Show mobile build slug separately from the church seen in analytics

README.md

@@ -208,7 +208,10 @@ The legacy `GET /airflow-fleet-health` Better Stack monitor endpoint has been re
 `GET /apps` reads the Segment BigQuery export and shows the highest observed Apollos
 version signal per church/app/platform. It uses the analytics metadata sent by the mobile and TV
 apps, including the exported `apollos_version`, `app_version`, `app_update_id`, `bundle_id`,
-`application_name`, `church`, `apollos_platform`, `source_revision`, and `source_version` fields.
+`application_name`, `church`, `build_church`, `apollos_platform`, `source_revision`, and
+`source_version` fields. For mobile apps, `build_church` is the configured deployment slug while
+`church` is a church selected inside the app (which can differ in Preview). Older mobile events
+without `build_church` show "Unknown build slug" rather than mislabeling the selected church.
 The public US Apple lookup is shown separately for iOS bundle IDs, with the fetch time. It can
 lag App Store Connect and must not be treated as an authoritative published release. The seen
 build is the version reported by the selected installation in Segment, not the latest shipped

app_versions.py

@@ -39,6 +39,7 @@
 
 FIELD_CANDIDATES = {
     "church": ("church", "group_id", "groupId"),
+    "build_church": ("build_church", "buildChurch"),
     "apollos_platform": ("apollos_platform", "apollosPlatform", "apollosplatform"),
     "apollos_version": ("apollos_version", "apollosVersion"),
     "app_version": ("app_version", "appVersion"),
@@ -262,8 +263,6 @@ def _build_app_versions_query(
               CURRENT_TIMESTAMP(),
               INTERVAL @lookback_days DAY
             )
-              AND `{version_column}` IS NOT NULL
-              AND CAST(`{version_column}` AS STRING) != ''
             """
         )
 
@@ -278,6 +277,7 @@ def _build_app_versions_query(
           SELECT
             seen_at,
             COALESCE(NULLIF(church, ''), 'Unknown church') AS church,
+            NULLIF(build_church, '') AS build_church,
             COALESCE(
               NULLIF(apollos_platform, ''),
               IF(source_dataset = 'apollos_roku', 'roku', NULL),
@@ -304,7 +304,7 @@ def _build_app_versions_query(
             source_table,
             version_source
           FROM version_events
-          WHERE apollos_version IS NOT NULL AND apollos_version != ''
+          WHERE apollos_version IS NOT NULL OR build_church IS NOT NULL
         ),
         filtered_events AS (
           SELECT *
@@ -335,17 +335,20 @@ def _build_app_versions_query(
           SELECT
             app_identity_key,
             ARRAY_AGG(
-              church
+              IF(apollos_version IS NOT NULL, church, NULL) IGNORE NULLS
               ORDER BY IF(church = 'Unknown church', 1, 0), church
               LIMIT 1
-            )[OFFSET(0)] AS church
+            )[SAFE_OFFSET(0)] AS church,
+            ARRAY_AGG(build_church IGNORE NULLS ORDER BY seen_at DESC LIMIT 1)
+              [SAFE_OFFSET(0)] AS build_church
           FROM app_identity_events
           GROUP BY app_identity_key
         ),
         version_observations AS (
           SELECT
             events.app_identity_key,
             display_churches.church,
+            display_churches.build_church,
             events.apollos_platform,
             events.application_name,
             events.bundle_id,
@@ -362,9 +365,11 @@ def _build_app_versions_query(
           FROM app_identity_events events
           JOIN display_churches
             USING (app_identity_key)
+          WHERE events.apollos_version IS NOT NULL
           GROUP BY
             events.app_identity_key,
             display_churches.church,
+            display_churches.build_church,
             events.apollos_platform,
             events.application_name,
             events.bundle_id,
@@ -380,6 +385,7 @@ def _build_app_versions_query(
         )
         SELECT
           observation.church,
+          observation.build_church,
           observation.apollos_platform,
           observation.application_name,
           observation.bundle_id,

templates/app_versions.html

@@ -159,7 +159,7 @@ <h2>App data is unavailable</h2>
           <table class="version-table">
             <thead>
               <tr>
-                <th>Church</th>
+                <th>{{ "Build slug / church seen" if tab.key in ("ios", "android") else "Church seen" }}</th>
                 <th>App</th>
                 <th>Seen build</th>
                 {% if tab.key == "ios" %}<th>Apple lookup (US)</th>{% endif %}
@@ -171,7 +171,12 @@ <h2>App data is unavailable</h2>
               {% for row in tab.rows %}
                 <tr>
                   <td>
-                    <strong>{{ row.church }}</strong>
+                    {% if tab.key in ("ios", "android") %}
+                      <strong>{{ row.build_church or "Unknown build slug" }}</strong><br />
+                      <span class="version-muted">Church seen: {{ row.church }}</span>
+                    {% else %}
+                      <strong>{{ row.church }}</strong>
+                    {% endif %}
                   </td>
                   <td>{{ row.application_name }}<br /><span class="version-muted">{{ row.bundle_id }}</span></td>
                   <td>

tests/test_app_versions.py

@@ -612,6 +612,7 @@ def test_builds_query_from_discovered_segment_columns(self):
             ("apollos", "tracks"): {
                 "timestamp": "timestamp",
                 "church": "church",
+                "buildchurch": "buildChurch",
                 "apollos_version": "apollos_version",
                 "app_version": "app_version",
                 "source_revision": "source_revision",
@@ -660,6 +661,14 @@ def test_builds_query_from_discovered_segment_columns(self):
         )
         self.assertIn("CAST(NULL AS STRING) AS source_revision", query)
         self.assertIn("NULLIF(CAST(`groupId` AS STRING), '') AS church", query)
+        self.assertIn("NULLIF(CAST(`buildChurch` AS STRING), '') AS build_church", query)
+        self.assertIn("[SAFE_OFFSET(0)] AS church", query)
+        self.assertIn("[SAFE_OFFSET(0)] AS build_church", query)
+        self.assertIn("observation.build_church", query)
+        self.assertNotIn("AND `apollos_version` IS NOT NULL", query)
+        self.assertIn("WHERE apollos_version IS NOT NULL OR build_church IS NOT NULL", query)
+        self.assertIn("IF(apollos_version IS NOT NULL, church, NULL) IGNORE NULLS", query)
+        self.assertIn("WHERE events.apollos_version IS NOT NULL", query)
         self.assertIn("'analytics_library' AS version_source", query)
         self.assertIn("TIMESTAMP_SUB(", query)
         self.assertIn("INTERVAL @lookback_days DAY", query)
@@ -797,6 +806,8 @@ def test_apps_route_renders_platform_tabs(self):
         self.assertIn('data-version-tab="android"', body)
         self.assertIn('id="version-panel-ios"', body)
         self.assertIn("One Church", body)
+        self.assertIn("Unknown build slug", body)
+        self.assertIn("Church seen: one-church", body)
         self.assertIn("<th>Seen build</th>", body)
         self.assertIn("<th>Apple lookup (US)</th>", body)
         self.assertIn("<th>Expo Runtime</th>", body)
@@ -810,6 +821,7 @@ def test_apps_route_renders_platform_tabs(self):
     def test_preview_shows_church_slug_and_distinguishes_seen_from_apple_lookup(self):
         row = {
             "church": "apollos_demo",
+            "build_church": "apollos_preview",
             "bundle_id": "com.differential.apollospreview",
             "application_name": "Apollos Preview",
             "app_version": "1.0.0",
@@ -838,7 +850,9 @@ def test_preview_shows_church_slug_and_distinguishes_seen_from_apple_lookup(self
         }
         with patch.object(app_module, "get_app_versions_context", return_value=context):
             body = self.client.get("/apps").get_data(as_text=True)
-        self.assertIn("<strong>apollos_demo</strong>", body)
+        self.assertIn("<strong>apollos_preview</strong>", body)
+        self.assertIn("Church seen: apollos_demo", body)
+        self.assertNotIn("<strong>apollos_demo</strong>", body)
         self.assertIn("Apollos Preview", body)
         self.assertIn("Last seen unknown", body)
         self.assertIn("Checked 2026-09-25 08:45 PM EDT", body)