diff --git a/entrypoint.sh.tmpl b/entrypoint.sh.tmpl
index 9eb379b..cf8bc8f 100644
--- a/entrypoint.sh.tmpl
+++ b/entrypoint.sh.tmpl
@@ -1,3 +1,7 @@
 #!/bin/bash
 
+# https://github.com/matrix-org/synapse/tree/develop/docker#running-synapse
+# default user permissions for the synapse user
+chown 991:991 /data
+
 /start.py