diff -Nurp mitogen-0.2.8.orig/ansible_mitogen/process.py mitogen-0.2.8/ansible_mitogen/process.py
--- mitogen-0.2.8.orig/ansible_mitogen/process.py	2019-08-18 10:46:38.000000000 -0500
+++ mitogen-0.2.8/ansible_mitogen/process.py	2019-08-25 15:02:06.618523928 -0500
@@ -178,66 +178,6 @@ def setup_pool(pool):
     LOG.debug('Service pool configured: size=%d', pool.size)
 
 
-def _setup_simplejson(responder):
-    """
-    We support serving simplejson for Python 2.4 targets on Ansible 2.3, at
-    least so the package's own CI Docker scripts can run without external
-    help, however newer versions of simplejson no longer support Python
-    2.4. Therefore override any installed/loaded version with a
-    2.4-compatible version we ship in the compat/ directory.
-    """
-    responder.whitelist_prefix('simplejson')
-
-    # issue #536: must be at end of sys.path, in case existing newer
-    # version is already loaded.
-    compat_path = os.path.join(os.path.dirname(__file__), 'compat')
-    sys.path.append(compat_path)
-
-    for fullname, is_pkg, suffix in (
-        (u'simplejson', True, '__init__.py'),
-        (u'simplejson.decoder', False, 'decoder.py'),
-        (u'simplejson.encoder', False, 'encoder.py'),
-        (u'simplejson.scanner', False, 'scanner.py'),
-    ):
-        path = os.path.join(compat_path, 'simplejson', suffix)
-        fp = open(path, 'rb')
-        try:
-            source = fp.read()
-        finally:
-            fp.close()
-
-        responder.add_source_override(
-            fullname=fullname,
-            path=path,
-            source=source,
-            is_pkg=is_pkg,
-        )
-
-
-def _setup_responder(responder):
-    """
-    Configure :class:`mitogen.master.ModuleResponder` to only permit
-    certain packages, and to generate custom responses for certain modules.
-    """
-    responder.whitelist_prefix('ansible')
-    responder.whitelist_prefix('ansible_mitogen')
-    _setup_simplejson(responder)
-
-    # Ansible 2.3 is compatible with Python 2.4 targets, however
-    # ansible/__init__.py is not. Instead, executor/module_common.py writes
-    # out a 2.4-compatible namespace package for unknown reasons. So we
-    # copy it here.
-    responder.add_source_override(
-        fullname='ansible',
-        path=ansible.__file__,
-        source=(ANSIBLE_PKG_OVERRIDE % (
-            ansible.__version__,
-            ansible.__author__,
-        )).encode(),
-        is_pkg=True,
-    )
-
-
 def increase_open_file_limit():
     """
     #549: in order to reduce the possibility of hitting an open files limit,
@@ -704,7 +644,6 @@ class MuxProcess(object):
             broker=self.broker,
             max_message_size=MAX_MESSAGE_SIZE,
         )
-        _setup_responder(self.router.responder)
         mitogen.core.listen(self.broker, 'shutdown', self._on_broker_shutdown)
         mitogen.core.listen(self.broker, 'exit', self._on_broker_exit)
         self.listener = mitogen.unix.Listener.build_stream(
diff -Nurp mitogen-0.2.8.orig/ansible_mitogen/runner.py mitogen-0.2.8/ansible_mitogen/runner.py
--- mitogen-0.2.8.orig/ansible_mitogen/runner.py	2019-08-18 10:46:38.000000000 -0500
+++ mitogen-0.2.8/ansible_mitogen/runner.py	2019-08-25 15:02:29.330419327 -0500
@@ -60,11 +60,7 @@ except ImportError:
     # Python 2.4
     ctypes = None
 
-try:
-    import json
-except ImportError:
-    # Python 2.4
-    import simplejson as json
+import json
 
 try:
     # Cannot use cStringIO as it does not support Unicode.
diff -Nurp mitogen-0.2.8.orig/ansible_mitogen/target.py mitogen-0.2.8/ansible_mitogen/target.py
--- mitogen-0.2.8.orig/ansible_mitogen/target.py	2019-08-18 10:46:38.000000000 -0500
+++ mitogen-0.2.8/ansible_mitogen/target.py	2019-08-25 15:03:01.952269082 -0500
@@ -56,10 +56,7 @@ import mitogen.parent
 import mitogen.service
 from mitogen.core import b
 
-try:
-    import json
-except ImportError:
-    import simplejson as json
+import json
 
 try:
     reduce
@@ -369,11 +366,6 @@ def init_child(econtext, log_level, cand
     LOG.setLevel(log_level)
     logging.getLogger('ansible_mitogen').setLevel(log_level)
 
-    # issue #536: if the json module is available, remove simplejson from the
-    # importer whitelist to avoid confusing certain Ansible modules.
-    if json.__name__ == 'json':
-        econtext.importer.whitelist.remove('simplejson')
-
     global _fork_parent
     if FORK_SUPPORTED:
         mitogen.parent.upgrade_router(econtext)
diff -Nurp mitogen-0.2.8.orig/mitogen/core.py mitogen-0.2.8/mitogen/core.py
--- mitogen-0.2.8.orig/mitogen/core.py	2019-08-18 10:46:38.000000000 -0500
+++ mitogen-0.2.8/mitogen/core.py	2019-08-25 15:03:19.254191435 -0500
@@ -1240,7 +1240,6 @@ class Importer(object):
     # construct it manually during startup.
     MITOGEN_PKG_CONTENT = [
         'buildah',
-        'compat',
         'debug',
         'doas',
         'docker',
diff -Nurp mitogen-0.2.8.orig/mitogen/master.py mitogen-0.2.8/mitogen/master.py
--- mitogen-0.2.8.orig/mitogen/master.py	2019-08-18 10:46:38.000000000 -0500
+++ mitogen-0.2.8/mitogen/master.py	2019-08-25 15:03:37.003112695 -0500
@@ -55,11 +55,6 @@ try:
 except ImportError:
     sysconfig = None
 
-if not hasattr(pkgutil, 'find_loader'):
-    # find_loader() was new in >=2.5, but the modern pkgutil.py syntax has
-    # been kept intentionally 2.3 compatible so we can reuse it.
-    from mitogen.compat import pkgutil
-
 import mitogen
 import mitogen.core
 import mitogen.minify
diff -Nurp mitogen-0.2.8.orig/mitogen/minify.py mitogen-0.2.8/mitogen/minify.py
--- mitogen-0.2.8.orig/mitogen/minify.py	2019-08-18 10:46:38.000000000 -0500
+++ mitogen-0.2.8/mitogen/minify.py	2019-08-25 15:03:55.050032632 -0500
@@ -37,10 +37,7 @@ except ImportError:
 
 import mitogen.core
 
-if sys.version_info < (2, 7, 11):
-    from mitogen.compat import tokenize
-else:
-    import tokenize
+import tokenize
 
 
 def minimize_source(source):