diff -r 488178e3e328 -r 9b5948aa5b90 ucx/cx/list.h
--- a/ucx/cx/list.h	Sun Nov 30 18:15:46 2025 +0100
+++ b/ucx/cx/list.h	Sun Nov 30 18:17:49 2025 +0100
@@ -170,6 +170,12 @@
     void (*reverse)(struct cx_list_s *list);
 
     /**
+     * Optional member function for changing the capacity.
+     * If the list does not support overallocation, this can be set to @c NULL.
+     */
+    int (*change_capacity)(struct cx_list_s *list, size_t new_capacity);
+
+    /**
      * Member function for returning an iterator pointing to the specified index.
      */
     struct cx_iterator_s (*iterator)(const struct cx_list_s *list, size_t index, bool backward);
@@ -961,6 +967,226 @@
 CX_EXPORT void cxListFree(CxList *list);
 
 
+/**
+ * Performs a deep clone of one list into another.
+ *
+ * If the destination list already contains elements, the cloned elements
+ * are appended to that list.
+ *
+ * @attention If the cloned elements need to be destroyed by a destructor
+ * function, you must make sure that the destination list also uses this
+ * destructor function.
+ *
+ * @param dst the destination list
+ * @param src the source list
+ * @param clone_func the clone function for the elements
+ * @param clone_allocator the allocator that is passed to the clone function
+ * @param data optional additional data that is passed to the clone function
+ * @retval zero when all elements were successfully cloned
+ * @retval non-zero when an allocation error occurred
+ * @see cxListCloneSimple()
+ */
+cx_attr_nonnull_arg(1, 2, 3)
+CX_EXPORT int cxListClone(CxList *dst, const CxList *src,
+        cx_clone_func clone_func, const CxAllocator *clone_allocator, void *data);
+
+/**
+ * Clones elements from a list only if they are not present in another list.
+ *
+ * If the @p minuend does not contain duplicates, this is equivalent to adding
+ * the set difference to the destination list.
+ *
+ * This function is optimized for the case when both the @p minuend and the
+ * @p subtrahend are sorted.
+ *
+ * @param dst the destination list
+ * @param minuend the list to subtract elements from
+ * @param subtrahend the elements that shall be subtracted
+ * @param clone_func the clone function for the elements
+ * @param clone_allocator the allocator that is passed to the clone function
+ * @param data optional additional data that is passed to the clone function
+ * @retval zero when the elements were successfully cloned
+ * @retval non-zero when an allocation error occurred
+ * @see cxListDifferenceSimple()
+ */
+cx_attr_nonnull_arg(1, 2, 3, 4)
+CX_EXPORT int cxListDifference(CxList *dst,
+        const CxList *minuend, const CxList *subtrahend,
+        cx_clone_func clone_func, const CxAllocator *clone_allocator, void *data);
+
+/**
+ * Clones elements from a list only if they are also present in another list.
+ *
+ * This function is optimized for the case when both the @p src and the
+ * @p other list are sorted.
+ *
+ * If the destination list already contains elements, the intersection is appended
+ * to that list.
+ *
+ * @param dst the destination list
+ * @param src the list to clone the elements from
+ * @param other the list to check the elements for existence
+ * @param clone_func the clone function for the elements
+ * @param clone_allocator the allocator that is passed to the clone function
+ * @param data optional additional data that is passed to the clone function
+ * @retval zero when the elements were successfully cloned
+ * @retval non-zero when an allocation error occurred
+ * @see cxListIntersectionSimple()
+ */
+cx_attr_nonnull_arg(1, 2, 3, 4)
+CX_EXPORT int cxListIntersection(CxList *dst, const CxList *src, const CxList *other,
+        cx_clone_func clone_func, const CxAllocator *clone_allocator, void *data);
+
+/**
+ * Performs a deep clone of one list into another, skipping duplicates.
+ *
+ * This function is optimized for the case when both the @p src and the
+ * @p other list are sorted.
+ * In that case, the union will also be sorted.
+ *
+ * If the destination list already contains elements, the union is appended
+ * to that list. In that case the destination is not necessarily sorted.
+ *
+ * @param dst the destination list
+ * @param src the primary source list
+ * @param other the other list, where elements are only cloned from
+ * when they are not in @p src
+ * @param clone_func the clone function for the elements
+ * @param clone_allocator the allocator that is passed to the clone function
+ * @param data optional additional data that is passed to the clone function
+ * @retval zero when the elements were successfully cloned
+ * @retval non-zero when an allocation error occurred
+ * @see cxListUnionSimple()
+ */
+cx_attr_nonnull_arg(1, 2, 3, 4)
+CX_EXPORT int cxListUnion(CxList *dst, const CxList *src, const CxList *other,
+        cx_clone_func clone_func, const CxAllocator *clone_allocator, void *data);
+
+/**
+ * Performs a shallow clone of one list into another.
+ *
+ * This function uses the default allocator, if needed, and performs
+ * shallow clones with @c memcpy().
+ *
+ * If the destination list already contains elements, the cloned elements
+ * are appended to that list.
+ *
+ * @attention If the cloned elements need to be destroyed by a destructor
+ * function, you must make sure that the destination list also uses this
+ * destructor function.
+ *
+ * @param dst the destination list
+ * @param src the source list
+ * @retval zero when all elements were successfully cloned
+ * @retval non-zero when an allocation error occurred
+ * @see cxListClone()
+ */
+cx_attr_nonnull
+CX_EXPORT int cxListCloneSimple(CxList *dst, const CxList *src);
+
+/**
+ * Clones elements from a list only if they are not present in another list.
+ *
+ * This function uses the default allocator, if needed, and performs
+ * shallow clones with @c memcpy().
+ *
+ * If the @p minuend does not contain duplicates, this is equivalent to adding
+ * the set difference to the destination list.
+ *
+ * This function is optimized for the case when both the @p minuend and the
+ * @p subtrahend are sorted.
+ *
+ * @param dst the destination list
+ * @param minuend the list to subtract elements from
+ * @param subtrahend the elements that shall be subtracted
+ * @retval zero when the elements were successfully cloned
+ * @retval non-zero when an allocation error occurred
+ * @see cxListDifference()
+ */
+cx_attr_nonnull
+CX_EXPORT int cxListDifferenceSimple(CxList *dst,
+        const CxList *minuend, const CxList *subtrahend);
+
+/**
+ * Clones elements from a list only if they are also present in another list.
+ *
+ * This function uses the default allocator, if needed, and performs
+ * shallow clones with @c memcpy().
+ *
+ * This function is optimized for the case when both the @p src and the
+ * @p other list are sorted.
+ *
+ * If the destination list already contains elements, the intersection is appended
+ * to that list.
+ *
+ * @param dst the destination list
+ * @param src the list to clone the elements from
+ * @param other the list to check the elements for existence
+ * @retval zero when the elements were successfully cloned
+ * @retval non-zero when an allocation error occurred
+ * @see cxListIntersection()
+ */
+cx_attr_nonnull
+CX_EXPORT int cxListIntersectionSimple(CxList *dst, const CxList *src, const CxList *other);
+
+/**
+ * Performs a deep clone of one list into another, skipping duplicates.
+ *
+ * This function uses the default allocator, if needed, and performs
+ * shallow clones with @c memcpy().
+ *
+ * This function is optimized for the case when both the @p src and the
+ * @p other list are sorted.
+ * In that case, the union will also be sorted.
+ *
+ * If the destination list already contains elements, the union is appended
+ * to that list. In that case the destination is not necessarily sorted.
+ *
+ * @param dst the destination list
+ * @param src the primary source list
+ * @param other the other list, where elements are only cloned from
+ * when they are not in @p src
+ * @retval zero when the elements were successfully cloned
+ * @retval non-zero when an allocation error occurred
+ * @see cxListUnion()
+ */
+cx_attr_nonnull
+CX_EXPORT int cxListUnionSimple(CxList *dst, const CxList *src, const CxList *other);
+
+/**
+ * Asks the list to reserve enough memory for a given total number of elements.
+ *
+ * List implementations are free to choose if reserving memory upfront makes
+ * sense.
+ * For example, array-based implementations usually do support reserving memory
+ * for additional elements while linked lists usually don't.
+ *
+ * @note When the requested capacity is smaller than the current size,
+ * this function returns zero without performing any action.
+ *
+ * @param list the list
+ * @param capacity the expected total number of elements
+ * @retval zero on success or when overallocation is not supported
+ * @retval non-zero when an allocation error occurred
+ * @see cxListShrink()
+ */
+cx_attr_nonnull
+CX_EXPORT int cxListReserve(CxList *list, size_t capacity);
+
+/**
+ * Advises the list to free any overallocated memory.
+ *
+ * Lists that do not support overallocation simply return zero.
+ *
+ * This function usually returns zero, except for very special and custom
+ * list and/or allocator implementations where freeing memory can fail.
+ *
+ * @param list the list
+ * @return usually zero
+ */
+cx_attr_nonnull
+CX_EXPORT int cxListShrink(CxList *list);
+
 #ifdef __cplusplus
 } // extern "C"
 #endif