Building functional patterns for implementing distributed applications

Combining the use of design patterns and distributed functional programming is pointed out as a key factor to produce correct distributed systems running on a cluster of computers. A high degree of adaptability, fault tolerance and scalability are obtained at low development costs. Patterns of recurrent distributed design problems are presented and implemented using the distributed functional language Erlang. The design patterns discussed involve coordination mechanisms of concurrent threads such as guarded suspension or scheduling abstractions. The paper includes some applications of the presented patterns and a small experiment with a clustered XSLT engine.