HomeX3 GraphQL API for X3 Quick Start Guide 1. Set up the Basics Set up the Basics Less than 1 minute to read Before you start developing, we need to make sure you have the following ready to go. Sign up for SageID. You can sign up with your email address. Sign up for Sage App Registry. You can read our guide on Register your organization. Sign up for a free Postman account and download the Postman app.