Friday, November 30, 12Even more importantly, consider how even platforms that weren’t originally designed for extensibility cry out for it. When Paul Rademacher reverse-engineered the format of Google’s new mapping app to create the ﬁrst map mashup, housingmaps.com, Googlecould have branded him a “hacker” and tried to shut him down. Instead, they responded by opening up free APIS for developers. Other, more closed platforms were left in the dust, and Google Maps became the preferred mapping platform for the web.Amazon’s ﬁrst venture into web services began the same way. They invited in all the people who were building unauthorized apps against their service, and ﬁgured out how to open them up for innovation.