1 files changed, 2 insertions, 1 deletions
diff --git a/readme.md b/readme.md
index 5d6fe8d..522e269 100644
--- a/readme.md
+++ b/readme.md
@@ -123,7 +123,8 @@ themselves; in that case the request is passed on.
   - Forwards the request as-is to some other server. the `x-real-ip` header is
     added to the request. Connection upgrades are handled by direct forwarding
     of network traffic.
-  - `backend`: socket address (string) to the backend server
+  - `backend`: IP socket address or absolute path to unix socket of the backend
+    server. (string)
   - `set_real_ip`: Sets the `X-Real-IP` header. (boolean)
   - `set_forwarded_for`: Sets the `X-Forwarded-For`, `X-Forwarded-Host`,
     `X-Forwaded-Proto`, `X-Forwarded-Scheme` and `X-Forwarded-Port` headers.