diff --git a/darc/archive.py b/darc/archive.py
index 13fe4f26a..cc61c87e3 100644
--- a/darc/archive.py
+++ b/darc/archive.py
@@ -203,10 +203,12 @@ def extract_item(self, item, dest=None, start_cb=None, restore_attrs=True):
                 os.makedirs(os.path.dirname(path))
             # Hard link?
             if 'source' in item:
-                source = os.path.join(dest, item['source'])
-                if os.path.exists(path):
-                    os.unlink(path)
-                os.link(source, path)
+                def link_cb(_, __, item):
+                    source = os.path.join(dest, item['source'])
+                    if os.path.exists(path):
+                        os.unlink(path)
+                    os.link(source, path)
+                self.store.add_callback(link_cb, item)
             else:
                 def extract_cb(chunk, error, (id, i)):
                     if i == 0:
diff --git a/darc/archiver.py b/darc/archiver.py
index 4550b580c..a0256ca4b 100644
--- a/darc/archiver.py
+++ b/darc/archiver.py
@@ -137,8 +137,10 @@ def extract_cb(item):
             else:
                 archive.extract_item(item, args.dest, start_cb)
             if dirs and not item['path'].startswith(dirs[-1]['path']):
-                # Extract directories twice to make sure mtime is correctly restored
-                archive.extract_item(dirs.pop(-1), args.dest)
+                def cb(_, __, item):
+                    # Extract directories twice to make sure mtime is correctly restored
+                    archive.extract_item(item, args.dest)
+                store.add_callback(cb, dirs.pop(-1))
         store = self.open_store(args.archive)
         key = Key(store)
         manifest = Manifest(store, key)
@@ -343,7 +345,7 @@ def run(self, args=None):
         subparser.add_argument('src', metavar='SRC', type=location_validator(),
                                help='Store/Archive to list contents of')
 
-        subparser= subparsers.add_parser('verify', parents=[common_parser])
+        subparser = subparsers.add_parser('verify', parents=[common_parser])
         subparser.set_defaults(func=self.do_verify)
         subparser.add_argument('-i', '--include', dest='patterns',
                                type=IncludePattern, action='append',
diff --git a/darc/remote.py b/darc/remote.py
index 99d51cf5f..e36a3a488 100644
--- a/darc/remote.py
+++ b/darc/remote.py
@@ -125,7 +125,7 @@ def cmd(self, cmd, args, callback=None, callback_data=None):
         self.odata.append(msgpack.packb((1, self.msgid, cmd, args)))
         self.recursion += 1
         if callback:
-            self.callbacks[self.msgid] = callback, callback_data
+            self.add_callback(callback, callback_data)
             if self.recursion > 1:
                 self.recursion -= 1
                 return
@@ -146,8 +146,7 @@ def cmd(self, cmd, args, callback=None, callback_data=None):
                         self.recursion -= 1
                         return res
                     else:
-                        c, d = self.callbacks.pop(msgid, (None, None))
-                        if c:
+                        for c, d in self.callbacks.pop(msgid, []):
                             c(res, error, d)
             elif self.odata and self.channel.send_ready():
                 data = self.odata.pop(0)
@@ -184,6 +183,9 @@ def put(self, id, data, callback=None, callback_data=None):
     def delete(self, id, callback=None, callback_data=None):
         return self.cmd('delete', (id, ), callback, callback_data)
 
+    def add_callback(self, cb, data):
+        self.callbacks.setdefault(self.msgid, []).append((cb, data))
+
     def flush_rpc(self, counter=None, backlog=0):
         counter = counter or self.notifier.enabled
         while counter > backlog:
@@ -199,8 +201,7 @@ def flush_rpc(self, counter=None, backlog=0):
                 self.unpacker.feed(self.channel.recv(BUFSIZE))
                 for type, msgid, error, res in self.unpacker:
                     self.notifier.enabled.dec()
-                    c, d = self.callbacks.pop(msgid, (None, None))
-                    if c:
+                    for c, d in self.callbacks.pop(msgid, []):
                         c(res, error, d)
                     if msgid == self.msgid:
                         return
diff --git a/darc/store.py b/darc/store.py
index 6a042e998..da98fe275 100644
--- a/darc/store.py
+++ b/darc/store.py
@@ -235,6 +235,9 @@ def delete(self, id):
     def flush_rpc(self, *args):
         pass
 
+    def add_callback(self, cb, data):
+        cb(None, None, data)
+
 
 class LoggedIO(object):