diff --git a/Facepunch.Steamworks/Generated/Interfaces/ISteamInventory.cs b/Facepunch.Steamworks/Generated/Interfaces/ISteamInventory.cs
index 1de4aaa..d33b118 100644
--- a/Facepunch.Steamworks/Generated/Interfaces/ISteamInventory.cs
+++ b/Facepunch.Steamworks/Generated/Interfaces/ISteamInventory.cs
@@ -236,13 +236,13 @@ namespace Steamworks
 		#region FunctionMeta
 		[UnmanagedFunctionPointer( CallingConvention.ThisCall )]
 		[return: MarshalAs( UnmanagedType.I1 )]
-		private delegate bool FExchangeItems( IntPtr self, ref SteamInventoryResult_t pResultHandle, ref InventoryDefId pArrayGenerate, ref uint punArrayGenerateQuantity, uint unArrayGenerateLength, ref InventoryItemId pArrayDestroy, ref uint punArrayDestroyQuantity, uint unArrayDestroyLength );
+		private delegate bool FExchangeItems( IntPtr self, ref SteamInventoryResult_t pResultHandle, [In,Out] InventoryDefId[]  pArrayGenerate, [In,Out] uint[]  punArrayGenerateQuantity, uint unArrayGenerateLength, [In,Out] InventoryItemId[]  pArrayDestroy, [In,Out] uint[]  punArrayDestroyQuantity, uint unArrayDestroyLength );
 		private FExchangeItems _ExchangeItems;
 		
 		#endregion
-		internal bool ExchangeItems( ref SteamInventoryResult_t pResultHandle, ref InventoryDefId pArrayGenerate, ref uint punArrayGenerateQuantity, uint unArrayGenerateLength, ref InventoryItemId pArrayDestroy, ref uint punArrayDestroyQuantity, uint unArrayDestroyLength )
+		internal bool ExchangeItems( ref SteamInventoryResult_t pResultHandle, [In,Out] InventoryDefId[]  pArrayGenerate, [In,Out] uint[]  punArrayGenerateQuantity, uint unArrayGenerateLength, [In,Out] InventoryItemId[]  pArrayDestroy, [In,Out] uint[]  punArrayDestroyQuantity, uint unArrayDestroyLength )
 		{
-			return _ExchangeItems( Self, ref pResultHandle, ref pArrayGenerate, ref punArrayGenerateQuantity, unArrayGenerateLength, ref pArrayDestroy, ref punArrayDestroyQuantity, unArrayDestroyLength );
+			return _ExchangeItems( Self, ref pResultHandle, pArrayGenerate, punArrayGenerateQuantity, unArrayGenerateLength, pArrayDestroy, punArrayDestroyQuantity, unArrayDestroyLength );
 		}
 		
 		#region FunctionMeta
@@ -283,13 +283,13 @@ namespace Steamworks
 		#region FunctionMeta
 		[UnmanagedFunctionPointer( CallingConvention.ThisCall )]
 		[return: MarshalAs( UnmanagedType.I1 )]
-		private delegate bool FTradeItems( IntPtr self, ref SteamInventoryResult_t pResultHandle, SteamId steamIDTradePartner, ref InventoryItemId pArrayGive, ref uint pArrayGiveQuantity, uint nArrayGiveLength, ref InventoryItemId pArrayGet, ref uint pArrayGetQuantity, uint nArrayGetLength );
+		private delegate bool FTradeItems( IntPtr self, ref SteamInventoryResult_t pResultHandle, SteamId steamIDTradePartner, [In,Out] InventoryItemId[]  pArrayGive, [In,Out] uint[]  pArrayGiveQuantity, uint nArrayGiveLength, [In,Out] InventoryItemId[]  pArrayGet, [In,Out] uint[]  pArrayGetQuantity, uint nArrayGetLength );
 		private FTradeItems _TradeItems;
 		
 		#endregion
-		internal bool TradeItems( ref SteamInventoryResult_t pResultHandle, SteamId steamIDTradePartner, ref InventoryItemId pArrayGive, ref uint pArrayGiveQuantity, uint nArrayGiveLength, ref InventoryItemId pArrayGet, ref uint pArrayGetQuantity, uint nArrayGetLength )
+		internal bool TradeItems( ref SteamInventoryResult_t pResultHandle, SteamId steamIDTradePartner, [In,Out] InventoryItemId[]  pArrayGive, [In,Out] uint[]  pArrayGiveQuantity, uint nArrayGiveLength, [In,Out] InventoryItemId[]  pArrayGet, [In,Out] uint[]  pArrayGetQuantity, uint nArrayGetLength )
 		{
-			return _TradeItems( Self, ref pResultHandle, steamIDTradePartner, ref pArrayGive, ref pArrayGiveQuantity, nArrayGiveLength, ref pArrayGet, ref pArrayGetQuantity, nArrayGetLength );
+			return _TradeItems( Self, ref pResultHandle, steamIDTradePartner, pArrayGive, pArrayGiveQuantity, nArrayGiveLength, pArrayGet, pArrayGetQuantity, nArrayGetLength );
 		}
 		
 		#region FunctionMeta
diff --git a/Facepunch.Steamworks/SteamInventory.cs b/Facepunch.Steamworks/SteamInventory.cs
index 743adcc..f861fbe 100644
--- a/Facepunch.Steamworks/SteamInventory.cs
+++ b/Facepunch.Steamworks/SteamInventory.cs
@@ -167,5 +167,26 @@ namespace Steamworks
 			return await InventoryResult.GetAsync( sresult );
 		}
 
+		/// <summary>
+		/// Crafting! Uses the passed items to buy the target item.
+		/// You need to have set up the appropriate exchange rules in your item
+		/// definitions. This assumes all the items passed in aren't stacked.
+		/// </summary>
+		static async Task<InventoryResult?> CraftItem( InventoryItem[] list, InventoryDef target )
+		{
+			var sresult = default( SteamInventoryResult_t );
+
+			var give = new InventoryDefId[] { target.Id };
+			var givec = new uint[] { 1 };
+
+			var sell = list.Select( x => x.Id ).ToArray();
+			var sellc = list.Select( x => (uint)1 ).ToArray();
+
+			if ( !Internal.ExchangeItems( ref sresult, give, givec, 1, sell, sellc, (uint)sell.Length ) )
+				return null;
+
+			return await InventoryResult.GetAsync( sresult );
+		}
+
 	}
 }
\ No newline at end of file
diff --git a/Generator/CodeWriter/Types/BaseType.cs b/Generator/CodeWriter/Types/BaseType.cs
index 805981a..c10d6be 100644
--- a/Generator/CodeWriter/Types/BaseType.cs
+++ b/Generator/CodeWriter/Types/BaseType.cs
@@ -67,14 +67,14 @@ internal class BaseType
 			if ( VarName == "psteamIDClans" ) return true;
 			if ( VarName == "pScoreDetails" ) return true;
 			if ( VarName == "prgUsers" ) return true;
-			if ( VarName == "punArrayQuantity" ) return true;
-			if ( VarName == "pArrayItemDefs" ) return true;
 			if ( VarName == "pBasePrices" ) return true;
 			if ( VarName == "pCurrentPrices" ) return true;
 			if ( VarName == "pItemDefIDs" ) return true;
 			if ( VarName == "pDetails" && Func == "GetDownloadedLeaderboardEntry" ) return true;
 			if ( VarName == "pData" && NativeType.EndsWith( "*" ) && Func.StartsWith( "GetGlobalStatHistory" ) ) return true;
 			if ( NativeType.EndsWith( "**" ) ) return true;
+			if ( VarName.StartsWith( "pArray" ) ) return true;
+			if ( VarName.StartsWith( "punArray" ) ) return true;
 
 			if ( NativeType.EndsWith( "*" ) )
 			{