Future plans for custom expectations types

[janina-schu]

Dear great expectations team,
could you share what your future plans are for custom expectations (i.e, enabling community members to implement their own type of expectations to evaluate data quality use cases that are not covered by the expectation gallery)? I noticed that there used to be a documentation for this in version 0.16 (e.g., https://docs.greatexpectations.io/docs/0.18/oss/guides/expectations/creating_custom_expectations/how_to_create_custom_multicolumn_map_expectations) and not in version 1 upwards.
Thank you in advance!
Best,
Janina