diff --git a/.gitignore b/.gitignore
index 67b4552c..2396051b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,5 @@
 /build/
 /docs/_build/
-/docs/source/
 /dist/
 /.eggs/
 /*.egg-info
diff --git a/readthedocs.yml b/readthedocs.yml
new file mode 100644
index 00000000..504c5270
--- /dev/null
+++ b/readthedocs.yml
@@ -0,0 +1,5 @@
+python:
+  setup_py_install: true
+  requirements_file: requirements.txt
+  extra_requirements:
+    - appengine-sdk
diff --git a/setup.py b/setup.py
index 857a968e..e4dc102b 100644
--- a/setup.py
+++ b/setup.py
@@ -50,5 +50,8 @@
           'mf2util',
           'urllib3>=1.14',
       ],
+      extras_require={
+          'appengine-sdk': ['appengine-sdk>=1.9.40.post0'],
+      },
       test_suite='oauth_dropins.webutil',
 )