A massive-scale X-ray free-electron laser (XFEL) enables tracking structural and electron dynamics in novel systems, including fusion materials, semiconductors, batteries, and catalysis. It produces ultrashort X-ray pulses that can record the movements of atoms and electrons. These instruments can detect the smallest change in material structure caused by defects and other influences. The high repetition rate of these bright X-ray bursts can reach up to 1 million shots per second with 35-million-pixel cameras.  The acquired multidimensional datasets contain rich physical information about the fastest microscopic movements of electrons and atoms, which can help identify defects in materials.…