diff --git a/IO.lua b/IO.lua
index 20174f2..62e636f 100644
--- a/IO.lua
+++ b/IO.lua
@@ -18,39 +18,44 @@ local function get_num_stacks(total_items)
     return math.ceil(total_items / 64)
 end
 
-while true do
-    local stacks_stored = d.map(d.filter(chest.list(), function(x) return x ~= nil end), w.to_wyvern_item)
-    local items_stored = w.collate_stacks(stacks_stored)
-
-    local function get_item_count(ii)
-        return (items_stored[ii] or {count = 0}).count
-    end
-
-    for item_name, quantity_desired in pairs(conf.items) do
-        local quantity_stocked = get_item_count(item_name)
-        if quantity_desired > quantity_stocked then -- if we have fewer items than are desired, extract some from store
-            local request = w.string_to_item(item_name)
-            request.type = "extract"
-            request.destination_inventory = conf.chest
-            local result = w.unwrap(w.query_by_type("storage", request), "extracting items")
-            print("Moved", result.moved, item_name, "from storage.")
+local function main()
+    while true do
+        local stacks_stored = d.map(d.filter(chest.list(), function(x) return x ~= nil end), w.to_wyvern_item)
+        local items_stored = w.collate_stacks(stacks_stored)
+        
+        local function get_item_count(ii)
+            return (items_stored[ii] or {count = 0}).count
         end
-    end
-
-    for slot, item in pairs(stacks_stored) do
-        local ii = w.get_internal_identifier(item)
-        local stored = get_item_count(ii)
-        local wanted = 0
-        if conf.items[ii] then wanted = conf.items[ii] + 1 end
-        if (get_num_stacks(stored) * 64) >= wanted then -- if item is not in want list or we have too many, send it back to storage
-            local result = w.unwrap(w.query_by_type("storage", {
-                type = "insert",
-                from_inventory = conf.chest,
-                from_slot = slot
-            }), "inserting items")
-            print("Moved", result.moved, ii, "to storage.")
+        
+        for item_name, quantity_desired in pairs(conf.items) do
+            local quantity_stocked = get_item_count(item_name)
+            if quantity_desired > quantity_stocked then -- if we have fewer items than are desired, extract some from store
+                local request = w.string_to_item(item_name)
+                request.type = "extract"
+                request.destination_inventory = conf.chest
+                local result = w.unwrap(w.query_by_type("storage", request), "extracting items")
+                print("Moved", result.moved, item_name, "from storage.")
+            end
         end
+        
+        for slot, item in pairs(stacks_stored) do
+            local ii = w.get_internal_identifier(item)
+            local stored = get_item_count(ii)
+            local wanted = 0
+            if conf.items[ii] then wanted = conf.items[ii] + 1 end
+            if (get_num_stacks(stored) * 64) >= wanted then -- if item is not in want list or we have too many, send it back to storage
+                local result = w.unwrap(w.query_by_type("storage", {
+                    type = "insert",
+                    from_inventory = conf.chest,
+                    from_slot = slot
+                }), "inserting items")
+                print("Moved", result.moved, ii, "to storage.")
+            end
+        end
+        
+        sleep(conf.sleep_time)
     end
+end
 
-    sleep(conf.sleep_time)
-end
\ No newline at end of file
+local ok, err = pcall(main)
+print(w.errors.format(err))
\ No newline at end of file