diff --git a/.ruby-version b/.ruby-version
index 5859406..aedc15b 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-2.2.3
+2.5.3
diff --git a/README.md b/README.md
index 773149b..8e4daac 100644
--- a/README.md
+++ b/README.md
@@ -152,7 +152,7 @@ https-portal:
   # ...
   environment:
     STAGE: local
-    DOMAINS: 'example.com => target.example.com/foo/bar' # Notice it's "=>" instead of the normal "->"
+    DOMAINS: 'example.com => https://target.example.com/foo/bar' # Notice it's "=>" instead of the normal "->"
 ```
 
 ### Automatic Container Discovery