diff --git a/mjx/cuda_requirements.txt b/mjx/cuda_requirements.txt
index 2ced5d12..c8de6c4a 100644
--- a/mjx/cuda_requirements.txt
+++ b/mjx/cuda_requirements.txt
@@ -16,8 +16,8 @@ jax-cuda12-pjrt==0.5.3; python_version >= '3.10' \
 jax-cuda12-pjrt==0.4.30; python_version == '3.9' \
     --hash=sha256:895d0198ad99638fcaf976c47592e2a543eef79ea15fabd24a402d055390c328 \
     --hash=sha256:c36fb1e0c236563bf3a87e70f4d1ab28a31d7cf5d722c9ede30c4172116e8bcb
-warp-lang==1.12.0 \
-    --hash=sha256:c78c3701d5cad86c30ef5017410d294ec46a396bb0d502ee1c98743494f3a62f \
-    --hash=sha256:a1436f60a1881cd94f787e751a83fc0987626be2d3e2b4e74c64a6947c6d1266 \
-    --hash=sha256:a2d6decba693aba5b828573c4414fd6a3f4c4a934db9c322736ef2b3fa99fe76 \
-    --hash=sha256:697248edd2f1e2952f50e3db33b214af76173641a8894aacc467bed6dc247f8a
+warp-lang==1.12.1 \
+    --hash=sha256:98df3533a6c40a33cce961f8efa991006b30c9d286356e4cd77ea8ce86928f1d \
+    --hash=sha256:6bf01f10509488ba8eacaf4ec7fcf7cfbd503118b22e002ecba407b40a17424e \
+    --hash=sha256:af6d680e79c1be6e46ddf80ecaa358f222804f882f4683260a7b4abd80a0981b \
+    --hash=sha256:826b2f93df8e47eac0c751a8eb5a0533e2fc5434158c8896a63be53bfbd728c7
diff --git a/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/__init__.py b/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/__init__.py
index 3159bfe6..1a8431c3 100644
--- a/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/__init__.py
+++ b/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/__init__.py
@@ -1,14 +1,2 @@
 # SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-# http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
diff --git a/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/custom_call.py b/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/custom_call.py
index 0adf6435..dba3f715 100644
--- a/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/custom_call.py
+++ b/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/custom_call.py
@@ -1,17 +1,5 @@
 # SPDX-FileCopyrightText: Copyright (c) 2024 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-# http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
 
 import ctypes
 from functools import reduce
diff --git a/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/ffi.py b/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/ffi.py
index e9fe408f..c3f9e6e9 100644
--- a/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/ffi.py
+++ b/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/ffi.py
@@ -1,17 +1,5 @@
 # SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-# http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
 
 from __future__ import annotations
 
@@ -223,7 +211,7 @@ class FfiKernel:
 
         # register the callback
         FFI_CCALLFUNC = ctypes.CFUNCTYPE(ctypes.c_void_p, ctypes.POINTER(XLA_FFI_CallFrame))
-        self.callback_func = FFI_CCALLFUNC(lambda call_frame: self.ffi_callback(call_frame))
+        self.callback_func = FFI_CCALLFUNC(self.ffi_callback)
         ffi_ccall_address = ctypes.cast(self.callback_func, ctypes.c_void_p)
         ffi_capsule = jax.ffi.pycapsule(ffi_ccall_address.value)
         jax.ffi.register_ffi_target(self.name, ffi_capsule, platform="CUDA")
@@ -606,7 +594,7 @@ class FfiCallable:
 
         # register the callback
         FFI_CCALLFUNC = ctypes.CFUNCTYPE(ctypes.c_void_p, ctypes.POINTER(XLA_FFI_CallFrame))
-        self.callback_func = FFI_CCALLFUNC(lambda call_frame: self.ffi_callback(call_frame))
+        self.callback_func = FFI_CCALLFUNC(self.ffi_callback)
         ffi_ccall_address = ctypes.cast(self.callback_func, ctypes.c_void_p)
         ffi_capsule = jax.ffi.pycapsule(ffi_ccall_address.value)
         jax.ffi.register_ffi_target(self.name, ffi_capsule, platform="CUDA")
diff --git a/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/xla_ffi.py b/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/xla_ffi.py
index 2da12c4e..911ca2f1 100644
--- a/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/xla_ffi.py
+++ b/mjx/mujoco/mjx/third_party/warp/_src/jax_experimental/xla_ffi.py
@@ -1,17 +1,5 @@
 # SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-# http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
 
 import ctypes
 import enum
diff --git a/mjx/pyproject.toml b/mjx/pyproject.toml
index fb3c5a5d..e6a48dec 100644
--- a/mjx/pyproject.toml
+++ b/mjx/pyproject.toml
@@ -36,7 +36,7 @@ dependencies = [
 
 [project.optional-dependencies]
 warp = [
-    "warp-lang==1.12.0",
+    "warp-lang==1.12.1",
 ]
 
 [project.scripts]