diff --git a/env-dev.yml b/env-dev.yml
index f610ff7..08b2ecb 100644
--- a/env-dev.yml
+++ b/env-dev.yml
@@ -7,6 +7,7 @@ dependencies:
   # Use latest changes from payu's master branch
   - pip:
     - git+https://github.com/payu-org/payu.git@master
+    - mule @ git+https://github.com/metomi/mule@cce4b99c7046217b1ec1192118a786636e0d8e54#subdirectory=mule
   - f90nml
   - conda-lock
   - conda-pack
@@ -14,4 +15,5 @@ dependencies:
   - git
   - nco
   - pytest
-  - openssh>=8.3
\ No newline at end of file
+  - openssh>=8.3
+  - xarray
\ No newline at end of file