diff --git a/bundlewrap/groups.py b/bundlewrap/groups.py
index 406a85a3..8753a87f 100644
--- a/bundlewrap/groups.py
+++ b/bundlewrap/groups.py
@@ -4,6 +4,7 @@
 import bwkeepass as keepass
 
 from bundlewrap.utils import error_context
+from bundlewrap.utils.dicts import merge_dict
 
 for group in Path(join(repo_path, "groups")).rglob("*.py"):
     with error_context(filename=str(group)):
diff --git a/bundlewrap/groups/rooms.py b/bundlewrap/groups/rooms.py
index d1ef8fed..258f3b3a 100644
--- a/bundlewrap/groups/rooms.py
+++ b/bundlewrap/groups/rooms.py
@@ -10,6 +10,7 @@
     80, # muccc
     81, # hacc
     96, # kunsi
+    ('c4', 97),
     98, # derpeter
     191, # seibert
 )
@@ -34,3 +35,22 @@
 groups['saal28']['metadata']['users'] = {
     'equinox': {},
 }
+
+groups['saalc4']['metadata'] = merge_dict(
+    groups['saalc4']['metadata'],
+    {
+        'firewall': {
+            'port_rules': {
+                '*': {
+                    'rfc1918',
+                },
+            },
+        },
+        'users': {
+            'florob': {},
+            'florolf': {},
+            'ike': {},
+            'qb': {},
+        },
+    }
+)
diff --git a/bundlewrap/nodes/encoderc4.toml b/bundlewrap/nodes/encoderc4.toml
new file mode 100644
index 00000000..5b62ab6b
--- /dev/null
+++ b/bundlewrap/nodes/encoderc4.toml
@@ -0,0 +1,33 @@
+groups = ["debian-bookworm"]
+
+[metadata]
+hostname = "encoderc4.labor.koeln.ccc.de"
+
+[metadata.crs-worker.secrets]
+encoding.secret = "!decrypt:encrypt$gAAAAABmhFbnelqRLAIVSSoulff5VhTMF4VwNWcQY1lFykx6ZBBKt7fgUJ1wK8N0koDCWdvpYv1njZCbX0czS9yG2k6lG1xKk7vcE8gbU8Lb7dAc-14Vv86rix8qIzk4cx482sRbzi7a"
+encoding.token = "!decrypt:encrypt$gAAAAABmhFbQ3RlhXKPjsmdxSQoHhjvIVrnFkFto_Kzq3utVXGTEDwTj8HcX1RqZGwETlkMz6iQOzAXsk3facY7u0BcQh3agDrqFeh7Sdg2wrodWgWqMJD99dOEnSM56HDccdFfdEuNI"
+
+[metadata.event]
+name = "OpenChaos"
+room_name = "C4"
+slug = "oc"
+
+[metadata.interfaces.enp0s31f6]
+ips = ["172.23.23.118/23", "10.73.97.3/24"]
+gateway4 = "172.23.23.1"
+
+[metadata.voctocore]
+streaming_auth_key = "!decrypt:encrypt$gAAAAABmhFXnPeqkBp1Q_dlLSCwub0LBbEro4zbFCihoenJiKlDAI8cDDN5uNOA8M4rgTMkSgEMLGGt7-sSbqzDTbUUIqOMSn51fZZRIfvU-reVtWMy5cnI="
+
+[metadata.voctocore.sources.cam1]
+devicenumber = 1
+mode = "1080i50"
+
+[metadata.voctocore.sources.slides]
+devicenumber = 0
+mode = "1080p60"
+hdmi = true
+
+[metadata.voctocore.audio.original]
+streams = "0+1"
+input = "cam1"