I want to evaluate the goodness of the trading software using the following criteria: (1) Fast speed for scan many stocks at high frequency; (2) Many indicators and statistics; many charting options... (3) Extensibility - user can write their own complicated indicators/signals/models using either their "easy" language or other C++/Java etc. through API. (4) Output of signals -- allowing us to place order using other brokers, such as IB, etc. Or, if we cannot output signals, and we have to place order within the system, then the brokerage fee is a concern also. (5) This is a huge plus, but I doubt if such trading software exists: open source, you can extend the program yourself... --------------- Any recommendation of such trading softwares? Thanks