diff --git a/pkgs/development/python-modules/scikitlearn/default.nix b/pkgs/development/python-modules/scikitlearn/default.nix
index 04ea254ee92..399bf56af0a 100644
--- a/pkgs/development/python-modules/scikitlearn/default.nix
+++ b/pkgs/development/python-modules/scikitlearn/default.nix
@@ -1,22 +1,23 @@
-{ stdenv, buildPythonPackage, fetchPypi
-, gfortran, glibcLocales
-, numpy, scipy, pytest, pillow
+{ stdenv, buildPythonPackage, fetchPypi, python
+, gfortran, glibcLocales, joblib, pythonOlder
+, numpy, scipy, pytest, pillow, cython
 }:
 
 buildPythonPackage rec {
   pname = "scikit-learn";
-  version = "0.20.3";
+  version = "0.21.2";
   # UnboundLocalError: local variable 'message' referenced before assignment
-  disabled = stdenv.isi686;  # https://github.com/scikit-learn/scikit-learn/issues/5534
+  disabled = stdenv.isi686 || (pythonOlder "3.5");  # https://github.com/scikit-learn/scikit-learn/issues/5534
 
   src = fetchPypi {
     inherit pname version;
-    sha256 = "c503802a81de18b8b4d40d069f5e363795ee44b1605f38bc104160ca3bfe2c41";
+    sha256 = "0aafc312a55ebf58073151b9308761a5fcfa45b7f7730cea4b1f066f824c72db";
   };
 
   buildInputs = [ pillow gfortran glibcLocales ];
-  propagatedBuildInputs = [ numpy scipy numpy.blas ];
+  propagatedBuildInputs = [ numpy scipy numpy.blas joblib ];
   checkInputs = [ pytest ];
+  nativeBuildInputs = [ cython ];
 
   LC_ALL="en_US.UTF-8";