diff --git a/.travis.yml b/.travis.yml
index 45869fc..1c635c9 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -21,8 +21,5 @@ stages:
 jobs:
   include:
     - stage: lint
-      install:
-        - pip install black pyflakes
       script:
-        - pyflakes webmention tests
-        - black --check webmention tests
+        - tox -e lint
diff --git a/setup.cfg b/setup.cfg
index 66c88e5..480804a 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -29,14 +29,14 @@ classifiers =
     Programming Language :: Python :: 3.7
 
 [options]
+package_dir = =src
 packages = find:
 install_requires =
     Django>=1.8.2
     requests>=2.7.0
 
 [options.packages.find]
-exclude =
-    tests*
+where = src
 
 [options.extras_require]
 test =
@@ -44,6 +44,9 @@ test =
     pytest
     pytest-cov
     pytest-django
+lint =
+    pyflakes
+    black
 
 [coverage:run]
 branch = True
@@ -75,8 +78,14 @@ envlist = {py35,py36,py37,py38}-django{1.11,2.1,2.2}
 [testenv]
 extras = test
 commands =
-    pytest
+    pytest {posargs}
 deps =
     django1.11: Django>=1.11,<2
     django2.1: Django>=2.1,<2.2
     django2.2: Django>=2.2,<2.3
+
+[testenv:lint]
+extras = lint
+commands =
+    pyflakes src/webmention tests
+    black --check src/webmention tests
diff --git a/webmention/__init__.py b/src/webmention/__init__.py
similarity index 100%
rename from webmention/__init__.py
rename to src/webmention/__init__.py
diff --git a/webmention/admin.py b/src/webmention/admin.py
similarity index 100%
rename from webmention/admin.py
rename to src/webmention/admin.py
diff --git a/webmention/checks.py b/src/webmention/checks.py
similarity index 100%
rename from webmention/checks.py
rename to src/webmention/checks.py
diff --git a/webmention/middleware.py b/src/webmention/middleware.py
similarity index 100%
rename from webmention/middleware.py
rename to src/webmention/middleware.py
diff --git a/webmention/migrations/0001_initial.py b/src/webmention/migrations/0001_initial.py
similarity index 100%
rename from webmention/migrations/0001_initial.py
rename to src/webmention/migrations/0001_initial.py
diff --git a/webmention/migrations/__init__.py b/src/webmention/migrations/__init__.py
similarity index 100%
rename from webmention/migrations/__init__.py
rename to src/webmention/migrations/__init__.py
diff --git a/webmention/models.py b/src/webmention/models.py
similarity index 100%
rename from webmention/models.py
rename to src/webmention/models.py
diff --git a/webmention/resolution.py b/src/webmention/resolution.py
similarity index 100%
rename from webmention/resolution.py
rename to src/webmention/resolution.py
diff --git a/webmention/urls.py b/src/webmention/urls.py
similarity index 100%
rename from webmention/urls.py
rename to src/webmention/urls.py
diff --git a/webmention/views.py b/src/webmention/views.py
similarity index 100%
rename from webmention/views.py
rename to src/webmention/views.py