Announcing Coin Trader, an open-source, Java-based backend engine for algorithmically trading cryptocurrencies.  It integrates with existing libraries for market data and order execution, plus it provides persistence and an event-based architecture for backtesting, algorithm design, and live trading.  It is not quite ready for live trading, but with a few additional contributions we will have a robust algo trading platform.  See the github site for documentation.

https://github.com/timolson/cointrader

Tim Olson
http://linkedin.com/in/olsontim