Information networks must transmit data over long distances and store it for later retrieval. A quantum network operates in an analogous way but uses signals contained in a quantum system, such as single photons or atoms (1). Although rapid progress in the generation of quantum light provides hope for future realizations of quantum networks, the ability to store photons remains a critical limitation. A number of approaches offer the possibility to store photons (2), but they typically suffer from short storage times, low efficiencies, or large footprints that are incompatible with compact integrated devices. On page 1392 of this issue, Zhong et al. (3) report a major step toward the goal of storing light in a chip-scale atomic memory [sciencemag.org]. They exploit the enhancement of optical cavities to transfer light efficiently to excitations in rare-earth ions. The device fits on a micrometer-sized footprint, allowing storage of light in a very tiny box.