diff --git a/src/uk_bus_stops/templates/about.html b/src/uk_bus_stops/templates/about.html
index 3582235..095b952 100644
--- a/src/uk_bus_stops/templates/about.html
+++ b/src/uk_bus_stops/templates/about.html
@@ -107,6 +107,12 @@
         own policies and operational logs.
       </p>
 
+      <h2 id="source">Source code</h2>
+      <p>
+        The source code for this tool is available at
+        <a href="https://git.4angle.com/edward/openstreetmap-tools">git.4angle.com/edward/openstreetmap-tools</a>.
+      </p>
+
       <h2 id="api">JSON endpoints</h2>
       <p>The interface uses these endpoints. Errors have the form <code>{"error": "code", "message": "text"}</code>.</p>
       <div class="table-responsive">
diff --git a/tests/test_uk_bus_stops.py b/tests/test_uk_bus_stops.py
index db765c2..3a09ffe 100644
--- a/tests/test_uk_bus_stops.py
+++ b/tests/test_uk_bus_stops.py
@@ -267,4 +267,5 @@ def test_about_documents_urls_and_services(client: Any) -> None:
     assert b"?node=485403178" in response.data
     assert b"?lat=51.4545&amp;lon=-2.5879" in response.data
     assert b"overpass.atownsend.org.uk" in response.data
+    assert b"https://git.4angle.com/edward/openstreetmap-tools" in response.data
     assert b"JSON endpoints" in response.data