The EU-funded EXA4MIND project plans to build an extreme data platform that brings together data storage systems and powerful computing infrastructures. To this end, researchers will set up a unique, modular extreme data database and advanced analytics on supercomputers powered by artificial intelligence and machine learning. These technologies should help unlock data collection from heterogeneous sources, automatic data harmonisation and annotation on the fly. At its core, EXA4MIND is driven by four application cases in the fields of molecular dynamics, autonomous driving, smart agri/viticulture and health/social big data.