This is a web app meant to help people test trading strategies on historical data so they can understand how their portfolio will stack up against the market before they start using real capital.
The backtester can graph the fluctuations in value of any submitted portfolio over a span of time. Furthermore, it can analyze any given portfolio against the market, using a host of ratios such as beta, Sharpe, and Treynor, so the user has a better idea of the risk return characteristics of their portfolio as compared to the S&P 500. The backtester also employs some of its own technical analysis tools like bollinger bands to help make selections.
As of now, all the major scripts in backtester are finished. However the web app is still being built. Any individual script can be downloaded and run, provided that appropriate stock data is also supplied.
Future additions will include a stock screener feature to help users build portfolios tailored to their risk preference and investing style. In the future, there will also be machine learning algorithms put in place so that the app can actually predict future prices of a submitted portfolio based on its historic values. A much more advanced form of this could one day scrub the internet for news relating to that company and look for keywords and phrases such as "acquisition" or "regulations" that could directly impact the stock price in the future.