diff --git a/src/jaxsim/high_level/joint.py b/src/jaxsim/high_level/joint.py
index 5676b7fc4..db8d54876 100644
--- a/src/jaxsim/high_level/joint.py
+++ b/src/jaxsim/high_level/joint.py
@@ -1,6 +1,6 @@
 import dataclasses
 import functools
-from typing import Any, Optional
+from typing import Any
 
 import jax.numpy as jnp
 import jax_dataclasses
@@ -54,7 +54,7 @@ def name(self) -> str:
         return self.joint_description.name
 
     @functools.partial(oop.jax_tf.method_ro)
-    def position(self, dof: Optional[int] = None) -> jtp.Float:
+    def position(self, dof: int | None = None) -> jtp.Float:
         """"""
 
         dof = dof if dof is not None else 0
@@ -65,7 +65,7 @@ def position(self, dof: Optional[int] = None) -> jtp.Float:
         )
 
     @functools.partial(oop.jax_tf.method_ro)
-    def velocity(self, dof: Optional[int] = None) -> jtp.Float:
+    def velocity(self, dof: int | None = None) -> jtp.Float:
         """"""
 
         dof = dof if dof is not None else 0
@@ -76,7 +76,7 @@ def velocity(self, dof: Optional[int] = None) -> jtp.Float:
         )
 
     @functools.partial(oop.jax_tf.method_ro)
-    def force_target(self, dof: Optional[int] = None) -> jtp.Float:
+    def force_target(self, dof: int | None = None) -> jtp.Float:
         """"""
 
         dof = dof if dof is not None else 0
@@ -89,7 +89,7 @@ def force_target(self, dof: Optional[int] = None) -> jtp.Float:
         )
 
     @functools.partial(oop.jax_tf.method_ro)
-    def position_limit(self, dof: Optional[int] = None) -> tuple[jtp.Float, jtp.Float]:
+    def position_limit(self, dof: int | None = None) -> tuple[jtp.Float, jtp.Float]:
         """"""
 
         dof = dof if dof is not None else 0
diff --git a/src/jaxsim/high_level/link.py b/src/jaxsim/high_level/link.py
index 97b0224cf..d82e1d258 100644
--- a/src/jaxsim/high_level/link.py
+++ b/src/jaxsim/high_level/link.py
@@ -1,6 +1,6 @@
 import dataclasses
 import functools
-from typing import Any, Optional
+from typing import Any
 
 import jax.lax
 import jax.numpy as jnp
@@ -122,7 +122,7 @@ def transform(self) -> jtp.Matrix:
         return self.parent_model.forward_kinematics()[self.index()]
 
     @functools.partial(oop.jax_tf.method_ro, static_argnames=["vel_repr"])
-    def velocity(self, vel_repr: Optional[VelRepr] = None) -> jtp.Vector:
+    def velocity(self, vel_repr: VelRepr | None = None) -> jtp.Vector:
         """"""
 
         v_WL = (
@@ -133,19 +133,19 @@ def velocity(self, vel_repr: Optional[VelRepr] = None) -> jtp.Vector:
         return v_WL
 
     @functools.partial(oop.jax_tf.method_ro, static_argnames=["vel_repr"])
-    def linear_velocity(self, vel_repr: Optional[VelRepr] = None) -> jtp.Vector:
+    def linear_velocity(self, vel_repr: VelRepr | None = None) -> jtp.Vector:
         """"""
 
         return self.velocity(vel_repr=vel_repr)[0:3]
 
     @functools.partial(oop.jax_tf.method_ro, static_argnames=["vel_repr"])
-    def angular_velocity(self, vel_repr: Optional[VelRepr] = None) -> jtp.Vector:
+    def angular_velocity(self, vel_repr: VelRepr | None = None) -> jtp.Vector:
         """"""
 
         return self.velocity(vel_repr=vel_repr)[3:6]
 
     @functools.partial(oop.jax_tf.method_ro, static_argnames=["output_vel_repr"])
-    def jacobian(self, output_vel_repr: Optional[VelRepr] = None) -> jtp.Matrix:
+    def jacobian(self, output_vel_repr: VelRepr | None = None) -> jtp.Matrix:
         """"""
 
         if output_vel_repr is None:
diff --git a/src/jaxsim/high_level/model.py b/src/jaxsim/high_level/model.py
index c733cfbde..520db2446 100644
--- a/src/jaxsim/high_level/model.py
+++ b/src/jaxsim/high_level/model.py
@@ -116,11 +116,11 @@ class Model(Vmappable):
     @staticmethod
     def build_from_model_description(
         model_description: Union[str, pathlib.Path, rod.Model],
-        model_name: Optional[str] = None,
+        model_name: str | None = None,
         vel_repr: VelRepr = VelRepr.Mixed,
         gravity: jtp.Array = jaxsim.physics.default_gravity(),
-        is_urdf: Optional[bool] = None,
-        considered_joints: Optional[List[str]] = None,
+        is_urdf: bool | None = None,
+        considered_joints: List[str] | None = None,
     ) -> "Model":
         """
         Build a Model object from a model description.
@@ -169,11 +169,11 @@ def build_from_model_description(
     @staticmethod
     def build_from_sdf(
         sdf: Union[str, pathlib.Path],
-        model_name: Optional[str] = None,
+        model_name: str | None = None,
         vel_repr: VelRepr = VelRepr.Mixed,
         gravity: jtp.Array = jaxsim.physics.default_gravity(),
-        is_urdf: Optional[bool] = None,
-        considered_joints: Optional[List[str]] = None,
+        is_urdf: bool | None = None,
+        considered_joints: List[str] | None = None,
     ) -> "Model":
         """
         Build a Model object from an SDF description.
@@ -197,7 +197,7 @@ def build_from_sdf(
     @staticmethod
     def build(
         physics_model: jaxsim.physics.model.physics_model.PhysicsModel,
-        model_name: Optional[str] = None,
+        model_name: str | None = None,
         vel_repr: VelRepr = VelRepr.Mixed,
     ) -> "Model":
         """
@@ -397,7 +397,7 @@ def joint_names(self) -> tuple[str, ...]:
 
     @functools.partial(oop.jax_tf.method_ro, jit=False, vmap=False)
     def links(
-        self, link_names: Optional[tuple[str, ...]] = None
+        self, link_names: tuple[str, ...] | None = None
     ) -> tuple[high_level.link.Link, ...]:
         """"""
 
@@ -421,7 +421,7 @@ def links(
 
     @functools.partial(oop.jax_tf.method_ro, jit=False, vmap=False)
     def joints(
-        self, joint_names: Optional[tuple[str, ...]] = None
+        self, joint_names: tuple[str, ...] | None = None
     ) -> tuple[high_level.joint.Joint, ...]:
         """"""
 
@@ -446,7 +446,7 @@ def joints(
     @functools.partial(oop.jax_tf.method_ro, static_argnames=["link_names", "terrain"])
     def in_contact(
         self,
-        link_names: Optional[tuple[str, ...]] = None,
+        link_names: tuple[str, ...] | None = None,
         terrain: Terrain = FlatTerrain(),
     ) -> jtp.Vector:
         """"""
@@ -484,9 +484,7 @@ def in_contact(
     # =================
 
     @functools.partial(oop.jax_tf.method_ro, static_argnames=["joint_names"])
-    def joint_positions(
-        self, joint_names: Optional[tuple[str, ...]] = None
-    ) -> jtp.Vector:
+    def joint_positions(self, joint_names: tuple[str, ...] | None = None) -> jtp.Vector:
         """"""
 
         return self.data.model_state.joint_positions[
@@ -496,8 +494,8 @@ def joint_positions(
     @functools.partial(oop.jax_tf.method_ro, static_argnames=["joint_names"])
     def joint_random_positions(
         self,
-        joint_names: Optional[tuple[str, ...]] = None,
-        key: Optional[jax.Array] = None,
+        joint_names: tuple[str, ...] | None = None,
+        key: jax.Array | None = None,
     ) -> jtp.Vector:
         """"""
 
@@ -517,7 +515,7 @@ def joint_random_positions(
 
     @functools.partial(oop.jax_tf.method_ro, static_argnames=["joint_names"])
     def joint_velocities(
-        self, joint_names: Optional[tuple[str, ...]] = None
+        self, joint_names: tuple[str, ...] | None = None
     ) -> jtp.Vector:
         """"""
 
@@ -527,7 +525,7 @@ def joint_velocities(
 
     @functools.partial(oop.jax_tf.method_ro, static_argnames=["joint_names"])
     def joint_generalized_forces_targets(
-        self, joint_names: Optional[tuple[str, ...]] = None
+        self, joint_names: tuple[str, ...] | None = None
     ) -> jtp.Vector:
         """"""
 
@@ -535,7 +533,7 @@ def joint_generalized_forces_targets(
 
     @functools.partial(oop.jax_tf.method_ro, static_argnames=["joint_names"])
     def joint_limits(
-        self, joint_names: Optional[tuple[str, ...]] = None
+        self, joint_names: tuple[str, ...] | None = None
     ) -> Tuple[jtp.Vector, jtp.Vector]:
         """"""
 
@@ -653,8 +651,8 @@ def external_forces(self) -> jtp.Matrix:
     def apply_external_force_to_link(
         self,
         link_name: str,
-        force: Optional[jtp.Array] = None,
-        torque: Optional[jtp.Array] = None,
+        force: jtp.Array | None = None,
+        torque: jtp.Array | None = None,
         additive: bool = True,
     ) -> None:
         """"""
@@ -708,8 +706,8 @@ def apply_external_force_to_link(
     def apply_external_force_to_link_com(
         self,
         link_name: str,
-        force: Optional[jtp.Array] = None,
-        torque: Optional[jtp.Array] = None,
+        force: jtp.Array | None = None,
+        torque: jtp.Array | None = None,
         additive: bool = True,
     ) -> None:
         """"""
@@ -779,7 +777,7 @@ def generalized_velocity(self) -> jtp.Vector:
 
     @functools.partial(oop.jax_tf.method_ro, static_argnames=["output_vel_repr"])
     def generalized_free_floating_jacobian(
-        self, output_vel_repr: Optional[VelRepr] = None
+        self, output_vel_repr: VelRepr | None = None
     ) -> jtp.Matrix:
         """"""
 
@@ -968,8 +966,8 @@ def forward_kinematics(self) -> jtp.Array:
     @functools.partial(oop.jax_tf.method_ro)
     def inverse_dynamics(
         self,
-        joint_accelerations: Optional[jtp.Vector] = None,
-        base_acceleration: Optional[jtp.Vector] = None,
+        joint_accelerations: jtp.Vector | None = None,
+        base_acceleration: jtp.Vector | None = None,
     ) -> Tuple[jtp.Vector, jtp.Vector]:
         """
         Compute inverse dynamics with the RNEA algorithm.
@@ -1058,7 +1056,7 @@ def to_inertial(C_vd_WB, W_H_C, C_v_WB, W_vl_WC):
 
     @functools.partial(oop.jax_tf.method_ro, static_argnames=["prefer_aba"])
     def forward_dynamics(
-        self, tau: Optional[jtp.Vector] = None, prefer_aba: float = True
+        self, tau: jtp.Vector | None = None, prefer_aba: float = True
     ) -> Tuple[jtp.Vector, jtp.Vector]:
         """"""
 
@@ -1070,7 +1068,7 @@ def forward_dynamics(
 
     @functools.partial(oop.jax_tf.method_ro)
     def forward_dynamics_aba(
-        self, tau: Optional[jtp.Vector] = None
+        self, tau: jtp.Vector | None = None
     ) -> Tuple[jtp.Vector, jtp.Vector]:
         """"""
 
@@ -1136,7 +1134,7 @@ def to_active(W_vd_WB, W_H_C, W_v_WB, W_vl_WC):
 
     @functools.partial(oop.jax_tf.method_ro)
     def forward_dynamics_crb(
-        self, tau: Optional[jtp.Vector] = None
+        self, tau: jtp.Vector | None = None
     ) -> Tuple[jtp.Vector, jtp.Vector]:
         """"""
 
@@ -1234,7 +1232,7 @@ def potential_energy(self) -> jtp.Float:
 
     @functools.partial(oop.jax_tf.method_rw, static_argnames=["joint_names"])
     def set_joint_generalized_force_targets(
-        self, forces: jtp.Vector, joint_names: Optional[tuple[str, ...]] = None
+        self, forces: jtp.Vector, joint_names: tuple[str, ...] | None = None
     ) -> None:
         """"""
 
@@ -1254,7 +1252,7 @@ def set_joint_generalized_force_targets(
 
     @functools.partial(oop.jax_tf.method_rw, static_argnames=["joint_names"])
     def reset_joint_positions(
-        self, positions: jtp.Vector, joint_names: Optional[tuple[str, ...]] = None
+        self, positions: jtp.Vector, joint_names: tuple[str, ...] | None = None
     ) -> None:
         """"""
 
@@ -1280,7 +1278,7 @@ def reset_joint_positions(
 
     @functools.partial(oop.jax_tf.method_rw, static_argnames=["joint_names"])
     def reset_joint_velocities(
-        self, velocities: jtp.Vector, joint_names: Optional[tuple[str, ...]] = None
+        self, velocities: jtp.Vector, joint_names: tuple[str, ...] | None = None
     ) -> None:
         """"""
 
@@ -1510,7 +1508,7 @@ def integrate(
 
     @functools.partial(oop.jax_tf.method_rw, static_argnames=["joint_names"])
     def set_motor_inertias(
-        self, inertias: jtp.Vector, joint_names: Optional[tuple[str, ...]] = None
+        self, inertias: jtp.Vector, joint_names: tuple[str, ...] | None = None
     ) -> None:
         joint_names = joint_names or self.joint_names()
 
@@ -1525,7 +1523,7 @@ def set_motor_inertias(
 
     @functools.partial(oop.jax_tf.method_rw, jit=False)
     def set_motor_gear_ratios(
-        self, gear_ratios: jtp.Vector, joint_names: Optional[tuple[str, ...]] = None
+        self, gear_ratios: jtp.Vector, joint_names: tuple[str, ...] | None = None
     ) -> None:
         joint_names = joint_names or self.joint_names()
 
@@ -1549,7 +1547,7 @@ def set_motor_gear_ratios(
     def set_motor_viscous_frictions(
         self,
         viscous_frictions: jtp.Vector,
-        joint_names: Optional[tuple[str, ...]] = None,
+        joint_names: tuple[str, ...] | None = None,
     ) -> None:
         joint_names = joint_names or self.joint_names()
 
@@ -1680,9 +1678,7 @@ def active_to_inertial_representation(
         else:
             raise ValueError(self.velocity_representation)
 
-    def _joint_indices(
-        self, joint_names: Optional[tuple[str, ...]] = None
-    ) -> jtp.Vector:
+    def _joint_indices(self, joint_names: tuple[str, ...] | None = None) -> jtp.Vector:
         """"""
 
         if joint_names is None:
diff --git a/src/jaxsim/parsers/descriptions/joint.py b/src/jaxsim/parsers/descriptions/joint.py
index 4a6d54fc5..0ac1ece3e 100644
--- a/src/jaxsim/parsers/descriptions/joint.py
+++ b/src/jaxsim/parsers/descriptions/joint.py
@@ -1,6 +1,6 @@
 import dataclasses
 import enum
-from typing import Optional, Tuple, Union
+from typing import Tuple, Union
 
 import jax_dataclasses
 import numpy as np
@@ -63,7 +63,7 @@ class JointDescription(JaxsimDataclass):
     child: LinkDescription = dataclasses.dataclass(repr=False)
     parent: LinkDescription = dataclasses.dataclass(repr=False)
 
-    index: Optional[int] = None
+    index: int | None = None
 
     friction_static: float = 0.0
     friction_viscous: float = 0.0
diff --git a/src/jaxsim/parsers/descriptions/link.py b/src/jaxsim/parsers/descriptions/link.py
index b2f1d2c17..b2a7fe55f 100644
--- a/src/jaxsim/parsers/descriptions/link.py
+++ b/src/jaxsim/parsers/descriptions/link.py
@@ -1,5 +1,5 @@
 import dataclasses
-from typing import List, Optional
+from typing import List
 
 import jax.numpy as jnp
 import jax_dataclasses
@@ -19,7 +19,7 @@ class LinkDescription(JaxsimDataclass):
     name: Static[str]
     mass: float
     inertia: jtp.Matrix
-    index: Optional[int] = None
+    index: int | None = None
     parent: Static["LinkDescription"] = dataclasses.field(default=None, repr=False)
     pose: jtp.Matrix = dataclasses.field(default_factory=lambda: jnp.eye(4), repr=False)
     children: Static[List["LinkDescription"]] = dataclasses.field(
diff --git a/src/jaxsim/parsers/descriptions/model.py b/src/jaxsim/parsers/descriptions/model.py
index f29807c38..8a1a7b757 100644
--- a/src/jaxsim/parsers/descriptions/model.py
+++ b/src/jaxsim/parsers/descriptions/model.py
@@ -1,6 +1,6 @@
 import dataclasses
 import itertools
-from typing import List, Optional
+from typing import List
 
 from jaxsim import logging
 
@@ -23,8 +23,8 @@ def build_model_from(
         joints: List[JointDescription],
         collisions: List[CollisionShape] = (),
         fixed_base: bool = False,
-        base_link_name: Optional[str] = None,
-        considered_joints: Optional[List[str]] = None,
+        base_link_name: str | None = None,
+        considered_joints: List[str] | None = None,
         model_pose: RootPose = RootPose(),
     ) -> "ModelDescription":
         # Create the full kinematic graph
diff --git a/src/jaxsim/parsers/kinematic_graph.py b/src/jaxsim/parsers/kinematic_graph.py
index e33193628..1c7432daa 100644
--- a/src/jaxsim/parsers/kinematic_graph.py
+++ b/src/jaxsim/parsers/kinematic_graph.py
@@ -98,7 +98,7 @@ def __post_init__(self):
     def build_from(
         links: List[descriptions.LinkDescription],
         joints: List[descriptions.JointDescription],
-        root_link_name: Optional[str] = None,
+        root_link_name: str | None = None,
         root_pose: RootPose = RootPose(),
     ) -> "KinematicGraph":
         if root_link_name is None:
diff --git a/src/jaxsim/parsers/rod/parser.py b/src/jaxsim/parsers/rod/parser.py
index f06a47bb1..99894d0b5 100644
--- a/src/jaxsim/parsers/rod/parser.py
+++ b/src/jaxsim/parsers/rod/parser.py
@@ -27,14 +27,14 @@ class SDFData(NamedTuple):
     joint_descriptions: List[descriptions.JointDescription]
     collision_shapes: List[descriptions.CollisionShape]
 
-    sdf_model: Optional[rod.Model] = None
+    sdf_model: rod.Model | None = None
     model_pose: kinematic_graph.RootPose = kinematic_graph.RootPose()
 
 
 def extract_model_data(
     model_description: Union[pathlib.Path, str, rod.Model],
-    model_name: Optional[str] = None,
-    is_urdf: Optional[bool] = None,
+    model_name: str | None = None,
+    is_urdf: bool | None = None,
 ) -> SDFData:
     """
     Extract data from an SDF/URDF resource useful to build a JaxSim model.
diff --git a/src/jaxsim/physics/algos/aba.py b/src/jaxsim/physics/algos/aba.py
index 1b5d5abbf..98cb12500 100644
--- a/src/jaxsim/physics/algos/aba.py
+++ b/src/jaxsim/physics/algos/aba.py
@@ -1,4 +1,4 @@
-from typing import Optional, Tuple
+from typing import Tuple
 
 import jax
 import jax.numpy as jnp
@@ -18,7 +18,7 @@ def aba(
     q: jtp.Vector,
     qd: jtp.Vector,
     tau: jtp.Vector,
-    f_ext: Optional[jtp.Matrix] = None,
+    f_ext: jtp.Matrix | None = None,
 ) -> Tuple[jtp.Vector, jtp.Vector]:
     """
     Articulated Body Algorithm (ABA) algorithm for forward dynamics.
diff --git a/src/jaxsim/physics/algos/aba_motors.py b/src/jaxsim/physics/algos/aba_motors.py
index 7c3060790..fd7873ffe 100644
--- a/src/jaxsim/physics/algos/aba_motors.py
+++ b/src/jaxsim/physics/algos/aba_motors.py
@@ -1,4 +1,4 @@
-from typing import Optional, Tuple
+from typing import Tuple
 
 import jax
 import jax.numpy as jnp
@@ -18,7 +18,7 @@ def aba(
     q: jtp.Vector,
     qd: jtp.Vector,
     tau: jtp.Vector,
-    f_ext: Optional[jtp.Matrix] = None,
+    f_ext: jtp.Matrix | None = None,
 ) -> Tuple[jtp.Vector, jtp.Vector]:
     """
     Articulated Body Algorithm (ABA) algorithm with motor dynamics for forward dynamics.
diff --git a/src/jaxsim/physics/algos/rnea.py b/src/jaxsim/physics/algos/rnea.py
index c51de1182..8a1c62116 100644
--- a/src/jaxsim/physics/algos/rnea.py
+++ b/src/jaxsim/physics/algos/rnea.py
@@ -1,4 +1,4 @@
-from typing import Optional, Tuple
+from typing import Tuple
 
 import jax
 import jax.numpy as jnp
@@ -19,7 +19,7 @@ def rnea(
     qd: jtp.Vector,
     qdd: jtp.Vector,
     a0fb: jtp.Vector = jnp.zeros(6),
-    f_ext: Optional[jtp.Matrix] = None,
+    f_ext: jtp.Matrix | None = None,
 ) -> Tuple[jtp.Vector, jtp.Vector]:
     """
     Recursive Newton-Euler Algorithm (RNEA) algorithm for inverse dynamics.
diff --git a/src/jaxsim/physics/algos/rnea_motors.py b/src/jaxsim/physics/algos/rnea_motors.py
index e324e8d86..84a8c02cd 100644
--- a/src/jaxsim/physics/algos/rnea_motors.py
+++ b/src/jaxsim/physics/algos/rnea_motors.py
@@ -1,4 +1,4 @@
-from typing import Optional, Tuple
+from typing import Tuple
 
 import jax
 import jax.numpy as jnp
@@ -19,7 +19,7 @@ def rnea(
     qd: jtp.Vector,
     qdd: jtp.Vector,
     a0fb: jtp.Vector = jnp.zeros(6),
-    f_ext: Optional[jtp.Matrix] = None,
+    f_ext: jtp.Matrix | None = None,
 ) -> Tuple[jtp.Vector, jtp.Vector]:
     """
     Recursive Newton-Euler Algorithm (RNEA) algorithm for inverse dynamics.
diff --git a/src/jaxsim/physics/algos/soft_contacts.py b/src/jaxsim/physics/algos/soft_contacts.py
index b3a8b85f9..b7627bf9c 100644
--- a/src/jaxsim/physics/algos/soft_contacts.py
+++ b/src/jaxsim/physics/algos/soft_contacts.py
@@ -1,5 +1,5 @@
 import dataclasses
-from typing import Optional, Tuple
+from typing import Tuple
 
 import jax
 import jax.flatten_util
@@ -52,7 +52,7 @@ def collidable_points_pos_vel(
     model: PhysicsModel,
     q: jtp.Vector,
     qd: jtp.Vector,
-    xfb: Optional[jtp.Vector] = None,
+    xfb: jtp.Vector | None = None,
 ) -> Tuple[jtp.Matrix, jtp.Matrix]:
     """
     Compute the position and linear velocity of collidable points in the world frame.
diff --git a/src/jaxsim/physics/algos/utils.py b/src/jaxsim/physics/algos/utils.py
index 690fd3217..0204986e1 100644
--- a/src/jaxsim/physics/algos/utils.py
+++ b/src/jaxsim/physics/algos/utils.py
@@ -1,4 +1,4 @@
-from typing import Optional, Tuple
+from typing import Tuple
 
 import jax.numpy as jnp
 
@@ -8,12 +8,12 @@
 
 def process_inputs(
     physics_model: PhysicsModel,
-    xfb: Optional[jtp.Vector] = None,
-    q: Optional[jtp.Vector] = None,
-    qd: Optional[jtp.Vector] = None,
-    qdd: Optional[jtp.Vector] = None,
-    tau: Optional[jtp.Vector] = None,
-    f_ext: Optional[jtp.Matrix] = None,
+    xfb: jtp.Vector | None = None,
+    q: jtp.Vector | None = None,
+    qd: jtp.Vector | None = None,
+    qdd: jtp.Vector | None = None,
+    tau: jtp.Vector | None = None,
+    f_ext: jtp.Matrix | None = None,
 ) -> Tuple[jtp.Vector, jtp.Vector, jtp.Vector, jtp.Vector, jtp.Vector, jtp.Matrix]:
     """
     Adjust the inputs to the physics model.
diff --git a/src/jaxsim/simulation/ode.py b/src/jaxsim/simulation/ode.py
index c5e145f4d..f22941da4 100644
--- a/src/jaxsim/simulation/ode.py
+++ b/src/jaxsim/simulation/ode.py
@@ -74,10 +74,10 @@ def compute_contact_forces(
 
 def dx_dt(
     x: ode_data.ODEState,
-    t: Optional[jtp.Float],
     physics_model: PhysicsModel,
     soft_contacts_params: SoftContactsParams = SoftContactsParams(),
-    ode_input: Optional[ode_data.ODEInput] = None,
+    t: jtp.Float | None = None,
+    ode_input: ode_data.ODEInput | None = None,
     terrain: Terrain = FlatTerrain(),
 ) -> Tuple[ode_data.ODEState, Dict[str, Any]]:
     """
@@ -231,7 +231,7 @@ def dx_dt(
     # Build the full derivative of ODEState
     # =====================================
 
-    def fix_one_dof(vector: jtp.Vector) -> Optional[jtp.Vector]:
+    def fix_one_dof(vector: jtp.Vector) -> jtp.Vector | None:
         """Fix the shape of computed quantities for models with just 1 DoF."""
 
         if vector is None:
diff --git a/src/jaxsim/simulation/ode_integration.py b/src/jaxsim/simulation/ode_integration.py
index fe98e4a0f..c34d2bd36 100644
--- a/src/jaxsim/simulation/ode_integration.py
+++ b/src/jaxsim/simulation/ode_integration.py
@@ -1,6 +1,6 @@
 import enum
 import functools
-from typing import Any, Dict, Optional, Tuple, Union
+from typing import Any, Dict, Tuple, Union
 
 import jax.flatten_util
 from jax.experimental.ode import odeint
@@ -39,7 +39,7 @@ def ode_integration_euler(
     physics_model: PhysicsModel,
     soft_contacts_params: SoftContactsParams = SoftContactsParams(),
     terrain: Terrain = FlatTerrain(),
-    ode_input: Optional[ode.ode_data.ODEInput] = None,
+    ode_input: ode.ode_data.ODEInput | None = None,
     *args,
     num_sub_steps: int = 1,
     return_aux: bool = False,
@@ -70,7 +70,7 @@ def ode_integration_euler_semi_implicit(
     physics_model: PhysicsModel,
     soft_contacts_params: SoftContactsParams = SoftContactsParams(),
     terrain: Terrain = FlatTerrain(),
-    ode_input: Optional[ode.ode_data.ODEInput] = None,
+    ode_input: ode.ode_data.ODEInput | None = None,
     *args,
     num_sub_steps: int = 1,
     return_aux: bool = False,
@@ -101,7 +101,7 @@ def ode_integration_rk4(
     physics_model: PhysicsModel,
     soft_contacts_params: SoftContactsParams = SoftContactsParams(),
     terrain: Terrain = FlatTerrain(),
-    ode_input: Optional[ode.ode_data.ODEInput] = None,
+    ode_input: ode.ode_data.ODEInput | None = None,
     *args,
     num_sub_steps=1,
     return_aux: bool = False,
diff --git a/src/jaxsim/simulation/simulator.py b/src/jaxsim/simulation/simulator.py
index 4f4f5b9a4..75dbd9d93 100644
--- a/src/jaxsim/simulation/simulator.py
+++ b/src/jaxsim/simulation/simulator.py
@@ -90,7 +90,7 @@ def build(
         steps_per_run: jtp.Int = 1,
         velocity_representation: VelRepr = VelRepr.Inertial,
         integrator_type: IntegratorType = IntegratorType.EulerSemiImplicit,
-        simulator_data: Optional[SimulatorData] = None,
+        simulator_data: SimulatorData | None = None,
     ) -> "JaxSim":
         """
         Build a JaxSim simulator object.
@@ -219,9 +219,7 @@ def get_model(self, model_name: str) -> Model:
         return self.data.models[model_name]
 
     @functools.partial(oop.jax_tf.method_ro, jit=False, vmap=False)
-    def models(
-        self, model_names: Optional[tuple[str, ...]] = None
-    ) -> tuple[Model, ...]:
+    def models(self, model_names: tuple[str, ...] | None = None) -> tuple[Model, ...]:
         """
         Return the simulated models.
 
@@ -259,8 +257,8 @@ def set_gravity(self, gravity: jtp.Vector) -> None:
     def insert_model_from_description(
         self,
         model_description: Union[pathlib.Path, str, rod.Model],
-        model_name: Optional[str] = None,
-        considered_joints: Optional[List[str]] = None,
+        model_name: str | None = None,
+        considered_joints: List[str] | None = None,
     ) -> Model:
         """
         Insert a model from a model description.
@@ -302,8 +300,8 @@ def insert_model_from_description(
     def insert_model_from_sdf(
         self,
         sdf: Union[pathlib.Path, str],
-        model_name: Optional[str] = None,
-        considered_joints: Optional[List[str]] = None,
+        model_name: str | None = None,
+        considered_joints: List[str] | None = None,
     ) -> Model:
         """
         Insert a model from an SDF resource.
@@ -324,7 +322,7 @@ def insert_model_from_sdf(
     def insert_model(
         self,
         model_description: descriptions.ModelDescription,
-        model_name: Optional[str] = None,
+        model_name: str | None = None,
     ) -> Model:
         """
         Insert a model from a model description object.
@@ -436,9 +434,8 @@ def step(self, clear_inputs: bool = False) -> Dict[str, StepData]:
     def step_over_horizon(
         self,
         horizon_steps: jtp.Int,
-        callback_handler: Optional[
-            Union["scb.SimulatorCallback", "scb.CallbackHandler"]
-        ] = None,
+        callback_handler: Union["scb.SimulatorCallback", "scb.CallbackHandler"]
+        | None = None,
         clear_inputs: jtp.Bool = False,
     ) -> Union[
         "JaxSim",
diff --git a/tests/utils_idyntree.py b/tests/utils_idyntree.py
index 201ca13a4..a58391067 100644
--- a/tests/utils_idyntree.py
+++ b/tests/utils_idyntree.py
@@ -1,6 +1,6 @@
 import dataclasses
 import pathlib
-from typing import List, Optional, Union
+from typing import List, Union
 
 import idyntree.bindings as idt
 import numpy as np
@@ -66,11 +66,11 @@ def build(
 
     def set_robot_state(
         self,
-        joint_positions: Optional[npt.NDArray] = None,
-        joint_velocities: Optional[npt.NDArray] = None,
+        joint_positions: npt.NDArray | None = None,
+        joint_velocities: npt.NDArray | None = None,
         base_transform: npt.NDArray = np.eye(4),
         base_velocity: npt.NDArray = np.zeros(6),
-        world_gravity: Optional[npt.NDArray] = None,
+        world_gravity: npt.NDArray | None = None,
     ) -> None:
         joint_positions = (
             joint_positions if joint_positions is not None else np.zeros(self.dofs())