diff --git a/appveyor.yml b/appveyor.yml
index b41f4af5a..146b5837e 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -20,7 +20,7 @@ build_script:
   - CMD: SET
   - conda config --set always_yes yes
   - conda update conda
-  - conda install -c conda-forge python=3.8 numpy gdal pytest meshpy cython scipy netcdf4 matplotlib dill future gitpython utm backports.zoneinfo pymetis mpi4py msmpi Pmw
+  - conda install -c conda-forge python=3.8 brotlipy numpy gdal pytest meshpy cython scipy netcdf4 matplotlib dill future gitpython utm backports.zoneinfo pymetis mpi4py msmpi Pmw
   # setup for mingw compiler 
   - conda install -c conda-forge libpython m2w64-toolchain
   # there was a bug with distutil not picking mingw comiler for anuga