International audienceInternet applications are formed from reusable components all over the software stack. Both on the client and the server side, web-specific libraries and frameworks enable creative developers to wrap up rich applications within very short time. Reuse and modularity are key for liberating creativity and entrepreneurship in the Internet world. However, this bright world has a darker side. The problem is that they participate in creating a massive monoculture, in a way that has never been encountered before. We propose to counter this phenomenon by extending software diversification beyond the operating system level. The way to go is to diversify the different layers, up to the functional code. We have experimented with a...