Vitess is an open-source database clustering system for MySQL that enables resiliency, scalability, and performance by running multiple instances of MySQL on one or more servers, with a lightweight proxy routing queries to the proper instance. It allows horizontal sharding with minimal application changes, balancing the load across multiple servers, and automatically detects when a MySQL instance goes offline, determining the best candidate to take its place as the primary process to serve queries for a given table. Vitess also improves performance by managing connections between subsystems, establishing lightweight connections to VTGate, which then maps them to a smaller pool of MySQL connections managed by VTTablet, resulting in lower resource utilization. PlanetScale leverages Vitess to offer a serverless database that scales and increases developer velocity, with all the benefits of Vitess infrastructure spun up in mere seconds for developers to start building on.