The SQL Server team has an announcement:
Previously, we announced a Java extension. Today, we are sharing that we are open sourcing the R and Python language extensions for SQL Server for both Windows and Linux on GitHub.
These extensions are the latest examples using an evolved programming language extensibility architecture which allows integration with a new type of language extension. This new architecture gives customers the freedom to bring their own runtime and execute programs using that runtime in SQL Server, while leveraging the existing security and governance that the SQL Server programming language extensibility architecture provides.
Very interesting.