diff --git a/scripts/phabtalk/.gitignore b/scripts/phabtalk/.gitignore
index f5e96db..2491be3 100644
--- a/scripts/phabtalk/.gitignore
+++ b/scripts/phabtalk/.gitignore
@@ -1 +1,2 @@
-venv
\ No newline at end of file
+venv
+test-data/
\ No newline at end of file
diff --git a/scripts/phabtalk/phabtalk.py b/scripts/phabtalk/phabtalk.py
index cf83f38..c1f8cc8 100755
--- a/scripts/phabtalk/phabtalk.py
+++ b/scripts/phabtalk/phabtalk.py
@@ -1,18 +1,121 @@
 #!/usr/bin/env python3
-from phabricator import Phabricator
+# Copyright 2019 Google LLC
+#
+# Licensed under the the Apache License v2.0 with LLVM Exceptions (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://llvm.org/LICENSE.txt
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""Upload build results to Phabricator.
 
+As I did not like the Jenkins plugin, we're using this script to upload the 
+build status, a summary and the test reults to Phabricator."""
+
+import argparse
+import os
+from typing import Optional
+from phabricator import Phabricator
+from lxml import etree
 
 class PhabTalk:
+    """Talk to Phabricator to upload build results."""
 
-    def __init__(self):
-        self._phab = Phabricator()
+    def __init__(self, token: Optional[str]):
+        self._phab = Phabricator(token=token)
+        self._phab.update_interfaces()
 
-    def get_revision_id
+    def get_revision_id(self, diff: str):
+        """Get the revision ID for a diff from Phabricator."""
+        result = self._phab.differential.querydiffs(ids=[diff])
+        return 'D' + result[diff]['revisionID']
 
-def main(phid: str, diff: str):
-    result = phab.differential.querydiffs(ids=[diff])
-    return 'D'+result[diff]['revisionID'])
+    def comment_on_diff(self, diff: str, text: str):
+        """Add a comment to a differential based on the diff_id"""
+        self.comment_on_revision(self.get_revision_id(diff), text)
 
+    def comment_on_revision(self, revision: str, text: str):
+        """Add comment on a differential based on the revision id."""
+
+        transactions = [{
+            'type' : 'comment',
+            'value' : text
+        }]
+
+        # API details at
+        # https://secure.phabricator.com/conduit/method/differential.revision.edit/
+        self._phab.differential.revision.edit(objectIdentifier=revision, transactions=transactions)
+
+    def comment_on_diff_from_file(self, diff: str, text_file_path: str):
+        """Comment on a diff, read text from file."""
+        if text_file_path is None:
+            return
+        if not os.path.exists(text_file_path):
+            raise FileNotFoundError('Could not find file with comments: {}'.format(text_file_path))
+        
+        with open(text_file_path) as input_file:
+            text = input_file.read()
+        self.comment_on_diff(diff, text)
+
+    def report_test_results(self, phid: str, build_result_file: str):
+        """Report failed tests to phabricator.
+
+        Only reporting failed tests as the full test suite is too large to upload.
+        """
+        if build_result_file is None:
+            return
+        if not os.path.exists(build_result_file):
+            raise FileNotFoundError('Could not find file with build results: {}'.format(build_result_file))
+        
+        root_node = etree.parse(build_result_file)
+        unit_test_results = []
+        build_result_type = 'pass'
+        for test_case in root_node.xpath('//testcase'):
+            test_result = self._test_case_status(test_case)
+            if test_result == 'fail':
+                failure = test_case.find('failure')
+                test_result = {
+                    'name' : test_case.attrib['name'],
+                    'namespace' : test_case.attrib['classname'],
+                    'result' : test_result,
+                    'duration' : float(test_case.attrib['time']),
+                    'details' : failure.text
+                }
+                build_result_type = 'fail'
+                unit_test_results.append(test_result)
+
+        # API details at
+        # https://secure.phabricator.com/conduit/method/harbormaster.sendmessage/  
+        self._phab.harbormaster.sendmessage(buildTargetPHID=phid, type=build_result_type, 
+            unit=unit_test_results)
+
+    @staticmethod
+    def _test_case_status(test_case) -> str:
+        """Get the status of a test case based on an etree node."""
+        if test_case.find('failure') is not None:
+            return 'fail'
+        if test_case.find('skipped') is not None:
+            return 'skip'
+        return 'pass'
+
+def main():
+    parser = argparse.ArgumentParser(description='Write build status back to Phabricator.')
+    parser.add_argument('ph_id', type=str)
+    parser.add_argument('diff_id', type=str)   
+    parser.add_argument('--comment-file', type=str, dest='comment_file', default=None)
+    parser.add_argument('--test-result-file', type=str, dest='test_result_file',
+        default=os.path.join(os.path.curdir,'test-results.xml'))
+    parser.add_argument('--conduit-token', type=str, dest='conduit_token', default=None)
+    args = parser.parse_args()    
+
+    p = PhabTalk(args.conduit_token)
+    p.comment_on_diff_from_file(args.diff_id, args.comment_file)
+    p.report_test_results(args.ph_id, args.test_result_file)
 
 if __name__ == '__main__':
-    main('PHID-HMBT-vitgimipuq4ntrmacw67','223623')
\ No newline at end of file
+    main()
\ No newline at end of file
diff --git a/scripts/phabtalk/requirements.txt b/scripts/phabtalk/requirements.txt
index dc91ba8..1807179 100644
--- a/scripts/phabtalk/requirements.txt
+++ b/scripts/phabtalk/requirements.txt
@@ -1 +1,2 @@
-phabricator==0.7.0
\ No newline at end of file
+phabricator==0.7.0
+lxml==4.4.1
\ No newline at end of file