diff --git a/selfdrive/car/data_structures.py b/selfdrive/car/data_structures.py
index 1b1dc129bd..ea4fa44dc7 100644
--- a/selfdrive/car/data_structures.py
+++ b/selfdrive/car/data_structures.py
@@ -1,5 +1,14 @@
-from dataclasses import dataclass
-from enum import StrEnum as _StrEnum, auto
+from dataclasses import dataclass, fields, is_dataclass
+from enum import Enum, StrEnum as _StrEnum, auto
+# from typing import Type, TypeVar
+from typing import Type, TypeVar, TYPE_CHECKING, Any, get_type_hints, get_origin
+
+if TYPE_CHECKING:
+    from _typeshed import DataclassInstance
+#
+# DataclassT = TypeVar("DataclassT", bound="DataclassInstance")
+#
+# T = TypeVar('T', bound='Struct')
 
 
 class StrEnum(_StrEnum):
@@ -9,18 +18,99 @@ class StrEnum(_StrEnum):
     return name
 
 
+# class Struct:
+#   @classmethod
+#   def new_message(cls, **kwargs):
+#     init_values = {}
+#     for f in fields(cls):
+#       init_values[f.name] = kwargs.get(f.name, f.type())
+#
+#     return cls(**init_values)
+
+T = TypeVar('T', bound='DataclassInstance')
+
+
+class Struct:
+  @classmethod
+  def new_message(cls: Type[T], **kwargs: Any) -> T:
+    if not is_dataclass(cls):
+      raise TypeError(f"{cls.__name__} is not a dataclass")
+
+    init_values = {}
+    type_hints = get_type_hints(cls)
+    print(type_hints)
+    for f in fields(cls):
+      field_type = type_hints[f.name]
+      print(f.name, f.type, field_type)
+      print(issubclass(field_type, Enum))
+      if issubclass(field_type, Enum):
+        init_values[f.name] = kwargs.get(f.name, list(field_type)[0])
+        # TODO: fix this
+        # assert issubclass(init_values[f.name], type(field_type)), f"Expected {field_type} for {f.name}, got {type(init_values[f.name])}"
+      else:
+        # FIXME: typing check hack since mypy doesn't catch anything
+        init_values[f.name] = kwargs.get(f.name, field_type())
+        print('field_type', field_type, f.type)
+        # TODO: this is so bad
+        assert isinstance(init_values[f.name], get_origin(f.type) or f.type), f"Expected {field_type} for {f.name}, got {type(init_values[f.name])}"
+
+    return cls(**init_values)
+
+
 @dataclass
-class CarParams:
+class RadarData(Struct):
+  errors: list['Error']
+  points: list['RadarPoint']
+
+  class Error(StrEnum):
+    canError = auto()
+    fault = auto()
+    wrongConfig = auto()
+
+  @dataclass
+  class RadarPoint(Struct):
+    trackId: int  # no trackId reuse
+
+    # these 3 are the minimum required
+    dRel: float  # m from the front bumper of the car
+    yRel: float  # m
+    vRel: float  # m/s
+
+    # these are optional and valid if they are not NaN
+    aRel: float  # m/s^2
+    yvRel: float  # m/s
+
+    # some radars flag measurements VS estimates
+    measured: bool
+
+
+@dataclass
+class CarParams(Struct):
   carName: str
   carFingerprint: str
   fuzzyFingerprint: bool
 
   notCar: bool  # flag for non-car robotics platforms
 
+  carFw: list['CarFw']
+
   class SteerControlType(StrEnum):
     torque = auto()
     angle = auto()
 
+  @dataclass
+  class CarFw(Struct):
+    ecu: 'CarParams.Ecu'
+    fwVersion: bytes
+    address: int
+    subAddress: int
+    responseAddress: int
+    request: list[bytes]
+    brand: str
+    bus: int
+    logging: bool
+    obdMultiplexing: bool
+
   class Ecu(StrEnum):
     eps = auto()
     abs = auto()
@@ -52,3 +142,12 @@ class CarParams:
     programmedFuelInjection = auto()
 
     debug = auto()
+
+
+# CP: CarParams = CarParams.new_message(carName='toyota', fuzzyFingerprint=123)
+# CP: CarParams = CarParams(carName='toyota', fuzzyFingerprint=123)
+
+import ast
+
+
+# test = ast.literal_eval('CarParams.CarFw')
diff --git a/selfdrive/car/toyota/carcontroller.py b/selfdrive/car/toyota/carcontroller.py
index 8f7a7ed9dd..e166682a1a 100644
--- a/selfdrive/car/toyota/carcontroller.py
+++ b/selfdrive/car/toyota/carcontroller.py
@@ -1,6 +1,7 @@
 from cereal import car
 from openpilot.selfdrive.car import apply_meas_steer_torque_limits, apply_std_steer_angle_limits, common_fault_avoidance, make_tester_present_msg
 from openpilot.selfdrive.car.can_definitions import CanData
+from openpilot.selfdrive.car.data_structures import CarParams
 from openpilot.selfdrive.car.helpers import clip
 from openpilot.selfdrive.car.interfaces import CarControllerBase
 from openpilot.selfdrive.car.toyota import toyotacan
@@ -9,7 +10,7 @@ from openpilot.selfdrive.car.toyota.values import CAR, STATIC_DSU_MSGS, NO_STOP_
                                         UNSUPPORTED_DSU_CAR
 from opendbc.can.packer import CANPacker
 
-SteerControlType = car.CarParams.SteerControlType
+SteerControlType = CarParams.SteerControlType
 VisualAlert = car.CarControl.HUDControl.VisualAlert
 
 # LKA limits