diff --git a/pkgs/development/python-modules/pyfxa/default.nix b/pkgs/development/python-modules/pyfxa/default.nix
index be6502893a3..4bde8e9997a 100644
--- a/pkgs/development/python-modules/pyfxa/default.nix
+++ b/pkgs/development/python-modules/pyfxa/default.nix
@@ -1,6 +1,6 @@
 { lib, buildPythonPackage, fetchPypi
 , requests, cryptography, pybrowserid, hawkauthlib, six
-, grequests, mock, responses, unittest2 }:
+, grequests, mock, responses, pytest }:
 
 buildPythonPackage rec {
   pname = "PyFxA";
@@ -21,9 +21,13 @@ buildPythonPackage rec {
   ];
 
   checkInputs = [
-    grequests mock responses unittest2
+    grequests mock responses pytest
   ];
 
+  checkPhase = ''
+    pytest
+  '';
+
   meta = with lib; {
     description = "Firefox Accounts client library for Python";
     homepage = https://github.com/mozilla/PyFxA;