User Storage Provider and Codecentric's Helm Chart

Please be mindful that I am no expert in this area.

I want to build a User SPI to connect our Keycloak instance with an external data source. Specifically, we want to connect Keycloak to a mssql (Microsoft SQL Server) database that we own.

I watched some videos, one of which was @dasniko , and I feel like I don’t have enough experience to follow those videos. Where are the guides for creating the User SPI applications in Java for instance?

The Helm Chart we are using: https://github.com/codecentric/helm-charts/tree/master/charts/keycloakx

See Thread at Slack channel
Extensions are not related to any Helm Chart.
Extensions should IMHO copied into your custom image, then you can deploy this in any way you like.