diff --git a/Dockerfile b/Dockerfile
index 00bdaab..da2ae67 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -20,6 +20,7 @@ ENV RUNBOAT_BUILD_ENV='{"PGHOST": "postgres14.runboat-builds-db", "PGPORT": "543
 ENV RUNBOAT_BUILD_SECRET_ENV='{"PGPASSWORD": "..."}'
 ENV RUNBOAT_BUILD_TEMPLATE_VARS='{}'
 ENV RUNBOAT_GITHUB_TOKEN=
+ENV RUNBOAT_GITHUB_WEBHOOK_SECRET=
 ENV RUNBOAT_BASE_URL=https://runboat.example.com
 ENV RUNBOAT_ADDITIONAL_FOOTER_HTML=''