Investigating the Evolution of Web API Cooperative Communities in the Mashup Ecosystem

In the mashup ecosystem, Web APIs often form cooperative communities which evolve with time. Understanding how these communities form and evolve with time is very important to help develop strategies for improving ecosystems of Web APIs. This paper empirically studies the evolution of Web API cooperative communities based on the data of Web APIs and mashups from Programmable Web. It is found that 20% of Web APIs account for half of the connections in their communities. The Web API communities identified in terms of mashups seem to be stable. Every two years, there is a 27% growth in the number of new communities, 10% dissolve, 30% tend to expand, while 5% become smaller. It is a key stage when a Web API community becomes medium sized because in this stage, there is a high probability that a Web API community reduces its size or even dissolves.