diff --git a/dbzero/dbzero/enum.py b/dbzero/dbzero/enum.py
index efd12b62..2a150c06 100644
--- a/dbzero/dbzero/enum.py
+++ b/dbzero/dbzero/enum.py
@@ -7,10 +7,10 @@
 
 
 @overload
-def enum(cls: str, values: List[str], *, prefix: Optional[str] = None) -> EnumType: ...
+def enum(cls: str, values: List[str]) -> EnumType: ...
 
 @overload 
-def enum(*, values: List[str], prefix: Optional[str] = None) -> EnumType: ...
+def enum(*, values: List[str]) -> EnumType: ...
 
 @overload
 def enum(cls: type) -> EnumType: ...
@@ -30,10 +30,6 @@ def enum(cls: Optional[Union[str, type]] = None, *args: Any, **kwargs: Any) -> E
     values : list of str
         A list of unique string names for the enum members. The order of values 
         is preserved.
-    prefix : str, optional
-        Scopes the enum definition to a specific data prefix. If None (default), 
-        the enum is defined in the prefix that is active at the time of creation. 
-        This allows for creating data-model-specific enums.
 
     Returns
     -------
diff --git a/src/dbzero/bindings/python/Memo.cpp b/src/dbzero/bindings/python/Memo.cpp
index 7e063870..b81c79e9 100644
--- a/src/dbzero/bindings/python/Memo.cpp
+++ b/src/dbzero/bindings/python/Memo.cpp
@@ -206,7 +206,12 @@ namespace db0::python
         PY_API_FUNC
         // destroy associated db0 Object instance
         memo_obj->destroy();
-        Py_TYPE(memo_obj)->tp_free((PyObject*)memo_obj);
+        if (Py_IsInitialized())
+        {
+            // Skip deallocation during/after Python finalization
+            // Python Garbage Collector might be finalized (i.e. destroyed) at this point
+            Py_TYPE(memo_obj)->tp_free((PyObject*)memo_obj);
+        }
     }
 
     template <typename MemoImplT>
diff --git a/src/dbzero/bindings/python/PyToolkit.cpp b/src/dbzero/bindings/python/PyToolkit.cpp
index f24a9966..c25db036 100644
--- a/src/dbzero/bindings/python/PyToolkit.cpp
+++ b/src/dbzero/bindings/python/PyToolkit.cpp
@@ -740,6 +740,12 @@ namespace db0::python
             return {};            
         } 
 
+        if (!Py_IsInitialized()) {
+            // Simply return the lock after python instance was finalized
+            // This is safe because fixture threads should be stopped at this point
+            return SafeRLock(m_api_mutex);
+        }
+
         // unlock GIL while waiting for the API mutex
         PyThreadState *__save = PyEval_SaveThread();
         auto result = SafeRLock(m_api_mutex);
diff --git a/src/dbzero/object_model/value/Member.hpp b/src/dbzero/object_model/value/Member.hpp
index 1db72582..f865c165 100644
--- a/src/dbzero/object_model/value/Member.hpp
+++ b/src/dbzero/object_model/value/Member.hpp
@@ -78,7 +78,8 @@ namespace db0::object_model
     {
         // create member function pointer
         using UnloadMemberFunc = typename LangToolkit::ObjectSharedPtr (*)(db0::swine_ptr<Fixture> &, Value, unsigned int, AccessFlags);
-        static std::vector<UnloadMemberFunc> unload_member_functions;
+        static auto *unload_member_functions_ptr = new std::vector<UnloadMemberFunc>();
+        auto &unload_member_functions = *unload_member_functions_ptr;
         if (unload_member_functions.empty()) {
             registerUnloadMemberFunctions<LangToolkit>(unload_member_functions);
         }
@@ -101,7 +102,8 @@ namespace db0::object_model
     {
         // create member function pointer
         using UnrefMemberFunc = void (*)(db0::swine_ptr<Fixture> &, Value);
-        static std::vector<UnrefMemberFunc> unref_member_functions;
+        static auto *unref_member_functions_ptr = new std::vector<UnrefMemberFunc>();
+        auto &unref_member_functions = *unref_member_functions_ptr;
         if (unref_member_functions.empty()) {
             registerUnrefMemberFunctions<LangToolkit>(unref_member_functions);
         }
diff --git a/src/dbzero/workspace/FixtureThreads.cpp b/src/dbzero/workspace/FixtureThreads.cpp
index 3b2b121a..c5aba1b5 100644
--- a/src/dbzero/workspace/FixtureThreads.cpp
+++ b/src/dbzero/workspace/FixtureThreads.cpp
@@ -210,7 +210,7 @@ namespace db0
         // otherwise it may deadlock on trying to invoke API calls from auto-commit 
         // (e.g. instance destruction triggered by LangCache::clear)
         auto __api_lock = LangToolkit::lockApi();
-        // // NOTE: since this a separate thread, we must acuire the language interpreter's lock (where required)
+        // NOTE: since this a separate thread, we must acquire the language interpreter's lock (where required)
         auto lang_lock = LangToolkit::ensureLocked();
         auto callbacks = fixture.onAutoCommit();
         if (!callbacks.empty()) {