diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 2cc690ff59c..7d9537854bf 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -395,6 +395,8 @@ let
   acoustidFingerprinter = callPackage
     ../tools/audio/acoustid-fingerprinter { };
 
+  actdiag = pythonPackages.actdiag;
+
   aefs = callPackage ../tools/filesystems/aefs { };
 
   aespipe = callPackage ../tools/security/aespipe { };
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index 5c6354d6e3a..6754537e72b 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -131,6 +131,31 @@ pythonPackages = modules // import ./python-packages-generated.nix {
 
   # packages defined here
 
+  actdiag = buildPythonPackage rec {
+    name = "actdiag-0.4.3";
+
+    src = fetchurl {
+      url = "https://pypi.python.org/packages/source/a/actdiag/${name}.tar.gz";
+      md5 = "428aaab849f04668fa12388b964a56ea";
+    };
+
+    buildInputs = [ pep8 nose unittest2 docutils ];
+
+    propagatedBuildInputs = [ blockdiag ];
+
+    # One test fails, because of missing simple.diag input file
+    doCheck = false;
+
+    meta = with stdenv.lib; {
+      description = "Generate activity-diagram image from spec-text file (similar to Graphviz)";
+      homepage = http://blockdiag.com/;
+      license = licenses.asl20;
+      platforms = platforms.linux;
+      maintainers = [ maintainers.bjornfor ];
+    };
+  };
+
+
   afew = buildPythonPackage rec {
     rev = "6bb3915636aaf86f046a017ffffd9a4ef395e199";
     name = "afew-1.0_${rev}";