diff --git a/src/allmydata/client.py b/src/allmydata/client.py
index 1eb72090f..1c5b68eb9 100644
--- a/src/allmydata/client.py
+++ b/src/allmydata/client.py
@@ -529,8 +529,6 @@ class _Client(node.Node, pollmixin.PollMixin):
         ps = self.config.get_config("client", "peers.preferred", "").split(",")
         preferred_peers = tuple([p.strip() for p in ps if p != ""])
 
-        from allmydata.node import create_tub, create_tub_options
-
         # this is temporary; create_client() should create a
         # storage-broker and pass it in -- that method already has
         # all these objects created...
diff --git a/src/allmydata/introducer/server.py b/src/allmydata/introducer/server.py
index 6b93a1841..c6fc81462 100644
--- a/src/allmydata/introducer/server.py
+++ b/src/allmydata/introducer/server.py
@@ -48,7 +48,6 @@ def create_introducer(basedir=u"."):
     )
 
     # XXX fix up imports etc (also: reactor)
-    from twisted.internet import reactor
     from allmydata.node import create_i2p_provider, create_tor_provider
     i2p_provider = create_i2p_provider(reactor, basedir, config)
     tor_provider = create_tor_provider(reactor, basedir, config)
diff --git a/src/allmydata/node.py b/src/allmydata/node.py
index 426293506..86ca49772 100644
--- a/src/allmydata/node.py
+++ b/src/allmydata/node.py
@@ -12,7 +12,6 @@ import tempfile
 from io import BytesIO
 from base64 import b32decode, b32encode
 
-from twisted.internet import reactor
 from twisted.python import log as twlog
 from twisted.application import service
 from twisted.python.failure import Failure
diff --git a/src/allmydata/test/cli/test_daemonize.py b/src/allmydata/test/cli/test_daemonize.py
index 2ec78c32c..c11331671 100644
--- a/src/allmydata/test/cli/test_daemonize.py
+++ b/src/allmydata/test/cli/test_daemonize.py
@@ -4,7 +4,6 @@ from mock import patch, Mock
 from StringIO import StringIO
 from sys import getfilesystemencoding
 from twisted.trial import unittest
-from twisted.internet import defer
 from allmydata.scripts import runner
 from allmydata.scripts.tahoe_daemonize import identify_node_type
 from allmydata.scripts.tahoe_daemonize import DaemonizeTahoeNodePlugin
diff --git a/src/allmydata/test/test_client.py b/src/allmydata/test/test_client.py
index 44d93ca87..3c8d76662 100644
--- a/src/allmydata/test/test_client.py
+++ b/src/allmydata/test/test_client.py
@@ -222,7 +222,7 @@ class Basic(testutil.ReallyEqualMixin, testutil.NonASCIIPathMixin, unittest.Test
                            "[storage]\n" + \
                            "enabled = true\n" + \
                            "reserved_space = bogus\n")
-        with self.assertRaises(ValueError) as ctx:
+        with self.assertRaises(ValueError):
             yield client.create_client(basedir)
 
     @defer.inlineCallbacks
diff --git a/src/allmydata/test/test_connections.py b/src/allmydata/test/test_connections.py
index ee0ccf65f..cafb6e3c1 100644
--- a/src/allmydata/test/test_connections.py
+++ b/src/allmydata/test/test_connections.py
@@ -8,7 +8,6 @@ from ..node import Node, PrivacyError, config_from_string
 from ..node import create_connection_handlers
 from ..node import create_i2p_provider, create_tor_provider
 from ..node import create_main_tub, _tub_portlocation
-from ..client import create_client_from_config
 from ..util import connection_status
 
 
@@ -161,7 +160,7 @@ class Tor(unittest.TestCase):
         )
         with self.assertRaises(ValueError) as ctx:
             tor_provider = create_tor_provider(reactor, 'BASEDIR', config)
-            h = tor_provider.get_tor_handler()
+            tor_provider.get_tor_handler()
         self.assertIn(
             "Unknown endpoint type: 'meow'",
             str(ctx.exception)
@@ -175,7 +174,7 @@ class Tor(unittest.TestCase):
         )
         with self.assertRaises(ValueError) as ctx:
             tor_provider = create_tor_provider(reactor, 'BASEDIR', config)
-            h = tor_provider.get_tor_handler()
+            tor_provider.get_tor_handler()
         self.assertIn(
             "invalid literal for int() with base 10: 'kumquat'",
             str(ctx.exception)
@@ -257,7 +256,7 @@ class I2P(unittest.TestCase):
         )
         with self.assertRaises(ValueError) as ctx:
             i2p_provider = create_i2p_provider(reactor, 'BASEDIR', config)
-            h = i2p_provider.get_i2p_handler()
+            i2p_provider.get_i2p_handler()
         self.assertIn(
             "must not set both sam.port and launch",
             str(ctx.exception)
diff --git a/src/allmydata/test/test_node.py b/src/allmydata/test/test_node.py
index 32042fa03..a58e2ce66 100644
--- a/src/allmydata/test/test_node.py
+++ b/src/allmydata/test/test_node.py
@@ -15,9 +15,8 @@ from foolscap.api import flushEventualQueue
 import foolscap.logging.log
 
 from twisted.application import service
-from allmydata.node import Node, formatTimeTahoeStyle, MissingConfigEntry, read_config, config_from_string, create_node_dir
-from allmydata.node import create_tub
 from allmydata.node import create_tub_options
+from allmydata.node import create_tub
 from allmydata.node import create_main_tub
 from allmydata.node import create_connection_handlers
 from allmydata.introducer.server import create_introducer
diff --git a/src/allmydata/test/test_system.py b/src/allmydata/test/test_system.py
index f46f9e104..cf77dd93c 100644
--- a/src/allmydata/test/test_system.py
+++ b/src/allmydata/test/test_system.py
@@ -784,7 +784,7 @@ class SystemTestMixin(pollmixin.PollMixin, testutil.StallMixin):
             c.setServiceParent(self.sparent)
         else:
             c.startService()
-        res = yield self.wait_for_connections()
+        yield self.wait_for_connections()
         defer.returnValue(c)
 
     def _check_connections(self):