diff -r 1f40ca07ae1b -r 839fefbdedc7 ucx/list.c
--- a/ucx/list.c	Sat Apr 20 13:01:58 2024 +0200
+++ b/ucx/list.c	Thu May 23 22:35:45 2024 +0200
@@ -47,14 +47,14 @@
 
 static void cx_pl_hack_cmpfunc(struct cx_list_s const *list) {
     // cast away const - this is the hacky thing
-    struct cx_list_s *l = (struct cx_list_s *) list;
+    struct cx_collection_s *l = (struct cx_collection_s*) &list->collection;
     cx_pl_cmpfunc_impl = l->cmpfunc;
     l->cmpfunc = cx_pl_cmpfunc;
 }
 
 static void cx_pl_unhack_cmpfunc(struct cx_list_s const *list) {
     // cast away const - this is the hacky thing
-    struct cx_list_s *l = (struct cx_list_s *) list;
+    struct cx_collection_s *l = (struct cx_collection_s*) &list->collection;
     l->cmpfunc = cx_pl_cmpfunc_impl;
 }
 
@@ -80,11 +80,11 @@
 }
 
 static int cx_pl_insert_iter(
-        struct cx_mut_iterator_s *iter,
+        struct cx_iterator_s *iter,
         void const *elem,
         int prepend
 ) {
-    struct cx_list_s *list = iter->src_handle;
+    struct cx_list_s *list = iter->src_handle.m;
     return list->climpl->insert_iter(iter, &elem, prepend);
 }
 
@@ -115,12 +115,13 @@
     return ptr == NULL ? NULL : *ptr;
 }
 
-static ssize_t cx_pl_find(
-        struct cx_list_s const *list,
-        void const *elem
+static ssize_t cx_pl_find_remove(
+        struct cx_list_s *list,
+        void const *elem,
+        bool remove
 ) {
     cx_pl_hack_cmpfunc(list);
-    ssize_t ret = list->climpl->find(list, &elem);
+    ssize_t ret = list->climpl->find_remove(list, &elem, remove);
     cx_pl_unhack_cmpfunc(list);
     return ret;
 }
@@ -171,7 +172,7 @@
         cx_pl_clear,
         cx_pl_swap,
         cx_pl_at,
-        cx_pl_find,
+        cx_pl_find_remove,
         cx_pl_sort,
         cx_pl_compare,
         cx_pl_reverse,
@@ -179,7 +180,7 @@
 };
 
 void cxListStoreObjects(CxList *list) {
-    list->store_pointer = false;
+    list->collection.store_pointer = false;
     if (list->climpl != NULL) {
         list->cl = list->climpl;
         list->climpl = NULL;
@@ -187,8 +188,8 @@
 }
 
 void cxListStorePointers(CxList *list) {
-    list->item_size = sizeof(void *);
-    list->store_pointer = true;
+    list->collection.elem_size = sizeof(void *);
+    list->collection.store_pointer = true;
     list->climpl = list->cl;
     list->cl = &cx_pointer_list_class;
 }
@@ -208,9 +209,10 @@
     return NULL;
 }
 
-static ssize_t cx_emptyl_find(
-        __attribute__((__unused__)) struct cx_list_s const *list,
-        __attribute__((__unused__)) void const *elem
+static ssize_t cx_emptyl_find_remove(
+        __attribute__((__unused__)) struct cx_list_s *list,
+        __attribute__((__unused__)) void const *elem,
+        __attribute__((__unused__)) bool remove
 ) {
     return -1;
 }
@@ -219,7 +221,7 @@
         __attribute__((__unused__)) struct cx_list_s const *list,
         struct cx_list_s const *other
 ) {
-    if (other->size == 0) return 0;
+    if (other->collection.size == 0) return 0;
     return -1;
 }
 
@@ -233,7 +235,7 @@
         __attribute__((__unused__)) bool backwards
 ) {
     CxIterator iter = {0};
-    iter.src_handle = list;
+    iter.src_handle.c = list;
     iter.index = index;
     iter.base.valid = cx_emptyl_iter_valid;
     return iter;
@@ -248,7 +250,7 @@
         cx_emptyl_noop,
         NULL,
         cx_emptyl_at,
-        cx_emptyl_find,
+        cx_emptyl_find_remove,
         cx_emptyl_noop,
         cx_emptyl_compare,
         cx_emptyl_noop,
@@ -256,14 +258,16 @@
 };
 
 CxList cx_empty_list = {
-        NULL,
-        NULL,
-        0,
-        0,
-        NULL,
-        NULL,
-        NULL,
-        false,
+        {
+                NULL,
+                NULL,
+                0,
+                0,
+                NULL,
+                NULL,
+                NULL,
+                false
+        },
         &cx_empty_list_class,
         NULL
 };
@@ -282,7 +286,7 @@
 ) {
     if (
         // if one is storing pointers but the other is not
-        (list->store_pointer ^ other->store_pointer) ||
+        (list->collection.store_pointer ^ other->collection.store_pointer) ||
 
         // if one class is wrapped but the other is not
         ((list->climpl == NULL) ^ (other->climpl == NULL)) ||
@@ -292,13 +296,13 @@
          (other->climpl != NULL ? other->climpl->compare : other->cl->compare))
     ) {
         // lists are definitely different - cannot use internal compare function
-        if (list->size == other->size) {
-            CxIterator left = cxListIterator(list);
-            CxIterator right = cxListIterator(other);
-            for (size_t i = 0; i < list->size; i++) {
+        if (list->collection.size == other->collection.size) {
+            CxIterator left = list->cl->iterator(list, 0, false);
+            CxIterator right = other->cl->iterator(other, 0, false);
+            for (size_t i = 0; i < list->collection.size; i++) {
                 void *leftValue = cxIteratorCurrent(left);
                 void *rightValue = cxIteratorCurrent(right);
-                int d = list->cmpfunc(leftValue, rightValue);
+                int d = list->collection.cmpfunc(leftValue, rightValue);
                 if (d != 0) {
                     return d;
                 }
@@ -307,7 +311,7 @@
             }
             return 0;
         } else {
-            return list->size < other->size ? -1 : 1;
+            return list->collection.size < other->collection.size ? -1 : 1;
         }
     } else {
         // lists are compatible
@@ -315,28 +319,20 @@
     }
 }
 
-CxMutIterator cxListMutIteratorAt(
+CxIterator cxListMutIteratorAt(
         CxList *list,
         size_t index
 ) {
     CxIterator it = list->cl->iterator(list, index, false);
     it.base.mutating = true;
-
-    // we know the iterators share the same memory layout
-    CxMutIterator iter;
-    memcpy(&iter, &it, sizeof(CxMutIterator));
-    return iter;
+    return it;
 }
 
-CxMutIterator cxListMutBackwardsIteratorAt(
+CxIterator cxListMutBackwardsIteratorAt(
         CxList *list,
         size_t index
 ) {
     CxIterator it = list->cl->iterator(list, index, true);
     it.base.mutating = true;
-
-    // we know the iterators share the same memory layout
-    CxMutIterator iter;
-    memcpy(&iter, &it, sizeof(CxMutIterator));
-    return iter;
+    return it;
 }