diff --git a/compose/docker-compose.yml b/compose/docker-compose.yml
index 7a959ce..eb2c191 100644
--- a/compose/docker-compose.yml
+++ b/compose/docker-compose.yml
@@ -22,7 +22,6 @@ x-op-app: &app
     DATABASE_URL: "${DATABASE_URL:-postgres://postgres:p4ssw0rd@db/openproject?pool=20&encoding=unicode&reconnect=true}"
     RAILS_MIN_THREADS: 4
     RAILS_MAX_THREADS: 16
-    USE_PUMA: "true"
     # set to true to enable the email receiving feature. See ./docker/cron for more options
     IMAP_ENABLED: "${IMAP_ENABLED:-false}"
   volumes: