diff --git a/workflow/envs/env.yaml b/workflow/envs/env.yaml
index c5caef3..e1b76ab 100644
--- a/workflow/envs/env.yaml
+++ b/workflow/envs/env.yaml
@@ -6,7 +6,7 @@ channels:
 dependencies:
   - numpy
   - numba
-  - cooler>=0.9
+  - cooler==0.8.11
   - pandas==1.5
   - minimap2==2.18
   - bedtools