diff --git a/docs/changelog/7.x.x.txt b/docs/changelog/7.x.x.txt
index b86fb8d4b..0feefb60c 100644
--- a/docs/changelog/7.x.x.txt
+++ b/docs/changelog/7.x.x.txt
@@ -1,4 +1,5 @@
 7.5.21
+ - fixed: Custom library directories don't override WebGUI core modules
  - Changed update() so that it only updates fields passed in, and the defaults
    for assets are processed in addRevision() instead.
  - Changed update() so it can autodetect missing fields in asset tables and
diff --git a/sbin/preload.perl b/sbin/preload.perl
index f869658cd..9dcc9d6c5 100644
--- a/sbin/preload.perl
+++ b/sbin/preload.perl
@@ -2,7 +2,7 @@ use strict;
 
 my $webguiRoot = '/data/WebGUI';
 
-my @webguiLibs = ($webguiRoot."/lib");
+my @webguiLibs;
 
 # add custom lib directories to library search path
 for my $libDir (readLines($webguiRoot."/sbin/preload.custom")) {
@@ -12,6 +12,7 @@ for my $libDir (readLines($webguiRoot."/sbin/preload.custom")) {
     }
     push @webguiLibs, $libDir;
 }
+push @webguiLibs, $webguiRoot . "/lib";
 unshift @INC, @webguiLibs;
 
 #----------------------------------------