The IB DDE is a free and easy tool to bulk upload trades into TWS. You can code AmiBroker to format orders to quickly insert into the DDE and send.

My own API not only uploads the trades quickly into TWS, but also manages the positions, which is especially important when trading US stocks on leverage.

US markets have Pattern Day Trader margin rates which allows an account additional leverage during the day. Normal overnight margin is 50%, allowing a $50k account to be traded as a $100k account, Pattern Day Trader margin allows that $50k account trade up to $200k – BUT ONLY FOR THE DAY. It must return to $100k or less overnight.

If you place a large amount of orders, say 80, and only want 20 filled, then you are at risk of a large decline which will execute more than the wanted amount and in turn you will potentially expose yourself to a margin call and extensive losses. Whilst IB will close excessive positions out automatically, if the market continues lower during the day, and closes at or near its lows, then you will suffer large realised losses.

My API manages exposure in two ways:

(1) It will limit the number of open positions to the user specific amount, i.e. 20.
(2) If for some reason, like a huge opening gap, you get more than the wanted fills, the API will automatically and instantly close excess positions and bring your exposure back to the wanted amount. This occurs within 2 seconds of the initial fill so any losses are very minimal.

The API is an additional expense of A$440. You can email me should the IB DDE is not sufficient for your purposes.

ADD:

My API is designed to place LIMIT orders on the buy side only. It does not place any other type of order nor the short side.

Should you want additional features, such as different order types or profit targets, I can supply the name of the developer and you can have a custom API built.