diff --git a/envs/testing.yml b/envs/testing.yml
index dca8be4..5fb446a 100644
--- a/envs/testing.yml
+++ b/envs/testing.yml
@@ -12,6 +12,7 @@ dependencies:
   - networkx
   - numba>=0.53
   - numexpr
+  - sparse
   - filelock
   - flake8
   # required for testing