Databricks is first and in development. Snowflake and Microsoft Fabric are planned after it; their connectors are tested only on simulated services. PostgreSQL, MySQL and SQLite are in development as sources, and SQL Server is planned as one: Emolysis reads from sources and never deploys to them.
DuckDB is the local engine on your machine for development and golden tests; it is not a production target.
Each target platform gets the same set of ten pipeline shapes, with templates written for that platform's dialect, table format and deployment unit. The platforms page lists what each profile captures and what each connect flow looks like. No date is set for any platform after Databricks.