diff --git a/src/sakia/core/graph/explorer_graph.py b/src/sakia/core/graph/explorer_graph.py
index 420b4b48a4cc9b106188fd30cb9d3cbad434231e..a698e4648330f54d67dfbc41ebd00f5677a3cf35 100644
--- a/src/sakia/core/graph/explorer_graph.py
+++ b/src/sakia/core/graph/explorer_graph.py
@@ -77,14 +77,17 @@ class ExplorerGraph(BaseGraph):
                     logging.debug("New identity explored : {pubkey}".format(pubkey=current_identity.pubkey[:5]))
                     self.graph_changed.emit()
 
-                    certifier_list = await current_identity.unique_valid_certifiers_of(self.app.identities_registry,
-                                                                                             self.community)
+                    certifier_coro = asyncio.ensure_future(current_identity.unique_valid_certifiers_of(self.app.identities_registry,
+                                                                                             self.community))
+
+                    certified_coro = asyncio.ensure_future(current_identity.unique_valid_certified_by(self.app.identities_registry,
+                                                                                            self.community))
+
+                    certifier_list, certified_list = await asyncio.gather(certifier_coro, certified_coro)
+
                     await self.add_certifier_list(certifier_list, current_identity, identity)
                     logging.debug("New identity certifiers : {pubkey}".format(pubkey=current_identity.pubkey[:5]))
                     self.graph_changed.emit()
-
-                    certified_list = await current_identity.unique_valid_certified_by(self.app.identities_registry,
-                                                                                            self.community)
                     await self.add_certified_list(certified_list, current_identity, identity)
                     logging.debug("New identity certified : {pubkey}".format(pubkey=current_identity.pubkey[:5]))
                     self.graph_changed.emit()
diff --git a/src/sakia/core/graph/wot_graph.py b/src/sakia/core/graph/wot_graph.py
index 196c0f9188622b11e6a1eb13ecdf3829f6e13dc5..b80a6979f2b90ea4979eb9f8c08c07b7da77b958 100644
--- a/src/sakia/core/graph/wot_graph.py
+++ b/src/sakia/core/graph/wot_graph.py
@@ -1,4 +1,5 @@
 import logging
+import asyncio
 import networkx
 from .base_graph import BaseGraph
 from .constants import NodeStatus
@@ -65,14 +66,17 @@ class WoTGraph(BaseGraph):
 
         while len(explorable) > 0:
             current = explorable.pop()
-            certifier_list = await current.unique_valid_certifiers_of(self.app.identities_registry,
-                                                                                     self.community)
+            certifier_coro = asyncio.ensure_future(current.unique_valid_certifiers_of(self.app.identities_registry,
+                                                                                     self.community))
+            certified_coro = asyncio.ensure_future(current.unique_valid_certified_by(self.app.identities_registry,
+                                                                                    self.community))
+
+            certifier_list, certified_list = await asyncio.gather(certifier_coro, certified_coro)
+
             await self.add_certifier_list(certifier_list, current, account_identity)
             if to_identity.pubkey in [data['identity'].pubkey for data in certifier_list]:
                 return True
 
-            certified_list = await current.unique_valid_certified_by(self.app.identities_registry,
-                                                                                    self.community)
             await self.add_certified_list(certified_list, current, account_identity)
             if to_identity.pubkey in [data['identity'].pubkey for data in certified_list]:
                 return True
@@ -81,4 +85,5 @@ class WoTGraph(BaseGraph):
             for entry in certifier_list + certified_list:
                 if entry['identity'] not in explored + explorable:
                     explorable.append(entry['identity'])
-        return False
\ No newline at end of file
+
+        return False