diff --git a/mx-tester.yml b/mx-tester.yml
index 186d34b..94facba 100644
--- a/mx-tester.yml
+++ b/mx-tester.yml
@@ -9,6 +9,8 @@ up:
     - psql postgres://mjolnir-tester:mjolnir-test@localhost:8082/mjolnir-test-db -c "CREATE TABLE mjolnir (local_part VARCHAR(255), owner VARCHAR(255), management_room TEXT)"
     # Launch the reverse proxy, listening for connections *only* on the local host.
     - docker run --rm --network host --name mjolnir-test-reverse-proxy -p 127.0.0.1:8081:80 -v $MX_TEST_CWD/test/nginx.conf:/etc/nginx/nginx.conf:ro -d nginx
+    - yarn install
+    - npx ts-node src/appservice/cli.ts -r -u "http://host.docker.internal:9000"
     - cp mjolnir-registration.yaml $MX_TEST_SYNAPSE_DIR/data/
   after:
     # Wait until Synapse is ready