diff --git a/docker/webhook/entrypoint.sh b/docker/webhook/entrypoint.sh
index 26476c1..e996919 100755
--- a/docker/webhook/entrypoint.sh
+++ b/docker/webhook/entrypoint.sh
@@ -1,4 +1,3 @@
 #!/bin/sh
-# Substituiert ${DEPLOY_WEBHOOK_SECRET} im hooks.json-Template
-envsubst < /etc/webhook/hooks.json > /tmp/hooks.json
+sed "s|\${DEPLOY_WEBHOOK_SECRET}|${DEPLOY_WEBHOOK_SECRET}|g" /etc/webhook/hooks.json > /tmp/hooks.json
 exec webhook -hooks /tmp/hooks.json -verbose -port 9000 -urlprefix ""