International audienceWith the recent widespread adoption of service-oriented architecture, the dynamic composition of services is now a crucial issue in the area of distributed computing. The coordination and execution of composite Web services are today typically conducted by heavyweight centralized workflow engines, leading to an increasing probability of processing and communication bottlenecks and failures. In addition, centralization induces higher deployment costs, such as the computing infrastructure to support the workflow engine, which is not affordable for a large number of small businesses and end-users. In a world where platforms are more and more dynamic and elastic as promised by cloud computing, decentralized and dynamic int...