diff --git a/pkgs/tools/networking/isync/default.nix b/pkgs/tools/networking/isync/default.nix
index 581a45eaebb9..5bdbe17e4d10 100644
--- a/pkgs/tools/networking/isync/default.nix
+++ b/pkgs/tools/networking/isync/default.nix
@@ -1,4 +1,4 @@
-{ fetchurl, stdenv, openssl, pkgconfig, db, cyrus_sasl, perl }:
+{ fetchurl, stdenv, openssl, pkgconfig, db, zlib, cyrus_sasl, perl }:
 
 stdenv.mkDerivation rec {
   name = "isync-1.3.0";
@@ -9,7 +9,7 @@ stdenv.mkDerivation rec {
   };
 
   nativeBuildInputs = [ pkgconfig perl ];
-  buildInputs = [ openssl db cyrus_sasl ];
+  buildInputs = [ openssl db cyrus_sasl zlib ];
 
   meta = with stdenv.lib; {
     homepage = http://isync.sourceforge.net/;