New comment by Chocimier on void-packages repository https://github.com/void-linux/void-packages/pull/18121#issuecomment-600309942 Comment: The goal is to allow upgrade database from 9.6 to 12 with pg_upgrade. This requires to simultanoulsy install both versions. Shared library seems to be reusable. Package is installed into /opt because pg_upgrade needs separate bindir for old and new version. Modifying configure_args from build-style allows to consistenly set all installation paths. System account and its parameters are same as in postgresql[9.6]. Manpages are suffixed with -12 and moved do default mandir. Tested upgrading databases: one with tcl stored procedure and trivial postgis table and repology db using out-of-tree compiled extension.