backup;
+  postgresql::server::grant { "pg_switch_wal-to-${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'EXECUTE',
+    object_type => 'FUNCTION',
+    object_name => ['pg_catalog','pg_switch_wal'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_last_wal_replay_lsn() TO backup;
+  postgresql::server::grant { "pg_last_wal_replay_lsn-to-${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'EXECUTE',
+    object_type => 'FUNCTION',
+    object_name => ['pg_catalog','pg_last_wal_replay_lsn'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.txid_current() TO backup;
+  postgresql::server::grant { "txid_current-to-${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'EXECUTE',
+    object_type => 'FUNCTION',
+    object_name => ['pg_catalog','txid_current'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.txid_current_snapshot() TO backup;
+  postgresql::server::grant { "txid_current_snapshot-to-${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'EXECUTE',
+    object_type => 'FUNCTION',
+    object_name => ['pg_catalog','txid_current_snapshot'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.txid_snapshot_xmax(txid_snapshot) TO backup;
+  postgresql::server::grant { "txid_snapshot_xmax-to-${db_user}":
+    db               => $db_name,
+    role             => $db_user,
+    privilege        => 'EXECUTE',
+    object_type      => 'FUNCTION',
+    object_name      => ['pg_catalog','txid_snapshot_xmax'],
+    object_arguments => ['txid_snapshot'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_control_checkpoint() TO backup;
+  postgresql::server::grant { "pg_control_checkpoint-to-${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'EXECUTE',
+    object_type => 'FUNCTION',
+    object_name => ['pg_catalog','pg_control_checkpoint'],
+  }
+}
diff --git a/manifests/grants/psql15.pp b/manifests/grants/psql15.pp
new file mode 100644
index 0000000..06fc13f
--- /dev/null
+++ b/manifests/grants/psql15.pp
@@ -0,0 +1,129 @@
+# @api private
+# @see https://postgrespro.com/docs/enterprise/15/app-pgprobackup
+class pgprobackup::grants::psql15 (
+  String $db_name,
+  String $db_user
+) {
+  # GRANT USAGE ON SCHEMA pg_catalog TO backup;
+  postgresql::server::grant { "pg_catalog_usage_to_${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'USAGE',
+    object_type => 'SCHEMA',
+    object_name => 'pg_catalog',
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.current_setting(text) TO backup;
+  postgresql::server::grant { "current_setting-to-${db_user}":
+    db               => $db_name,
+    role             => $db_user,
+    privilege        => 'EXECUTE',
+    object_type      => 'FUNCTION',
+    object_name      => ['pg_catalog', 'current_setting'],
+    object_arguments => ['text'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.set_config(text, text, boolean) TO backup;
+  postgresql::server::grant { "current_setting-to-${db_user}":
+    db               => $db_name,
+    role             => $db_user,
+    privilege        => 'EXECUTE',
+    object_type      => 'FUNCTION',
+    object_name      => ['pg_catalog', 'set_config'],
+    object_arguments => ['text','text','boolean'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_is_in_recovery() TO backup;
+  postgresql::server::grant { "pg_is_in_recovery-to-${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'EXECUTE',
+    object_type => 'FUNCTION',
+    object_name => ['pg_catalog', 'pg_is_in_recovery'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_backup_start(text, boolean) TO backup;
+  postgresql::server::grant { "pg_backup_start-to-${db_user}":
+    db               => $db_name,
+    role             => $db_user,
+    privilege        => 'EXECUTE',
+    object_type      => 'FUNCTION',
+    object_name      => ['pg_catalog','pg_backup_start'],
+    object_arguments => ['text', 'boolean'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_backup_stop(boolean) TO backup;
+  postgresql::server::grant { "pg_backup_stop-to-${db_user}":
+    db               => $db_name,
+    role             => $db_user,
+    privilege        => 'EXECUTE',
+    object_type      => 'FUNCTION',
+    object_name      => ['pg_catalog','pg_backup_stop'],
+    object_arguments => ['boolean'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_create_restore_point(text) TO backup;
+  postgresql::server::grant { "pg_create_restore_point-to-${db_user}":
+    db               => $db_name,
+    role             => $db_user,
+    privilege        => 'EXECUTE',
+    object_type      => 'FUNCTION',
+    object_name      => ['pg_catalog','pg_create_restore_point'],
+    object_arguments => ['text'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_switch_wal() TO backup;
+  postgresql::server::grant { "pg_switch_wal-to-${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'EXECUTE',
+    object_type => 'FUNCTION',
+    object_name => ['pg_catalog','pg_switch_wal'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_last_wal_replay_lsn() TO backup;
+  postgresql::server::grant { "pg_last_wal_replay_lsn-to-${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'EXECUTE',
+    object_type => 'FUNCTION',
+    object_name => ['pg_catalog','pg_last_wal_replay_lsn'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.txid_current() TO backup;
+  postgresql::server::grant { "txid_current-to-${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'EXECUTE',
+    object_type => 'FUNCTION',
+    object_name => ['pg_catalog','txid_current'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.txid_current_snapshot() TO backup;
+  postgresql::server::grant { "txid_current_snapshot-to-${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'EXECUTE',
+    object_type => 'FUNCTION',
+    object_name => ['pg_catalog','txid_current_snapshot'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.txid_snapshot_xmax(txid_snapshot) TO backup;
+  postgresql::server::grant { "txid_snapshot_xmax-to-${db_user}":
+    db               => $db_name,
+    role             => $db_user,
+    privilege        => 'EXECUTE',
+    object_type      => 'FUNCTION',
+    object_name      => ['pg_catalog','txid_snapshot_xmax'],
+    object_arguments => ['txid_snapshot'],
+  }
+
+  # GRANT EXECUTE ON FUNCTION pg_catalog.pg_control_checkpoint() TO backup;
+  postgresql::server::grant { "pg_control_checkpoint-to-${db_user}":
+    db          => $db_name,
+    role        => $db_user,
+    privilege   => 'EXECUTE',
+    object_type => 'FUNCTION',
+    object_name => ['pg_catalog','pg_control_checkpoint'],
+  }
+}
diff --git a/manifests/instance.pp b/manifests/instance.pp
index 1a21566..325b506 100644
--- a/manifests/instance.pp
+++ b/manifests/instance.pp
@@ -185,11 +185,32 @@
     }
 
     if $manage_grants {
-      # grants for postgresql 10 and newer
-      class { 'pgprobackup::grants::psql10':
-        db_name => $db_name,
-        db_user => $db_user,
-        require => Postgresql::Server::Database[$db_name],
+      case $version {
+        '9.6': {
+          fail("PostgreSQL ${version} not supported")
+        }
+        '10': {
+          class { 'pgprobackup::grants::psql10':
+            db_name => $db_name,
+            db_user => $db_user,
+            require => Postgresql::Server::Database[$db_name],
+          }
+        }
+        '11','12','13','14': {
+          class { 'pgprobackup::grants::psql11':
+            db_name => $db_name,
+            db_user => $db_user,
+            require => Postgresql::Server::Database[$db_name],
+          }
+        }
+        default: {
+          # grants for postgresql 15 and newer
+          class { 'pgprobackup::grants::psql15':
+            db_name => $db_name,
+            db_user => $db_user,
+            require => Postgresql::Server::Database[$db_name],
+          }
+        }
       }
     }
   }