Standard Notes comprises of two main technologies that work together to ensure a private, secure experience. One is the core stack of Standard Notes client applications. On the other end is a simple framework called Standard File used for encrypting data locally and syncing it to the cloud.
When you sign up for a private sync account on Standard Notes, we use a Standard File system to host your data and generate your encryption keys locally.
If you're interested in using your own private server for use with Standard Notes, you would need to simply deploy a Standard File server.
If you'd like to self-host the actual Standard Notes web application, visit the web repo on GitHub.