diff --git a/chai_lab/chai1.py b/chai_lab/chai1.py
index 9170a17..ffd05af 100644
--- a/chai_lab/chai1.py
+++ b/chai_lab/chai1.py
@@ -1047,7 +1047,7 @@ def avg_per_token_1d(x):
 
         scores_out_path = output_dir.joinpath(f"scores.model_idx_{idx}.npz")
 
-        np.savez(scores_out_path, **get_scores(ranking_outputs))
+        np.savez(scores_out_path, allow_pickle=False, **get_scores(ranking_outputs))
 
     return StructureCandidates(
         cif_paths=cif_paths,
diff --git a/requirements.in b/requirements.in
index a51256d..105d673 100644
--- a/requirements.in
+++ b/requirements.in
@@ -20,7 +20,7 @@ modelcif>=1.0      # mmcif writing, confirmed to work currently latest 1.0
 
 
 # computing, dl
-numpy~=1.21
+numpy>=1.21
 pandas[parquet,gcp,aws]~=2.1 
 pandera>=0.24       # pandera.pandas requires >= 0.24
 numba>=0.59