diff --git a/bundles/matrix-synapse/metadata.py b/bundles/matrix-synapse/metadata.py
index 46f64ca..8a3175a 100644
--- a/bundles/matrix-synapse/metadata.py
+++ b/bundles/matrix-synapse/metadata.py
@@ -156,3 +156,20 @@ def nginx(metadata):
             'vhosts': vhosts
         },
     }
+
+@metadata_reactor.provides(
+    'matrix-synapse/trusted_key_servers',
+)
+def autotrust_our_own_servers(metadata):
+    domains = set()
+    for rnode in repo.nodes:
+        if not rnode.has_bundle('matrix-synapse'):
+            continue
+
+        domains.add(rnode.metadata.get('matrix-synapse/server_name'))
+
+    return {
+        'matrix-synapse': {
+            'trusted_key_servers': domains,
+        },
+    }