diff --git a/.github/CONTRIBUTING.md b/.github/CONTRIBUTING.md
index e9fb69c2..d0870893 100644
--- a/.github/CONTRIBUTING.md
+++ b/.github/CONTRIBUTING.md
@@ -46,7 +46,7 @@ outlined on that page and do not file a public issue.
 ## Coding Style
 We follow these [python](http://google.github.io/styleguide/pyguide.html) and [C++](https://google.github.io/styleguide/cppguide.html) style guides.
 
-For the linter to work, you will need to install `black`, `flake`, `isort` and `clang-format`, and
+For the linter to work, you will need to install `black`, `flake`, `usort` and `clang-format`, and
 they need to be fairly up to date.
 
 ## License
diff --git a/INSTALL.md b/INSTALL.md
index 1202df08..2cf16c4a 100644
--- a/INSTALL.md
+++ b/INSTALL.md
@@ -43,7 +43,7 @@ export CUB_HOME=$PWD/cub-1.10.0
 For developing on top of PyTorch3D or contributing, you will need to run the linter and tests. If you want to run any of the notebook tutorials as `docs/tutorials` or the examples in `docs/examples` you will also need matplotlib and OpenCV.
 - scikit-image
 - black
-- isort
+- usort
 - flake8
 - matplotlib
 - tdqm
@@ -59,7 +59,7 @@ conda install jupyter
 pip install scikit-image matplotlib imageio plotly opencv-python
 
 # Tests/Linting
-pip install black 'isort<5' flake8 flake8-bugbear flake8-comprehensions
+pip install black usort flake8 flake8-bugbear flake8-comprehensions
 ```
 
 ## Installing prebuilt binaries for PyTorch3D
diff --git a/dev/linter.sh b/dev/linter.sh
index 8fa58b21..b1d32c25 100755
--- a/dev/linter.sh
+++ b/dev/linter.sh
@@ -22,8 +22,14 @@
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
 DIR=$(dirname "${DIR}")
 
-echo "Running isort..."
-isort -y -sp "${DIR}"
+if [[ -f "${DIR}/tests/TARGETS" ]]
+then
+  pyfmt "${DIR}"
+else
+# run usort externally only
+  echo "Running usort..."
+  usort  "${DIR}"
+fi
 
 echo "Running black..."
 black "${DIR}"
diff --git a/pytorch3d/implicitron/third_party/hyperlayers.py b/pytorch3d/implicitron/third_party/hyperlayers.py
index 640a14ed..1fb32171 100644
--- a/pytorch3d/implicitron/third_party/hyperlayers.py
+++ b/pytorch3d/implicitron/third_party/hyperlayers.py
@@ -2,9 +2,9 @@
 # fmt: off
 # flake8: noqa
 '''Pytorch implementations of hyper-network modules.
-isort:skip_file
 '''
 import functools
+
 import torch
 import torch.nn as nn
 
diff --git a/pytorch3d/implicitron/third_party/pytorch_prototyping.py b/pytorch3d/implicitron/third_party/pytorch_prototyping.py
index 0823b953..7dd973fc 100644
--- a/pytorch3d/implicitron/third_party/pytorch_prototyping.py
+++ b/pytorch3d/implicitron/third_party/pytorch_prototyping.py
@@ -2,7 +2,6 @@
 # fmt: off
 # flake8: noqa
 '''A number of custom pytorch modules with sane defaults that I find useful for model prototyping.
-isort:skip_file
 '''
 import torch
 import torch.nn as nn
diff --git a/setup.py b/setup.py
index ce007f52..98b83410 100755
--- a/setup.py
+++ b/setup.py
@@ -144,7 +144,7 @@ setup(
     install_requires=["fvcore", "iopath"],
     extras_require={
         "all": ["matplotlib", "tqdm>4.29.0", "imageio", "ipywidgets"],
-        "dev": ["flake8", "isort", "black==19.3b0"],
+        "dev": ["flake8", "usort", "black==19.3b0"],
         "implicitron": ["hydra-core>=1.1", "visdom", "lpips", "matplotlib"],
     },
     entry_points={