diff --git a/doc/leader_follower.md b/doc/leader_follower.md
index 9319640..632e805 100644
--- a/doc/leader_follower.md
+++ b/doc/leader_follower.md
@@ -51,6 +51,77 @@ These leader-side actions enqueue async snapshot push:
 
 Queue retries with backoff until follower accepts snapshot.
 
+## Local Manual Testing
+
+Backend now has local manual setup target:
+
+```bash
+inv docker-blackbox-follow-manual-up
+```
+
+This starts:
+
+- leader production image on `http://127.0.0.1:3002`
+- follower production image on `http://127.0.0.1:3003`
+- separate leader and follower Postgres containers
+- bootstrapped owner users on both backends
+
+Teardown:
+
+```bash
+inv docker-blackbox-follow-down
+```
+
+### Local topology
+
+Compose setup now separates DB traffic:
+
+- `source-postgres` only on `source-db` internal network
+- `follower-postgres` only on `follower-db` internal network
+- both apps share only `sync` network
+
+This gives:
+
+- separate production app containers
+- separate production DB containers
+- DB isolation between leader and follower
+
+Important limit:
+
+- Docker Compose does **not** enforce true one-way HTTP reachability here
+- local setup still allows follower container to reach leader container over shared `sync` network
+- real production trust model still comes from backend design:
+  - leader pushes
+  - follower never pulls
+  - follower has no code path that contacts leader
+
+So local setup is good for frontend/manual testing of behavior, not strict network-policy simulation.
+
+### Manual frontend testing flow
+
+1. Run `inv docker-blackbox-follow-manual-up`
+2. Open leader backend at `http://127.0.0.1:3002`
+3. Open follower backend at `http://127.0.0.1:3003`
+4. Log in with:
+   - email: `e2e@example.com`
+   - password: `password123`
+5. On follower backend, create empty read-only follower tournament
+6. On leader backend, create normal tournament
+7. On leader tournament, set:
+   - `sync_target_url` to follower `PATCH /tournaments/:id/sync_state`
+   - `sync_auth_token` to same shared token used on follower
+8. Point local frontend leader instance to `http://127.0.0.1:3002`
+9. Point local frontend follower/remote instance to `http://127.0.0.1:3003`
+10. Progress tournament on leader, verify follower mirrors state and stays read only
+
+Frontend team can use this setup to build:
+
+- owner sync configuration UI
+- follower read-only UX
+- status display for `sync_last_pushed_at`
+- status display for `sync_last_push_error`
+- takeover flow by disabling `read_only_mode`
+
 ## Takeover
 
 If remote must become writable after sync phase:
diff --git a/docker-compose.blackbox-follow.yml b/docker-compose.blackbox-follow.yml
index debad6a..525d8c6 100644
--- a/docker-compose.blackbox-follow.yml
+++ b/docker-compose.blackbox-follow.yml
@@ -12,6 +12,8 @@ services:
       retries: 20
     volumes:
       - turniere-blackbox-follow-source-postgres:/var/lib/postgresql/data
+    networks:
+      - source-db
 
   follower-postgres:
     image: ${TURNIERE_BLACKBOX_POSTGRES_IMAGE:-postgres:16}
@@ -26,6 +28,8 @@ services:
       retries: 20
     volumes:
       - turniere-blackbox-follow-follower-postgres:/var/lib/postgresql/data
+    networks:
+      - follower-db
 
   source-app:
     image: ${TURNIERE_BLACKBOX_APP_IMAGE:-registry.gitlab.com/turniere/turniere-backend/production/commits:local}
@@ -44,6 +48,9 @@ services:
       RAILS_SERVE_STATIC_FILES: "1"
     ports:
       - "${TURNIERE_BLACKBOX_SOURCE_HOST_PORT:-3002}:3000"
+    networks:
+      - source-db
+      - sync
 
   follower-app:
     image: ${TURNIERE_BLACKBOX_APP_IMAGE:-registry.gitlab.com/turniere/turniere-backend/production/commits:local}
@@ -62,6 +69,9 @@ services:
       RAILS_SERVE_STATIC_FILES: "1"
     ports:
       - "${TURNIERE_BLACKBOX_FOLLOWER_HOST_PORT:-3003}:3000"
+    networks:
+      - follower-db
+      - sync
 
   e2e:
     image: ${TURNIERE_BLACKBOX_RUNNER_IMAGE:-registry.gitlab.com/turniere/turniere-backend/test/commits:local}
@@ -82,7 +92,16 @@ services:
       TURNIERE_E2E_ALT_EMAIL: ${TURNIERE_E2E_ALT_EMAIL:-e2e-alt@example.com}
       TURNIERE_E2E_ALT_PASSWORD: ${TURNIERE_E2E_ALT_PASSWORD:-password123}
       TURNIERE_E2E_ALT_USERNAME: ${TURNIERE_E2E_ALT_USERNAME:-e2e-alt-user}
+    networks:
+      - sync
 
 volumes:
   turniere-blackbox-follow-source-postgres:
   turniere-blackbox-follow-follower-postgres:
+
+networks:
+  source-db:
+    internal: true
+  follower-db:
+    internal: true
+  sync:
diff --git a/tasks.py b/tasks.py
index 206f382..ed68ca1 100644
--- a/tasks.py
+++ b/tasks.py
@@ -994,6 +994,55 @@ def docker_blackbox_follow_up(
     print("Follower production apps ready for blackbox E2E.")
 
 
+@task(name="docker-blackbox-follow-manual-up")
+def docker_blackbox_follow_manual_up(
+    c,
+    source_host_port=BLACKBOX_SOURCE_HOST_PORT,
+    follower_host_port=BLACKBOX_FOLLOWER_HOST_PORT,
+    app_image=PRODUCTION_TAG,
+    runner_image=TEST_TAG,
+    postgres_image=BLACKBOX_POSTGRES_IMAGE,
+    build=True,
+):
+    """Boot local leader/follower production setup for manual testing and print next steps."""
+    docker_blackbox_follow_up(
+        c,
+        source_host_port=source_host_port,
+        follower_host_port=follower_host_port,
+        app_image=app_image,
+        runner_image=runner_image,
+        postgres_image=postgres_image,
+        build=build,
+    )
+
+    source_env = _production_env_for("source-postgres", BLACKBOX_SOURCE_DB_NAME)
+    follower_env = _production_env_for("follower-postgres", BLACKBOX_FOLLOWER_DB_NAME)
+
+    _print_header("Running source production database migrations")
+    c.run("bundle exec rails db:migrate", env=source_env, pty=True)
+
+    _print_header("Running follower production database migrations")
+    c.run("bundle exec rails db:migrate", env=follower_env, pty=True)
+
+    _print_header("Bootstrapping confirmed E2E users on source and follower")
+    _bootstrap_blackbox_users(c, source_env, E2E_EMAIL, E2E_PASSWORD, E2E_USERNAME, E2E_ALT_EMAIL, E2E_ALT_PASSWORD, E2E_ALT_USERNAME)
+    _bootstrap_blackbox_users(c, follower_env, E2E_EMAIL, E2E_PASSWORD, E2E_USERNAME, E2E_ALT_EMAIL, E2E_ALT_PASSWORD, E2E_ALT_USERNAME)
+
+    source_base_url = f"http://127.0.0.1:{source_host_port}"
+    follower_base_url = f"http://127.0.0.1:{follower_host_port}"
+    _print_header("Leader/follower manual setup ready")
+    print(f"Leader URL:   {source_base_url}")
+    print(f"Follower URL: {follower_base_url}")
+    print(f"E2E owner email: {E2E_EMAIL}")
+    print(f"E2E owner password: {E2E_PASSWORD}")
+    print("Next steps:")
+    print("1. Create read-only follower tournament on follower backend.")
+    print("2. Create normal leader tournament on leader backend.")
+    print("3. Configure leader sync_target_url to follower /sync_state endpoint with shared token.")
+    print("4. Point frontend local leader view at leader URL and remote view at follower URL.")
+    print("5. Tear down with: inv docker-blackbox-follow-down")
+
+
 @task(name="docker-blackbox-follow-down")
 def docker_blackbox_follow_down(
     c,