diff --git a/openpilot/starpilot/car/ford/rear_fog.py b/openpilot/starpilot/car/ford/rear_fog.py
index 2a907b2f9f..07577bea81 100644
--- a/openpilot/starpilot/car/ford/rear_fog.py
+++ b/openpilot/starpilot/car/ford/rear_fog.py
@@ -5,7 +5,7 @@ MAX_AGE_NS = 1_500_000_000
 
 
 def boot_time_ns():
-  return time.clock_gettime_ns(time.CLOCK_BOOTTIME)
+  return time.clock_gettime_ns(getattr(time, "CLOCK_BOOTTIME", time.CLOCK_MONOTONIC))
 
 
 def main_bus(cp):
diff --git a/openpilot/starpilot/ui/tests/test_ford_rear_fog.py b/openpilot/starpilot/ui/tests/test_ford_rear_fog.py
index 5b8787c5db..1814246307 100644
--- a/openpilot/starpilot/ui/tests/test_ford_rear_fog.py
+++ b/openpilot/starpilot/ui/tests/test_ford_rear_fog.py
@@ -223,3 +223,12 @@ def test_runtime_snapshot_wires_receive_only_status():
   session.adapter.ui_state.started = False
   session.snapshot(ShellMode.ONROAD)
   assert session.rear_fog.sample.call_args.kwargs == {"active": False}
+
+
+
+def test_boot_clock_matches_native_mac_fallback(monkeypatch):
+  monkeypatch.delattr(rear_fog.time, "CLOCK_BOOTTIME", raising=False)
+  clock = Mock(return_value=10_000_000_000)
+  monkeypatch.setattr(rear_fog.time, "clock_gettime_ns", clock)
+  assert rear_fog.boot_time_ns() == 10_000_000_000
+  clock.assert_called_once_with(rear_fog.time.CLOCK_MONOTONIC)
diff --git a/prebuilt.json b/prebuilt.json
index d327dc21d0..c221c39eda 100644
--- a/prebuilt.json
+++ b/prebuilt.json
@@ -1 +1 @@
-{"protected_inventory_sha256": "de797337075c26ae5df34af444587f27cc5ce06022c059568f9c188d7c18bfc0", "schema_version": 1}
+{"protected_inventory_sha256": "8217ee78dde766571a47c49219cafb5054495760c10e2d557e8e22bc7bd89528", "schema_version": 1}