diff --git a/pyiron_workflow/channels.py b/pyiron_workflow/channels.py
index 64084eb6..2dccb481 100644
--- a/pyiron_workflow/channels.py
+++ b/pyiron_workflow/channels.py
@@ -144,23 +144,22 @@ def connect(self, *others: Channel) -> None:
                 # so that connection searches run newest to oldest
                 self.connections.insert(0, other)
                 other.connections.insert(0, self)
+            elif isinstance(other, self.connection_partner_type):
+                raise ChannelConnectionError(
+                    f"The channel {other.full_label} ({other.__class__.__name__}"
+                    f") has the correct type "
+                    f"({self.connection_partner_type.__name__}) to connect with "
+                    f"{self.full_label} ({self.__class__.__name__}), but is not "
+                    f"a valid connection. Please check type hints, etc."
+                    f"{other.full_label}.type_hint = {other.type_hint}; "
+                    f"{self.full_label}.type_hint = {self.type_hint}"
+                ) from None
             else:
-                if isinstance(other, self.connection_partner_type):
-                    raise ChannelConnectionError(
-                        f"The channel {other.full_label} ({other.__class__.__name__}"
-                        f") has the correct type "
-                        f"({self.connection_partner_type.__name__}) to connect with "
-                        f"{self.full_label} ({self.__class__.__name__}), but is not "
-                        f"a valid connection. Please check type hints, etc."
-                        f"{other.full_label}.type_hint = {other.type_hint}; "
-                        f"{self.full_label}.type_hint = {self.type_hint}"
-                    ) from None
-                else:
-                    raise TypeError(
-                        f"Can only connect to {self.connection_partner_type.__name__} "
-                        f"objects, but {self.full_label} ({self.__class__.__name__}) "
-                        f"got {other} ({type(other)})"
-                    )
+                raise TypeError(
+                    f"Can only connect to {self.connection_partner_type.__name__} "
+                    f"objects, but {self.full_label} ({self.__class__.__name__}) "
+                    f"got {other} ({type(other)})"
+                )
 
     def disconnect(self, *others: Channel) -> list[tuple[Channel, Channel]]:
         """
diff --git a/pyiron_workflow/nodes/for_loop.py b/pyiron_workflow/nodes/for_loop.py
index af23faba..0bd05847 100644
--- a/pyiron_workflow/nodes/for_loop.py
+++ b/pyiron_workflow/nodes/for_loop.py
@@ -112,15 +112,14 @@ def merge(d1, d2):
         key_index_maps = tuple(
             zipped_index_map(zipped_index) for zipped_index in zipped_generator()
         )
+    elif nested_keys is None and zipped_keys is None:
+        raise ValueError(
+            "At least one of `nested_keys` or `zipped_keys` must be specified."
+        )
     else:
-        if nested_keys is None and zipped_keys is None:
-            raise ValueError(
-                "At least one of `nested_keys` or `zipped_keys` must be specified."
-            )
-        else:
-            raise ValueError(
-                "Received keys to iterate over, but all values had length 0."
-            )
+        raise ValueError(
+            "Received keys to iterate over, but all values had length 0."
+        )
 
     return key_index_maps
 
@@ -393,8 +392,7 @@ def _build_outputs_preview(cls) -> dict[str, Any]:
                 _default,
             ) in cls._body_node_class.preview_inputs().items():
                 if label in cls._zip_on + cls._iter_on:
-                    hint = list if hint is None else list[hint]
-                    preview[label] = hint
+                    preview[label] = list if hint is None else list[hint]
             for label, hint in cls._body_node_class.preview_outputs().items():
                 preview[cls.output_column_map[label]] = (
                     list if hint is None else list[hint]
diff --git a/pyproject.toml b/pyproject.toml
index 84418dd2..d803ad7f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -86,8 +86,25 @@ select = [
     "C4",
     # eradicate
     "ERA",
+    # pylint
+    "PL",
+]
+ignore = [
+    # ignore line-length violations
+    "E501",
+    # Too many arguments in function definition
+    "PLR0913",
+    # Magic value used in comparison
+    "PLR2004",
+    # Import alias does not rename original package
+    "PLC0414",
+    # Too many branches
+    "PLR0912",
+    # Too many statements
+    "PLR0915",
+    # Too many return statements
+    "PLR0911",
 ]
-ignore = ["E501"] #ignore line-length violations
 
 [tool.ruff.lint.per-file-ignores]
 "__init__.py" = ["F401"]  # Ignore unused imports in init files -- we specify APIs this way