diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
new file mode 100644
index 0000000..ae06a3f
--- /dev/null
+++ b/.github/workflows/release.yml
@@ -0,0 +1,29 @@
+on:
+  release:
+    types:
+      - published
+
+name: release
+
+jobs:
+  pypi:
+    name: upload release to PyPI
+    runs-on: ubuntu-latest
+    environment: release
+
+    permissions:
+      # Used to authenticate to PyPI via OIDC.
+      id-token: write
+
+    steps:
+    - uses: actions/checkout@v3
+
+    - uses: actions/setup-python@v4
+      with:
+        python-version: ">= 3.7"
+
+    - name: build
+      run: pipx run build
+
+    - name: publish
+      uses: pypa/gh-action-pypi-publish@release/v1
diff --git a/news/.bugfix b/news/.bugfix
new file mode 100644
index 0000000..35a9e22
--- /dev/null
+++ b/news/.bugfix
@@ -0,0 +1 @@
+Preserve kwargs values in class defintion to ensure to properly create a concrete class with the same attributes as the original one.
diff --git a/src/extendable/main.py b/src/extendable/main.py
index e4d61a2..a0da920 100644
--- a/src/extendable/main.py
+++ b/src/extendable/main.py
@@ -27,6 +27,7 @@ class ExtendableClassDef:
     hierarchy: List["ExtendableClassDef"]
     metaclass: "ExtendableMeta"
     original_cls: Type["ExtendableMeta"]
+    kwargs: Dict[str, Any]
 
     def __init__(
         self,
@@ -34,6 +35,7 @@ def __init__(
         bases: List[Any],
         namespace: Dict[str, Any],
         metaclass: "ExtendableMeta",
+        kwargs: Dict[str, Any],
     ) -> None:
         self.namespace = namespace
         self.name = namespace["__xreg_name__"]
@@ -42,6 +44,7 @@ def __init__(
         self.base_names = namespace["__xreg_base_names__"] or []
         self.hierarchy = [self]
         self.metaclass = metaclass
+        self.kwargs = kwargs
 
     def add_child(self, cls_def: "ExtendableClassDef") -> None:
         self.hierarchy.append(cls_def)
@@ -69,7 +72,11 @@ def clone(self) -> "ExtendableClassDef":
         hierarchy.
         """
         clone = ExtendableClassDef(
-            self.original_name, self.others_bases, self.namespace, self.metaclass
+            self.original_name,
+            self.others_bases,
+            self.namespace,
+            self.metaclass,
+            self.kwargs,
         )
         clone.original_cls = self.original_cls
         return clone
@@ -154,8 +161,9 @@ def _collect_class_def(metacls, name, bases, namespace, extends=None, **kwargs):
         cls_def = ExtendableClassDef(
             original_name=name,
             bases=tuple(other_bases),
-            namespace=namespace,
+            namespace=namespace.copy(),
             metaclass=metacls,
+            kwargs=kwargs,
         )
         __register_class_def__(
             namespace["__module__"],
@@ -191,9 +199,12 @@ def new_method(
                     # ensure that arggs and kwargs are conform to the
                     # initial signature
                     inspect.signature(_initial_func).bind(cls, *args, **kwargs)
-                    return getattr(cls._get_assembled_cls(), _method_name)(
-                        *args, **kwargs
-                    )
+                    try:
+                        return getattr(cls._get_assembled_cls(), _method_name)(
+                            *args, **kwargs
+                        )
+                    except KeyError:
+                        return _initial_func(cls, *args, **kwargs)
 
                 new_method_def = functools.partial(
                     new_method, _method_name=key, _initial_func=func
diff --git a/src/extendable/registry.py b/src/extendable/registry.py
index f88ea77..b80c27c 100644
--- a/src/extendable/registry.py
+++ b/src/extendable/registry.py
@@ -130,7 +130,7 @@ def build_extendable_class(
             extendableClass = types.new_class(
                 simple_name,
                 tuple(bases),
-                kwds={"metaclass": cls_def.metaclass},
+                kwds=dict(class_def.kwargs, metaclass=cls_def.metaclass),
                 exec_body=(
                     lambda ns, namespace=namespace: ns.update(namespace)  # type: ignore
                 ),