--- a/taskcluster/taskgraph/task/docker_image.py
+++ b/taskcluster/taskgraph/task/docker_image.py
@@ -73,18 +73,23 @@ class DockerImageTask(base.Task):
             image_artifact_path = \
                 "public/decision_task/image_contexts/{}/context.tar.gz".format(image_name)
             if os.environ.get('TASK_ID'):
                 destination = os.path.join(
                     os.environ['HOME'],
                     "artifacts/decision_task/image_contexts/{}/context.tar.gz".format(image_name))
                 image_parameters['context_url'] = ARTIFACT_URL.format(
                     os.environ['TASK_ID'], image_artifact_path)
-                context_hash = cls.create_context_tar(context_path, destination,
-                                                      image_name)
+
+                destination = os.path.abspath(destination)
+                if not os.path.exists(os.path.dirname(destination)):
+                    os.makedirs(os.path.dirname(destination))
+
+                context_hash = create_context_tar(GECKO, context_path,
+                                                  destination, image_name)
             else:
                 # skip context generation since this isn't a decision task
                 # TODO: generate context tarballs using subdirectory clones in
                 # the image-building task so we don't have to worry about this.
                 image_parameters['context_url'] = 'file:///tmp/' + image_artifact_path
                 context_hash = generate_context_hash(GECKO, context_path, image_name)
 
             image_parameters['context_hash'] = context_hash
@@ -129,28 +134,16 @@ class DockerImageTask(base.Task):
                 # HEAD success on the artifact is enough
                 return True, existing_task['taskId']
             except urllib2.HTTPError:
                 pass
 
         return False, None
 
     @classmethod
-    def create_context_tar(cls, context_dir, destination, image_name):
-        """Creates a tar file of a particular context directory.
-
-        Returns the SHA-256 hex digest of the created file.
-        """
-        destination = os.path.abspath(destination)
-        if not os.path.exists(os.path.dirname(destination)):
-            os.makedirs(os.path.dirname(destination))
-
-        return create_context_tar(GECKO, context_dir, destination, image_name)
-
-    @classmethod
     def from_json(cls, task_dict):
         # Generating index_paths for optimization
         routes = task_dict['task']['routes']
         index_paths = []
         for route in routes:
             index_path_regex = re.compile(INDEX_REGEX)
             result = index_path_regex.search(route)
             if result is None:

--- a/taskcluster/taskgraph/test/test_task_docker_image.py
+++ b/taskcluster/taskgraph/test/test_task_docker_image.py
@@ -1,16 +1,15 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 from __future__ import absolute_import, print_function, unicode_literals
 
 import unittest
-import tempfile
 import os
 
 from ..task import docker_image
 from mozunit import main
 
 
 KIND_PATH = os.path.join(docker_image.GECKO, 'taskcluster', 'ci', 'docker-image')
 
@@ -26,17 +25,11 @@ class TestDockerImageKind(unittest.TestC
             index_paths=[])
 
     def test_get_task_dependencies(self):
         # this one's easy!
         self.assertEqual(self.task.get_dependencies(None), [])
 
     # TODO: optimize_task
 
-    def test_create_context_tar(self):
-        image_dir = os.path.join(docker_image.GECKO, 'testing', 'docker', 'image_builder')
-        tarball = tempfile.mkstemp()[1]
-        self.task.create_context_tar(image_dir, tarball, 'image_builder')
-        self.failUnless(os.path.exists(tarball))
-        os.unlink(tarball)
 
 if __name__ == '__main__':
     main()