diff --git a/selfdrive/car/body/carcontroller.py b/selfdrive/car/body/carcontroller.py
index db34320caa..259126c416 100644
--- a/selfdrive/car/body/carcontroller.py
+++ b/selfdrive/car/body/carcontroller.py
@@ -75,7 +75,7 @@ class CarController(CarControllerBase):
     can_sends = []
     can_sends.append(bodycan.create_control(self.packer, torque_l, torque_r))
 
-    new_actuators = CC.actuators.copy()
+    new_actuators = CC.actuators.as_builder()
     new_actuators.accel = torque_l
     new_actuators.steer = torque_r
     new_actuators.steerOutputCan = torque_r
diff --git a/selfdrive/car/chrysler/carcontroller.py b/selfdrive/car/chrysler/carcontroller.py
index 39248f3f75..85f53f68eb 100644
--- a/selfdrive/car/chrysler/carcontroller.py
+++ b/selfdrive/car/chrysler/carcontroller.py
@@ -78,7 +78,7 @@ class CarController(CarControllerBase):
 
     self.frame += 1
 
-    new_actuators = CC.actuators.copy()
+    new_actuators = CC.actuators.as_builder()
     new_actuators.steer = self.apply_steer_last / self.params.STEER_MAX
     new_actuators.steerOutputCan = self.apply_steer_last
 
diff --git a/selfdrive/car/ford/carcontroller.py b/selfdrive/car/ford/carcontroller.py
index 47082fb56f..7be3b2ebe9 100644
--- a/selfdrive/car/ford/carcontroller.py
+++ b/selfdrive/car/ford/carcontroller.py
@@ -113,7 +113,7 @@ class CarController(CarControllerBase):
     self.steer_alert_last = steer_alert
     self.lead_distance_bars_last = hud_control.leadDistanceBars
 
-    new_actuators = actuators.copy()
+    new_actuators = actuators.as_builder()
     new_actuators.curvature = self.apply_curvature_last
 
     self.frame += 1
diff --git a/selfdrive/car/gm/carcontroller.py b/selfdrive/car/gm/carcontroller.py
index f8d747029b..b204d3b80f 100644
--- a/selfdrive/car/gm/carcontroller.py
+++ b/selfdrive/car/gm/carcontroller.py
@@ -155,7 +155,7 @@ class CarController(CarControllerBase):
       if self.frame % 10 == 0:
         can_sends.append(gmcan.create_pscm_status(self.packer_pt, CanBus.CAMERA, CS.pscm_status))
 
-    new_actuators = actuators.copy()
+    new_actuators = actuators.as_builder()
     new_actuators.steer = self.apply_steer_last / self.params.STEER_MAX
     new_actuators.steerOutputCan = self.apply_steer_last
     new_actuators.gas = self.apply_gas
diff --git a/selfdrive/car/hyundai/carcontroller.py b/selfdrive/car/hyundai/carcontroller.py
index 7829d764b0..4038ddcca9 100644
--- a/selfdrive/car/hyundai/carcontroller.py
+++ b/selfdrive/car/hyundai/carcontroller.py
@@ -163,7 +163,7 @@ class CarController(CarControllerBase):
       if self.frame % 50 == 0 and self.CP.openpilotLongitudinalControl:
         can_sends.append(hyundaican.create_frt_radar_opt(self.packer))
 
-    new_actuators = actuators.copy()
+    new_actuators = actuators.as_builder()
     new_actuators.steer = apply_steer / self.params.STEER_MAX
     new_actuators.steerOutputCan = apply_steer
     new_actuators.accel = accel
diff --git a/selfdrive/car/mazda/carcontroller.py b/selfdrive/car/mazda/carcontroller.py
index 8d3a59b4ea..3d41634879 100644
--- a/selfdrive/car/mazda/carcontroller.py
+++ b/selfdrive/car/mazda/carcontroller.py
@@ -58,7 +58,7 @@ class CarController(CarControllerBase):
     can_sends.append(mazdacan.create_steering_control(self.packer, self.CP,
                                                       self.frame, apply_steer, CS.cam_lkas))
 
-    new_actuators = CC.actuators.copy()
+    new_actuators = CC.actuators.as_builder()
     new_actuators.steer = apply_steer / CarControllerParams.STEER_MAX
     new_actuators.steerOutputCan = apply_steer
 
diff --git a/selfdrive/car/mock/carcontroller.py b/selfdrive/car/mock/carcontroller.py
index 2b2da954ff..0cd37c0369 100644
--- a/selfdrive/car/mock/carcontroller.py
+++ b/selfdrive/car/mock/carcontroller.py
@@ -2,4 +2,4 @@ from openpilot.selfdrive.car.interfaces import CarControllerBase
 
 class CarController(CarControllerBase):
   def update(self, CC, CS, now_nanos):
-    return CC.actuators.copy(), []
+    return CC.actuators.as_builder(), []
diff --git a/selfdrive/car/nissan/carcontroller.py b/selfdrive/car/nissan/carcontroller.py
index 83775462b7..c7bd231398 100644
--- a/selfdrive/car/nissan/carcontroller.py
+++ b/selfdrive/car/nissan/carcontroller.py
@@ -75,7 +75,7 @@ class CarController(CarControllerBase):
           self.packer, CS.lkas_hud_info_msg, steer_hud_alert
         ))
 
-    new_actuators = actuators.copy()
+    new_actuators = actuators.as_builder()
     new_actuators.steeringAngleDeg = apply_angle
 
     self.frame += 1
diff --git a/selfdrive/car/subaru/carcontroller.py b/selfdrive/car/subaru/carcontroller.py
index 22a1475b5b..d89ae8c639 100644
--- a/selfdrive/car/subaru/carcontroller.py
+++ b/selfdrive/car/subaru/carcontroller.py
@@ -136,7 +136,7 @@ class CarController(CarControllerBase):
         if self.frame % 2 == 0:
           can_sends.append(subarucan.create_es_static_2(self.packer))
 
-    new_actuators = actuators.copy()
+    new_actuators = actuators.as_builder()
     new_actuators.steer = self.apply_steer_last / self.p.STEER_MAX
     new_actuators.steerOutputCan = self.apply_steer_last
 
diff --git a/selfdrive/car/tesla/carcontroller.py b/selfdrive/car/tesla/carcontroller.py
index f217c4692d..e460111e32 100644
--- a/selfdrive/car/tesla/carcontroller.py
+++ b/selfdrive/car/tesla/carcontroller.py
@@ -60,7 +60,7 @@ class CarController(CarControllerBase):
 
     # TODO: HUD control
 
-    new_actuators = actuators.copy()
+    new_actuators = actuators.as_builder()
     new_actuators.steeringAngleDeg = self.apply_angle_last
 
     self.frame += 1
diff --git a/selfdrive/car/tests/test_car_interfaces.py b/selfdrive/car/tests/test_car_interfaces.py
index 72c1e27ab9..2138cf41f7 100755
--- a/selfdrive/car/tests/test_car_interfaces.py
+++ b/selfdrive/car/tests/test_car_interfaces.py
@@ -92,16 +92,16 @@ class TestCarInterfaces(unittest.TestCase):
     CC = car.CarControl.new_message(**cc_msg)
     for _ in range(10):
       car_interface.update(CC, [])
-      car_interface.apply(CC, now_nanos)
-      car_interface.apply(CC, now_nanos)
+      car_interface.apply(CC.as_reader(), now_nanos)
+      car_interface.apply(CC.as_reader(), now_nanos)
       now_nanos += DT_CTRL * 1e9  # 10 ms
 
     CC = car.CarControl.new_message(**cc_msg)
     CC.enabled = True
     for _ in range(10):
       car_interface.update(CC, [])
-      car_interface.apply(CC, now_nanos)
-      car_interface.apply(CC, now_nanos)
+      car_interface.apply(CC.as_reader(), now_nanos)
+      car_interface.apply(CC.as_reader(), now_nanos)
       now_nanos += DT_CTRL * 1e9  # 10ms
 
     # Test controller initialization
diff --git a/selfdrive/car/toyota/carcontroller.py b/selfdrive/car/toyota/carcontroller.py
index f2d8a4a7bc..bf601bc80c 100644
--- a/selfdrive/car/toyota/carcontroller.py
+++ b/selfdrive/car/toyota/carcontroller.py
@@ -173,7 +173,7 @@ class CarController(CarControllerBase):
     if self.frame % 20 == 0 and self.CP.flags & ToyotaFlags.DISABLE_RADAR.value:
       can_sends.append([0x750, 0, b"\x0F\x02\x3E\x00\x00\x00\x00\x00", 0])
 
-    new_actuators = actuators.copy()
+    new_actuators = actuators.as_builder()
     new_actuators.steer = apply_steer / self.params.STEER_MAX
     new_actuators.steerOutputCan = apply_steer
     new_actuators.steeringAngleDeg = self.last_angle
diff --git a/selfdrive/car/volkswagen/carcontroller.py b/selfdrive/car/volkswagen/carcontroller.py
index 5fc47c51c6..a4e0c8946a 100644
--- a/selfdrive/car/volkswagen/carcontroller.py
+++ b/selfdrive/car/volkswagen/carcontroller.py
@@ -112,7 +112,7 @@ class CarController(CarControllerBase):
       can_sends.append(self.CCS.create_acc_buttons_control(self.packer_pt, self.ext_bus, CS.gra_stock_values,
                                                            cancel=CC.cruiseControl.cancel, resume=CC.cruiseControl.resume))
 
-    new_actuators = actuators.copy()
+    new_actuators = actuators.as_builder()
     new_actuators.steer = self.apply_steer_last / self.CCP.STEER_MAX
     new_actuators.steerOutputCan = self.apply_steer_last