diff --git a/.circleci/config.yml b/.circleci/config.yml
new file mode 100644
index 0000000..f5a436d
--- /dev/null
+++ b/.circleci/config.yml
@@ -0,0 +1,24 @@
+version: 2.1
+
+# Local validation: circleci config validate .circleci/config.yml
+# Mirrors build.config.yml for CircleCI CLI compatibility.
+
+orbs: {}
+
+jobs:
+  android-build:
+    docker:
+      - image: cimg/base:stable
+    steps:
+      - checkout
+      - run:
+          name: Run docker build runner
+          command: ./scripts/docker-build-runner.sh
+
+workflows:
+  androidcast:
+    jobs:
+      - android-build:
+          filters:
+            branches:
+              only: [next, master]
diff --git a/examples/crash_reporter/backend/nginx.fe-build-inline.snippet b/examples/crash_reporter/backend/nginx.fe-build-inline.snippet
new file mode 100644
index 0000000..1559ffb
--- /dev/null
+++ b/examples/crash_reporter/backend/nginx.fe-build-inline.snippet
@@ -0,0 +1,13 @@
+# Paste into Gentoo FE /etc/nginx/nginx.conf inside server { listen 443; server_name apps.f0xx.org; }
+# Place immediately AFTER the crashes location block (same style as hub + crashes).
+
+		location /app/androidcast_project/build/ {
+		 	proxy_pass https://artc0.intra.raptor.org/app/androidcast_project/build/;
+		}
+
+# Then REMOVE or comment out the build location in /etc/nginx/apps.conf (avoid duplicate/conflict).
+# Reload: nginx -t && rc-service nginx reload
+
+# Verify from FE:
+#   curl -sSI -H 'Host: apps.f0xx.org' http://127.0.0.1/app/androidcast_project/build/ | head -5
+# Expect 302 + x-powered-by: PHP (after BE fragment is fixed too).
diff --git a/examples/crash_reporter/backend/scripts/diagnose-build-proxy.sh b/examples/crash_reporter/backend/scripts/diagnose-build-proxy.sh
new file mode 100755
index 0000000..c403371
--- /dev/null
+++ b/examples/crash_reporter/backend/scripts/diagnose-build-proxy.sh
@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+# Run on Gentoo FE and Alpine BE to diagnose build proxy (paste output when asking for help).
+set -u
+echo "=== $(hostname) build proxy diagnostic ==="
+echo
+
+if [[ -f /etc/nginx/nginx.conf ]]; then
+  echo "--- FE: androidcast locations in nginx.conf ---"
+  grep -n 'androidcast_project' /etc/nginx/nginx.conf | head -20
+  echo
+fi
+if [[ -f /etc/nginx/apps.conf ]]; then
+  echo "--- FE: apps.conf ---"
+  cat /etc/nginx/apps.conf
+  echo
+fi
+if [[ -f /etc/nginx/conf.d/apps_builder.frag ]]; then
+  echo "--- BE: apps_builder.frag ---"
+  cat /etc/nginx/conf.d/apps_builder.frag
+  echo
+fi
+if [[ -f /etc/nginx/conf.d/apps.conf ]]; then
+  echo "--- BE: apps.conf listen 80 (first 25 lines) ---"
+  sed -n '1,25p' /etc/nginx/conf.d/apps.conf
+  echo
+fi
+
+echo "--- DNS artc0 ---"
+getent hosts artc0.intra.raptor.org 2>/dev/null || true
+
+echo "--- Local curls ---"
+for url in \
+  "http://127.0.0.1/app/androidcast_project/build/" \
+  "http://artc0.intra.raptor.org/app/androidcast_project/build/" \
+  "https://artc0.intra.raptor.org/app/androidcast_project/build/"; do
+  code=$(curl -sS -o /dev/null -w "%{http_code}" -H "Host: apps.f0xx.org" -k "$url" 2>/dev/null || echo "fail")
+  echo "$code  $url"
+done
+
+echo "--- PHP index exists? ---"
+ls -la /var/www/localhost/htdocs/apps/app/androidcast_project/android_cast/examples/build_console/backend/public/index.php 2>&1 || true