diff --git a/pkgs/development/libraries/haskell/yesod/default.nix b/pkgs/development/libraries/haskell/yesod/default.nix
index 2ab9b568313..c8e719b90e8 100644
--- a/pkgs/development/libraries/haskell/yesod/default.nix
+++ b/pkgs/development/libraries/haskell/yesod/default.nix
@@ -7,8 +7,8 @@
 
 cabal.mkDerivation (self: {
   pname = "yesod";
-  version = "0.10.1.1";
-  sha256 = "1d64kx0jfk1d1r4k8r57y5wz84pjxs481qdnzgjfv279y467fki6";
+  version = "0.10.1.3";
+  sha256 = "01r9b88gsj7f1mn56nm5dyzj2s46l9pg9p7fjwkf0l8zdfmrbflw";
   isLibrary = true;
   isExecutable = true;
   buildDepends = [
diff --git a/pkgs/development/libraries/zlib/default.nix b/pkgs/development/libraries/zlib/default.nix
index 7517b2e498a..f3c1684fa3f 100644
--- a/pkgs/development/libraries/zlib/default.nix
+++ b/pkgs/development/libraries/zlib/default.nix
@@ -1,12 +1,14 @@
 { stdenv, fetchurl, static ? false }:
 
+let version = "1.2.6"; in
+
 stdenv.mkDerivation rec {
-  name = "zlib-1.2.6";
+  name = "zlib-${version}";
   
   src = fetchurl {
-    urls = 
-      [ "http://www.zlib.net/${name}.tar.gz"
-        "http://gentoo.netnitco.net/distfiles/${name}.tar.gz" 
+    urls =
+      [ "http://www.zlib.net/${name}.tar.gz"  # old versions vanish from here
+        "mirror://sourceforge/libpng/zlib/${version}/${name}.tar.gz"
       ];
     sha256 = "06x6m33ls1606ni7275q5z392csvh18dgs55kshfnvrfal45w8r1";
   };
diff --git a/pkgs/tools/networking/openresolv/default.nix b/pkgs/tools/networking/openresolv/default.nix
index b2831fd4d7b..3aa818db728 100644
--- a/pkgs/tools/networking/openresolv/default.nix
+++ b/pkgs/tools/networking/openresolv/default.nix
@@ -17,7 +17,7 @@ stdenv.mkDerivation rec {
       LIBEXECDIR=$out/libexec/resolvconf
       VARDIR=/var/run/resolvconf
       MANDIR=$out/share/man
-      RESTARTCMD="initctl restart \1"
+      RESTARTCMD="false \1"
       EOF
     '';
 
diff --git a/pkgs/tools/package-management/nix/unstable.nix b/pkgs/tools/package-management/nix/unstable.nix
index 7ad69e8353a..235f85dc51a 100644
--- a/pkgs/tools/package-management/nix/unstable.nix
+++ b/pkgs/tools/package-management/nix/unstable.nix
@@ -4,12 +4,12 @@
 , stateDir ? "/nix/var"
 }:
 
-stdenv.mkDerivation (rec {
-  name = "nix-1.0pre31851";
+stdenv.mkDerivation rec {
+  name = "nix-1.0pre2606_8afd28a";
 
   src = fetchurl {
-    url = "http://hydra.nixos.org/build/1937677/download/4/${name}.tar.bz2";
-    sha256 = "36f07b6b701da74f07d8c8cc43044306e570b6837555ad523701d86e5f567568";
+    url = "http://hydra.nixos.org/build/2183656/download/4/${name}.tar.bz2";
+    sha256 = "4f21d01563ab9e949e09997ddaa89066c40a13b27e028a6fdffc67b97dd90dcb";
   };
 
   buildNativeInputs = [ perl pkgconfig ];
@@ -46,11 +46,13 @@ stdenv.mkDerivation (rec {
 
   doCheck = true;
 
+  # Hack to get the check to succeed on Darwin.
+  phases = stdenv.lib.optionalString stdenv.isDarwin
+    "$prePhases unpackPhase patchPhase $preConfigurePhases configurePhase $preBuildPhases buildPhase $preInstallPhases installPhase checkPhase fixupPhase $preDistPhases distPhase $postPhases";
+
   meta = {
     description = "The Nix Deployment System";
     homepage = http://nixos.org/;
     license = "LGPLv2+";
   };
-} // stdenv.lib.optionalAttrs stdenv.isDarwin {
-      phases = "$prePhases unpackPhase patchPhase $preConfigurePhases configurePhase $preBuildPhases buildPhase $preInstallPhases installPhase checkPhase fixupPhase $preDistPhases distPhase $postPhases";
-})
+}