diff --git a/README.md b/README.md
index 5044d15..b211119 100644
--- a/README.md
+++ b/README.md
@@ -15,7 +15,7 @@ up a ready-to-roll mongodb or openldap server, it does what it is supposed to.
 - [x] Add filtering to `find` command, to seach for tags or name
 - [ ] App port binding, i.e. phpmyadmin on 9000, phpcacheadmin on 9001
 - [ ] Make use of a `~/.serverenvs` to override envs for instances
-- [ ] Consider UDP?
+- [x] Consider UDP?
 
 ## Examples
 
@@ -53,6 +53,39 @@ Stopped mongo<other>
 $
 ```
 
+## Service definition
+
+Services are defined as JSON and should be put in the `registry` directory, which
+should be located in the same directory as the executable (when using phar) or in
+the project root when running from source.
+
+```json
+{
+  "$type": "service",
+  "name": "myservice",
+  "description": "My neat service",
+  "tags": [ "app", "neat" ],
+  "author": "Myself <myself@domain.tld>",
+  "image": "myself/myservice",
+  "ports": [ 
+    { "port": 1337, "info": "Neat port" },
+    { "port": 1337, "info": "Neat port (UDP)", "proto": "udp" }
+  ],
+  "persistence": [
+    { "path": "/data", "hint": "Fancy data" }
+  ],
+  "environment": {
+    "NEAT_ENV_VAR": "useful value",
+  },
+  "scripts": {
+    "setup": {
+      "info": "Launch the neat configuration tool",
+      "execute": "/app/setup.sh"
+    }
+  }
+}
+```
+
 
 ## FAQ
 
diff --git a/src/Container/ContainerManager.php b/src/Container/ContainerManager.php
index d1d1ec7..378ac7d 100644
--- a/src/Container/ContainerManager.php
+++ b/src/Container/ContainerManager.php
@@ -119,9 +119,10 @@ class ContainerManager
         foreach ($ports as $port) {
             $portNumber = intval($port['port']) + $portOffset;
             $target = array_key_exists('target',$port)?intval($port['target']):intval($port['port']);
+            $proto = $port['proto']??"tcp";
             $args[] = '-p';
-            $args[] = $portNumber.":".$target;
-            $mappedPorts[$port['info']] = $portNumber;
+            $args[] = $portNumber.":".$target."/".$proto;
+            $mappedPorts[$port['info']] = $portNumber."/".$proto;
         }
 
         // Get the paths to persist