An atlas of Drosophila embryonic development at single-cell resolution is published in Science this week, representing a new resource for its study. To build the atlas, a team led by scientists from the University of Washington used various sequencing techniques to profile chromatin accessibility at almost 1 million nuclei and gene expression in half a million nuclei from 11 overlapping windows spanning the entirety of Drosophila embryogenesis. Leveraging developmental asynchronicity within embryo collections, they further used deep neural network-based predictive modeling to precisely predict the developmental age of each nucleus, resulting in continuous, multimodal views of molecular and cellular transitions in absolute time. "With these data, the dynamics of enhancer usage and gene expression can be explored within and across lineages at the scale of minutes, including for precise transitions like zygotic genome activation," the study's authors write. "Although larval stages remain insufficiently profiled, we hope that these data and methods, together with the recently released large-scale adult atlas, bring us closer to the community-wide goal of a multi-modal Drosophila atlas spanning a continuum from zygote to adulthood."