diff --git a/crowdkit/aggregation/utils.py b/crowdkit/aggregation/utils.py
index 7c706c0..358c16a 100644
--- a/crowdkit/aggregation/utils.py
+++ b/crowdkit/aggregation/utils.py
@@ -191,7 +191,7 @@ def converter(series: "pd.Series[Any]") -> "pd.Series[Any]":
         series.name = name
         return series
 
-    return attr.ib(init=False, converter=converter, on_setattr=attr.setters.convert)
+    return attr.ib(init=False, converter=converter, on_setattr=attr.setters.convert)  # type: ignore[no-any-return]
 
 
 def add_skills_to_data(
diff --git a/pyproject.toml b/pyproject.toml
index 64a61f0..9e0c8f8 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -28,14 +28,14 @@ classifiers = [
 ]
 requires-python = ">= 3.8"
 dependencies = [
-    "attrs ~= 23.2",
+    "attrs",
     "nltk",
     "numpy",
     "pandas >= 1.1.0",
     "pyarrow",
     "scikit-learn",
     "tqdm",
-    "transformers"
+    "transformers",
 ]
 dynamic = ["version"]