diff --git a/pkgs/servers/monitoring/prometheus/postfix-exporter.nix b/pkgs/servers/monitoring/prometheus/postfix-exporter.nix
index 506d334a921b..c66373e92982 100644
--- a/pkgs/servers/monitoring/prometheus/postfix-exporter.nix
+++ b/pkgs/servers/monitoring/prometheus/postfix-exporter.nix
@@ -1,4 +1,4 @@
-{ stdenv, buildGoPackage, fetchFromGitHub, makeWrapper, nixosTests
+{ stdenv, lib, buildGoPackage, fetchFromGitHub, makeWrapper, nixosTests
 , systemd, withSystemdSupport ? true }:
 
 with stdenv.lib;
@@ -44,7 +44,7 @@ buildGoPackage rec {
 
   postInstall = optionalString withSystemdSupport ''
     wrapProgram $out/bin/postfix_exporter \
-      --prefix LD_LIBRARY_PATH : "${systemd.lib}/lib"
+      --prefix LD_LIBRARY_PATH : "${lib.getLib systemd}/lib"
   '';
 
   passthru.tests = { inherit (nixosTests.prometheus-exporters) postfix; };