diff --git a/pkgs/python-packages.nix b/pkgs/python-packages.nix
--- a/pkgs/python-packages.nix
+++ b/pkgs/python-packages.nix
@@ -354,13 +354,13 @@
     };
   };
   mercurial = super.buildPythonPackage {
-    name = "mercurial-4.2.3";
+    name = "mercurial-4.4";
     buildInputs = with self; [];
     doCheck = false;
     propagatedBuildInputs = with self; [];
     src = fetchurl {
-      url = "https://www.mercurial-scm.org/release/mercurial-4.2.3.tar.gz";
-      md5 = "a24a8fab7c2ad2c65e945b1b35d94e3b";
+      url = "https://pypi.python.org/packages/ad/a2/26cd147e44acdcaceada23e93ffec49e4f6adfc57db647f3d071db411961/mercurial-4.4.tar.gz";
+      md5 = "c1d9fad1b7ed7077b0d4ae82e71154db";
     };
     meta = {
       license = [ pkgs.lib.licenses.gpl1 pkgs.lib.licenses.gpl2Plus ];
diff --git a/requirements.txt b/requirements.txt
--- a/requirements.txt
+++ b/requirements.txt
@@ -8,7 +8,7 @@ dulwich==0.13.0
 hgsubversion==1.8.7
 hg-evolve==6.6.0
 infrae.cache==1.0.1
-mercurial==4.2.3
+mercurial==4.4.0
 msgpack-python==0.4.8
 pyramid-jinja2==2.5
 pyramid==1.9.1