To build a high-performance data app with Snowflake as a Data Source, first connect to your Snowflake account and create a user, role, and warehouse for Propel in the account. Then, create a Snowflake Data Source inside Propel's Console by entering your Snowflake connection details. Next, sync a table from Snowflake by creating a Data Pool, which will start the sync process and create an optimized mirror of the table. After that, define Metrics you want to use in your data app, selecting the columns you want to expose as Dimensions for filtering. Finally, query your Metrics using Propel's GraphQL API, which is always up and performant, and build in-product analytics into your app using the technology stack of your choice.