fix:

This fix ensures that the control files reference $libdir/$ext-$MIN_MAJ_VERSION (e.g., $libdir/postgis-3.3) which matches the actual library names built with the
  --with-library-minor-version flag. This allows:

  1. Multiple PostGIS versions to coexist (3.3.2 and 3.3.7 both use postgis-3.3.so)
  2. Extensions to properly find their libraries during upgrades
  3. The multi-version functionality to work correctly

Author: samrose

nix/ext/postgis.nix

@@ -114,7 +114,7 @@ let
         # move control files
         for ext in ${lib.concatStringsSep " " (cExtensions ++ sqlExtensions)}; do
           sed -e "/^default_version =/d" \
-              -e "s|^module_pathname = .*|module_pathname = '\$libdir/$ext'|" \
+              -e "s|^module_pathname = .*|module_pathname = '\$libdir/$ext-$MIN_MAJ_VERSION'|" \
             $out/share/postgresql/extension/$ext.control > $out/share/postgresql/extension/$ext--$MIN_MAJ_VERSION.control
           rm $out/share/postgresql/extension/$ext.control
           ln -s $out/share/postgresql/extension/$ext--${version}.sql $out/share/postgresql/extension/$ext--$MIN_MAJ_VERSION.sql