Not often. And depending of what is considered as base – only the core Postgres code, or contrib modules (shipped with it and supported by community). Extension

Not often. And depending of what is considered as base – only the core Postgres code, or contrib modules (shipped with it and supported by community). Extension/contrib -> core is a very rare event. For example, it happened with XML type and functions originated from contrib/xml2, and with contrib/tsearch2 which became FTS in core. But it's a very rare thing. And based on just these 2 examples, you should have -2 in the name:) As for external extension becoming a contrib module, it's not a frequent event as well: - Some "1000+ PostgreSQL EXTENSIONs" list https://gist.github.com/joelonsql/e5aa27f8cc9bd22b8999b7de8aee9d47 https://gist.github.com/joelonsql/e5aa27f8cc9bd22b8999b7de8a... - Current list of contrib modules – 58 modules https://gitlab.com/postgres/postgres/tree/master/contrib https://gitlab.com/postgres/postgres/tree/master/contrib - Same list 10 years ago, Postgres 9.2 – 53 modules https://gitlab.com/postgres/postgres/tree/REL9_2_STABLE/contrib https://gitlab.com/postgres/postgres/tree/REL9_2_STABLE/cont...