diff --git a/.circleci/config.yml b/.circleci/config.yml
index df181f058..56bc3e07e 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -211,7 +211,8 @@ jobs:
 
     environment:
       <<: *UTF_8_ENVIRONMENT
-      TAHOE_LAFS_TOX_ENVIRONMENT: "pypy27-coverage"
+      # We don't do coverage since it makes PyPy far too slow:
+      TAHOE_LAFS_TOX_ENVIRONMENT: "pypy27"
 
 
   c-locale:
diff --git a/.circleci/run-tests.sh b/.circleci/run-tests.sh
index 48f500280..764651c40 100755
--- a/.circleci/run-tests.sh
+++ b/.circleci/run-tests.sh
@@ -68,6 +68,10 @@ export SUBUNITREPORTER_OUTPUT_PATH="${SUBUNIT2}"
 export TAHOE_LAFS_TRIAL_ARGS="${TAHOE_LAFS_TRIAL_ARGS:---reporter=subunitv2-file --rterrors}"
 export PIP_NO_INDEX="1"
 
+# Make output unbuffered, so progress reports from subunitv2-file get streamed
+# and notify CircleCI we're still alive.
+export PYTHONUNBUFFERED=1
+
 if [ "${ALLOWED_FAILURE}" = "yes" ]; then
     alternative="true"
 else
diff --git a/newsfragments/3396.minor b/newsfragments/3396.minor
new file mode 100644
index 000000000..e69de29bb
diff --git a/newsfragments/3401.minor b/newsfragments/3401.minor
new file mode 100644
index 000000000..e69de29bb
diff --git a/src/allmydata/test/common.py b/src/allmydata/test/common.py
index dbd93df67..b69d58ab9 100644
--- a/src/allmydata/test/common.py
+++ b/src/allmydata/test/common.py
@@ -52,7 +52,6 @@ from twisted.internet.defer import inlineCallbacks, returnValue
 from twisted.internet.interfaces import IPullProducer
 from twisted.python import failure
 from twisted.python.filepath import FilePath
-from twisted.application import service
 from twisted.web.error import Error as WebError
 from twisted.internet.interfaces import (
     IStreamServerEndpointStringParser,
diff --git a/src/allmydata/test/common_py3.py b/src/allmydata/test/common_py3.py
index 36738d559..50fb02ff7 100644
--- a/src/allmydata/test/common_py3.py
+++ b/src/allmydata/test/common_py3.py
@@ -79,6 +79,28 @@ class ShouldFailMixin(object):
 
     def shouldFail(self, expected_failure, which, substring,
                    callable, *args, **kwargs):
+        """Assert that a function call raises some exception. This is a
+        Deferred-friendly version of TestCase.assertRaises() .
+
+        Suppose you want to verify the following function:
+
+         def broken(a, b, c):
+             if a < 0:
+                 raise TypeError('a must not be negative')
+             return defer.succeed(b+c)
+
+        You can use:
+            d = self.shouldFail(TypeError, 'test name',
+                                'a must not be negative',
+                                broken, -4, 5, c=12)
+        in your test method. The 'test name' string will be included in the
+        error message, if any, because Deferred chains frequently make it
+        difficult to tell which assertion was tripped.
+
+        The substring= argument, if not None, must appear in the 'repr'
+        of the message wrapped by this Failure, or the test will fail.
+        """
+
         assert substring is None or isinstance(substring, (bytes, unicode))
         d = defer.maybeDeferred(callable, *args, **kwargs)
         def done(res):
@@ -143,44 +165,3 @@ class LoggingServiceParent(service.MultiService):
     def log(self, *args, **kwargs):
         return log.msg(*args, **kwargs)
 
-
-class ShouldFailMixin(object):
-    def shouldFail(self, expected_failure, which, substring,
-                   callable, *args, **kwargs):
-        """Assert that a function call raises some exception. This is a
-        Deferred-friendly version of TestCase.assertRaises() .
-
-        Suppose you want to verify the following function:
-
-         def broken(a, b, c):
-             if a < 0:
-                 raise TypeError('a must not be negative')
-             return defer.succeed(b+c)
-
-        You can use:
-            d = self.shouldFail(TypeError, 'test name',
-                                'a must not be negative',
-                                broken, -4, 5, c=12)
-        in your test method. The 'test name' string will be included in the
-        error message, if any, because Deferred chains frequently make it
-        difficult to tell which assertion was tripped.
-
-        The substring= argument, if not None, must appear in the 'repr'
-        of the message wrapped by this Failure, or the test will fail.
-        """
-
-        assert substring is None or isinstance(substring, str)
-        d = defer.maybeDeferred(callable, *args, **kwargs)
-        def done(res):
-            if isinstance(res, failure.Failure):
-                res.trap(expected_failure)
-                if substring:
-                    message = repr(res.value.args[0])
-                    self.failUnless(substring in message,
-                                    "%s: substring '%s' not in '%s'"
-                                    % (which, substring, message))
-            else:
-                self.fail("%s was supposed to raise %s, not get '%s'" %
-                          (which, expected_failure, res))
-        d.addBoth(done)
-        return d
diff --git a/src/allmydata/test/test_system.py b/src/allmydata/test/test_system.py
index c80aeb45e..96fdfaba7 100644
--- a/src/allmydata/test/test_system.py
+++ b/src/allmydata/test/test_system.py
@@ -980,6 +980,8 @@ class CountingDataUploadable(upload.Data):
 
 class SystemTest(SystemTestMixin, RunBinTahoeMixin, unittest.TestCase):
 
+    timeout = 180
+
     def test_connections(self):
         self.basedir = "system/SystemTest/test_connections"
         d = self.set_up_nodes()