diff --git a/lib/galaxy/model/custom_types.py b/lib/galaxy/model/custom_types.py
index f36b4b9a6130..762c203eade4 100644
--- a/lib/galaxy/model/custom_types.py
+++ b/lib/galaxy/model/custom_types.py
@@ -32,7 +32,7 @@ class SafeJsonEncoder(json.JSONEncoder):
     def default(self, obj):
         if isinstance(obj, numpy.int_):
             return int(obj)
-        elif isinstance(obj, numpy.float_):
+        elif isinstance(obj, numpy.float64):
             return float(obj)
         elif isinstance(obj, bytes):
             return unicodify(obj)
diff --git a/pyproject.toml b/pyproject.toml
index 92f64e3672d8..214fb82bbeb3 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -199,7 +199,7 @@ exclude = [
 # Enable: pycodestyle errors (E), Pyflakes (F), flake8-bugbear (B),
 # flake8-comprehensions (C4), flake8-logging-format (G),
 # flake8-implicit-str-concat (ISC) and pyupgrade (UP)
-select = ["E", "F", "B", "C4", "G", "ISC", "UP"]
+select = ["E", "F", "B", "C4", "G", "ISC", "NPY", "UP"]
 # Exceptions:
 # B008 Do not perform function calls in argument defaults (for FastAPI Depends and Body)
 # B9 flake8-bugbear opinionated warnings