diff --git a/carveme/cli/carve.py b/carveme/cli/carve.py
index c99f186..99b7fa5 100755
--- a/carveme/cli/carve.py
+++ b/carveme/cli/carve.py
@@ -211,8 +211,9 @@ def maincall(inputfile, input_type='protein', outputfile=None, diamond_args=None
 
         ensemble = build_ensemble(universe_model, scores, ensemble_size, init_env=init_env)
 
-        annotate_genes(ensemble, gene2gene, gene_annotations)
+        annotate_genes(ensemble.model, gene2gene, gene_annotations)
         save_ensemble(ensemble, outputfile, flavor=flavor)
+        return
 
     if model is None:
         print("Failed to build model.")
diff --git a/carveme/reconstruction/carving.py b/carveme/reconstruction/carving.py
index 02e6b7d..c9f4398 100755
--- a/carveme/reconstruction/carving.py
+++ b/carveme/reconstruction/carving.py
@@ -313,3 +313,5 @@ def build_ensemble(model, reaction_scores, size, init_env=None):
 
     if init_env:
         init_env.apply(ensemble.model, inplace=True, warning=False)
+
+    return ensemble
\ No newline at end of file