diff --git a/appveyor.yml b/appveyor.yml
index 6358cc3a..19187e73 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -54,7 +54,8 @@ install:
   # compiled extensions and are not provided as pre-built wheel packages,
   # pip will build them from source using the MSVC compiler matching the
   # target Python version and architecture
-  - "%CMD_IN_ENV% pip install cython numpy"
+  - "%CMD_IN_ENV% pip install cython"
+  - "%CMD_IN_ENV% pip install -i https://pypi.binstar.org/carlkl/simple numpy"
 
 build: false  # Not a C# project, build stuff at the test step instead.