diff --git a/salt/salt/prometheus/exporters/postgres_exporter.sls b/salt/salt/prometheus/exporters/postgres_exporter.sls
index 4244164..9c22869 100644
--- a/salt/salt/prometheus/exporters/postgres_exporter.sls
+++ b/salt/salt/prometheus/exporters/postgres_exporter.sls
@@ -16,6 +16,13 @@ unpack-postgres-exporter:
     - options: --strip-components=1
     - enforce_toplevel: False
 
+/opt/prometheus_postgres_exporter/queries.yaml:
+  file.managed:
+    - source: salt://prometheus/exporters/queries.yaml
+    - user: postgres
+    - group: postgres
+    - mode: 644
+
 /etc/systemd/system/prometheus_postgres_exporter.service:
   file.managed:
     - source: salt://prometheus/exporters/prometheus_postgres_exporter.service
diff --git a/salt/salt/prometheus/exporters/prometheus_postgres_exporter.service b/salt/salt/prometheus/exporters/prometheus_postgres_exporter.service
index 7d7b861..21d362a 100644
--- a/salt/salt/prometheus/exporters/prometheus_postgres_exporter.service
+++ b/salt/salt/prometheus/exporters/prometheus_postgres_exporter.service
@@ -9,6 +9,7 @@ WorkingDirectory=/opt/prometheus_postgres_exporter
 User=postgres
 Group=postgres
 Environment="DATA_SOURCE_NAME=user=postgres host=/run/postgresql/ sslmode=disable"
+Environment="PG_EXPORTER_EXTEND_QUERY_PATH=/opt/prometheus_postgres_exporter/queries.yaml"
 ExecStart=/opt/prometheus_postgres_exporter/postgres_exporter
 
 [Install]
diff --git a/salt/salt/prometheus/exporters/queries.yaml b/salt/salt/prometheus/exporters/queries.yaml
new file mode 100644
index 0000000..309b9b1
--- /dev/null
+++ b/salt/salt/prometheus/exporters/queries.yaml
@@ -0,0 +1,6 @@
+pg_txid:
+  query: "SELECT max(age(datfrozenxid)) AS max_txid_age from pg_database"
+  metrics:
+    - max_txid_age:
+        usage: "GAUGE"
+        description: "Highest transaction ID age (wraparound at 2 billion)"