diff --git a/packages/ludic.inventory/state.ludic b/packages/ludic.inventory/state.ludic
index b8f2aad3..05434235 100644
--- a/packages/ludic.inventory/state.ludic
+++ b/packages/ludic.inventory/state.ludic
@@ -12,15 +12,20 @@ export property ItemChanged {
   after: int = 0
 }
 
+# a change's record comes round again after this many more: far more than a frame makes between drains
+const IV_POOL: int = 512
 export state InventoryState {
   iv_keys: []string = null
   iv_counts: []int = null
   iv_changes: Queue<ItemChanged> = iv_changes__new()
+  iv_pool: []ItemChanged = new []ItemChanged   # the facts' records, made once and taken in turn
+  iv_at: int = 0
 }
 
 # the kinds, by the name each is saved under; the pack starts empty
 export function inv_config(inventory_st: mut InventoryState, keys: []string) -> void {
   inventory_st.iv_keys = keys
+  if len(inventory_st.iv_pool) == 0 { for i in 0 .. IV_POOL { push(inventory_st.iv_pool, new ItemChanged) } }
   inv_clear(inventory_st)
 }
 
diff --git a/packages/ludic.inventory/verbs.ludic b/packages/ludic.inventory/verbs.ludic
index c31c7883..392702e9 100644
--- a/packages/ludic.inventory/verbs.ludic
+++ b/packages/ludic.inventory/verbs.ludic
@@ -3,7 +3,11 @@ function iv_change(inventory_st: mut InventoryState, it: int, after: int) -> voi
   let before = inventory_st.iv_counts[it]
   if before == after { return }
   inventory_st.iv_counts[it] = after
-  let c = new ItemChanged
+  var c: ItemChanged = null
+  if len(inventory_st.iv_pool) > 0 {
+    c = inventory_st.iv_pool[inventory_st.iv_at]
+    inventory_st.iv_at = (inventory_st.iv_at + 1) % len(inventory_st.iv_pool)
+  } else { c = new ItemChanged }
   c.item = it
   c.before = before
   c.after = after