diff --git a/pkgs/development/libraries/skalibs/default.nix b/pkgs/development/libraries/skalibs/default.nix
index aaa7b3a3d26..67c1c74e6cf 100644
--- a/pkgs/development/libraries/skalibs/default.nix
+++ b/pkgs/development/libraries/skalibs/default.nix
@@ -1,20 +1,23 @@
-{ stdenv, fetchurl }:
+{ stdenv, fetchgit }:
 
 let
 
-  version = "2.0.0.0";
+  version = "2.2.0.0";
 
 in stdenv.mkDerivation rec {
 
   name = "skalibs-${version}";
 
-  src = fetchurl {
-    url = "http://skarnet.org/software/skalibs/${name}.tar.gz";
-    sha256 = "0cz30wqg8fnkwjlacs4s3sjs3l34sa91xgci95fmb187zhiq693n";
+  src = fetchgit {
+    url = "git://git.skarnet.org/skalibs";
+    rev = "refs/tags/v${version}";
+    sha256 = "1ww45ygrws7h3p3p7y3blc5kzvvy5fmzb158ngfbdamf0pgc5vkn";
   };
 
   dontDisableStatic = true;
 
+  enableParallelBuilding = true;
+
   configureFlags = [
     "--enable-force-devr"       # assume /dev/random works
     "--libdir=\${prefix}/lib"
diff --git a/pkgs/servers/s6/default.nix b/pkgs/servers/s6/default.nix
index 32d219bf4aa..1452f82573e 100644
--- a/pkgs/servers/s6/default.nix
+++ b/pkgs/servers/s6/default.nix
@@ -1,20 +1,23 @@
-{ stdenv, execline, fetchurl, skalibs }:
+{ stdenv, execline, fetchgit, skalibs }:
 
 let
 
-  version = "2.0.0.0";
+  version = "2.0.1.0";
 
 in stdenv.mkDerivation rec {
 
   name = "s6-${version}";
 
-  src = fetchurl {
-    url = "http://www.skarnet.org/software/s6/${name}.tar.gz";
-    sha256 = "14x4l3xp152c9v34zs7nzxzacizfpp0k0lzwh40rxm0w5wz4x0ls";
+  src = fetchgit {
+    url = "git://git.skarnet.org/s6";
+    rev = "refs/tags/v${version}";
+    sha256 = "1x7za0b1a2i6xn06grpb5j361s9bl4524bp5mz3zcdg8s9nil50d";
   };
 
   dontDisableStatic = true;
 
+  enableParallelBuilding = true;
+
   configureFlags = [
     "--with-sysdeps=${skalibs}/lib/skalibs/sysdeps"
     "--with-include=${skalibs}/include"
diff --git a/pkgs/tools/misc/execline/default.nix b/pkgs/tools/misc/execline/default.nix
index 96126233458..320115b4f2d 100644
--- a/pkgs/tools/misc/execline/default.nix
+++ b/pkgs/tools/misc/execline/default.nix
@@ -1,20 +1,23 @@
-{ stdenv, fetchurl, skalibs }:
+{ stdenv, fetchgit, skalibs }:
 
 let
 
-  version = "2.0.0.0";
+  version = "2.0.1.1";
 
 in stdenv.mkDerivation rec {
 
   name = "execline-${version}";
 
-  src = fetchurl {
-    url = "http://skarnet.org/software/execline/${name}.tar.gz";
-    sha256 = "1g5v6icxsf7p2ccj9iq85iikkm12xph65ri86ydakihv6al3jw71";
+  src = fetchgit {
+    url = "git://git.skarnet.org/execline";
+    rev = "refs/tags/v${version}";
+    sha256 = "06fn4fb8hp68pffgfc55l5raph3bk9v0gngbgxfyzkmwbb1gxhll";
   };
 
   dontDisableStatic = true;
 
+  enableParallelBuilding = true;
+
   configureFlags = [
     "--libdir=\${prefix}/lib"
     "--includedir=\${prefix}/include"
diff --git a/pkgs/tools/networking/s6-dns/default.nix b/pkgs/tools/networking/s6-dns/default.nix
index 4dae1a1c8c3..2339ac5ff05 100644
--- a/pkgs/tools/networking/s6-dns/default.nix
+++ b/pkgs/tools/networking/s6-dns/default.nix
@@ -1,20 +1,23 @@
-{ stdenv, fetchurl, skalibs }:
+{ stdenv, fetchgit, skalibs }:
 
 let
 
-  version = "2.0.0.0";
+  version = "2.0.0.2";
 
 in stdenv.mkDerivation rec {
 
   name = "s6-dns-${version}";
 
-  src = fetchurl {
-    url = "http://www.skarnet.org/software/s6-dns/${name}.tar.gz";
-    sha256 = "07k6rzgsgcxr0bq209as79sjn2nrcjj9mlmk9vvy1hvsag0xnkcq";
+  src = fetchgit {
+    url = "git://git.skarnet.org/s6-dns";
+    rev = "refs/tags/v${version}";
+    sha256 = "0y76gvgvg2y3hhr3pk2nkki1idjj6sxxcnvd29yd79v0419p2dl3";
   };
 
   dontDisableStatic = true;
 
+  enableParallelBuilding = true;
+
   configureFlags = [
     "--includedir=\${prefix}/include"
     "--libdir=\${prefix}/lib"
diff --git a/pkgs/tools/networking/s6-networking/default.nix b/pkgs/tools/networking/s6-networking/default.nix
index 09d9e722245..e8857e35e67 100644
--- a/pkgs/tools/networking/s6-networking/default.nix
+++ b/pkgs/tools/networking/s6-networking/default.nix
@@ -1,30 +1,36 @@
-{ stdenv, execline, fetchurl, s6Dns, skalibs }:
+{ stdenv, execline, fetchgit, s6, s6Dns, skalibs }:
 
 let
 
-  version = "2.0.0.0";
+  version = "2.0.1.0";
 
 in stdenv.mkDerivation rec {
 
   name = "s6-networking-${version}";
 
-  src = fetchurl {
-    url = "http://www.skarnet.org/software/s6-networking/${name}.tar.gz";
-    sha256 = "0k2i0g5lsvh1gz90ixwdip1pngj9vd45d4fpmdg075vd8zhh7j37";
+  src = fetchgit {
+    url = "git://git.skarnet.org/s6-networking";
+    rev = "refs/tags/v${version}";
+    sha256 = "1q094x8x99cy0kkq74kfw1rd9kmp6ynpz9ahx0lviz05n9paq7ya";
   };
 
   dontDisableStatic = true;
 
+  enableParallelBuilding = true;
+
   configureFlags = [
     "--with-sysdeps=${skalibs}/lib/skalibs/sysdeps"
     "--with-include=${skalibs}/include"
     "--with-include=${execline}/include"
+    "--with-include=${s6}/include"
     "--with-include=${s6Dns}/include"
     "--with-lib=${skalibs}/lib"
     "--with-lib=${execline}/lib"
+    "--with-lib=${s6}/lib"
     "--with-lib=${s6Dns}/lib"
     "--with-dynlib=${skalibs}/lib"
     "--with-dynlib=${execline}/lib"
+    "--with-dynlib=${s6}/lib"
     "--with-dynlib=${s6Dns}/lib"
   ];