V8 provides the ability to capture a snapshot out of an initialized heap and rehydrate a heap from the snapshot instead of initializing it from scratch. One of the most important use cases of this feature is to improve the startup performance of an application built on top of V8. In this talk we are going to take a look at the integration of the V8 startup snapshots in Node.js, how the snapshots have been used to speed up the startup of Node.js core, and how user-land startup snapshots can be used to speed up the startup of user applications.