diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..309dfdb
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "jetson-nano-wheels/commons"]
+	path = jetson-nano-wheels/commons
+	url = git@github.com:jetson-nano-wheels/commons
diff --git a/README.md b/README.md
index e568502..ee3a119 100644
--- a/README.md
+++ b/README.md
@@ -11,18 +11,19 @@ If you have `pip` (which should be run in a suitable virtual environment) this s
 pip install 'https://github.com/jetson-nano-wheels/python3.6-blis-0.7.4/releases/download/v0.0.1/blis-0.7.4-cp36-cp36m-linux_aarch64.whl'
 ```
 
-
 ## How to contribute
 
   1. [Fork this repo](https://github.com/jetson-nano-wheels/python3.6-blis-0.7.4/fork)
-  2. Add a branch for your new feature.
-  3. Run the `init.sh` script.
+  2. Update submodules.
+  3. Add a branch for your new feature.
+  4. Run the `init.sh` script.
 
 Like this:
 
 ```sh
 git clone git@github.com:jetson-nano-wheels/python3.6-blis-0.7.4
 cd python3.6-blis-0.7.4
+git submodule update --recursive --init
 git checkout -b feature-my-fancy-addition
 ./init.sh
 ```
diff --git a/build.sh b/build.sh
index ec66028..097bb10 100755
--- a/build.sh
+++ b/build.sh
@@ -3,7 +3,7 @@
 ./init.sh
 source venv/bin/activate
 
-source ../commons/envs.sh
+source jetson-nano-wheels/commons/envs.sh
 
 PIP_CONSTRAINT=constraint.txt \
 	      pip wheel -vv --only-binary 'numpy' --no-binary 'blis' 'blis>=0.4.0,<0.8.0' -w dist
diff --git a/jetson-nano-wheels/commons b/jetson-nano-wheels/commons
new file mode 160000
index 0000000..1b85bf3
--- /dev/null
+++ b/jetson-nano-wheels/commons
@@ -0,0 +1 @@
+Subproject commit 1b85bf3dda0d8b9acf8814901be18f758c29dbb1