Technology is the main driver of human progress. Digital transformation is revolutionizing countless sectors, dramatically changing the lifestyle of people around the world.Snap4City is an open source framework and a living lab, providing tools to quickly create a large range of smart city applications exploiting heterogeneous data coming from Helsinki, Antwerp, Florence, Tuscany) and enabling services for stakeholders by IOT/IOE, data analytics and big data technologies. Snap4City applications support multiple paradigms as data driven, stream and batch processing, thus allowing to create dashboards, IOT applications, Web and Mobile applications, Data Analytics, etc. We have decided to launch this hackathon because we are constantly looking for innovative ways to live more responsibly and we think that a project on sustainability, sharing, collaboration, could concretely improve people's lives and help build the planet in which we would like to live. Are you creative? Do you love technology? Do you want to improve people's lives? Do you want a more sustainable future? Find out more about our challenges and register! Key points The Snap4City Hack is a big hackathon on the topics of Smart City and IOT. The hackathon is taking place from January 21 to March 15, All the projects will be hosted by Snap4City.org. All submissions must be developed and/or uploaded on Snap4City.org. In order to take part to the hackathon, you have to register first on Snap4City and then sign up to the Hackathon by using the above link. The early registration on Snap4City will get you at role Manager, while Hackathon participants will be immediatly passed at AreaManager to provide them the access to the needed development tools. The great thing is that you can register and choose to run for Helsinki or Antwerp, using their corresponding data.