diff --git a/.coveragerc b/.coveragerc
deleted file mode 100644
index b16a2ae1..00000000
--- a/.coveragerc
+++ /dev/null
@@ -1,32 +0,0 @@
-[run]
-
-source = extension_helpers
-
-omit =
-   extension_helpers/*/setup_package.py
-   extension_helpers/tests/*
-   extension_helpers/conftest.py
-
-[report]
-
-omit =
-   extension_helpers/*/setup_package.py
-   extension_helpers/tests/*
-   extension_helpers/conftest.py
-
-exclude_lines =
-   # Have to re-enable the standard pragma
-   pragma: no cover
-
-   # Don't complain about packages we have installed
-   except ImportError
-
-   # Don't complain if tests don't hit assertions
-   raise AssertionError
-   raise NotImplementedError
-
-   # Don't complain about script hooks
-   def main\(.*\):
-
-   # Ignore branches that don't pertain to this version of Python
-   pragma: py{ignore_python_version}
diff --git a/CHANGES.rst b/CHANGES.rst
index 2608991d..344313db 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -5,6 +5,8 @@
 
 * Removed any direct usage of distutils. [#34]
 
+* Remove support for the undocumented --compiler argument to setup.py. [#36]
+
 0.1 (2019-12-18)
 ----------------
 
diff --git a/extension_helpers/__init__.py b/extension_helpers/__init__.py
index 77362205..5ccfe0c5 100644
--- a/extension_helpers/__init__.py
+++ b/extension_helpers/__init__.py
@@ -1,5 +1,4 @@
-from ._distutils_helpers import get_compiler
 from ._openmp_helpers import add_openmp_flags_if_available
-from ._setup_helpers import get_extensions, pkg_config
+from ._setup_helpers import get_compiler, get_extensions, pkg_config
 from ._utils import import_file, write_if_different
 from .version import version as __version__
diff --git a/extension_helpers/_distutils_helpers.py b/extension_helpers/_distutils_helpers.py
deleted file mode 100644
index 859932de..00000000
--- a/extension_helpers/_distutils_helpers.py
+++ /dev/null
@@ -1,109 +0,0 @@
-"""
-This module contains various utilities for introspecting the distutils
-module and the setup process.
-
-Some of these utilities require the
-`extension_helpers.setup_helpers.register_commands` function to be called first,
-as it will affect introspection of setuptools command-line arguments.  Other
-utilities in this module do not have that restriction.
-"""
-
-import os
-import sys
-
-from setuptools.command.build_ext import new_compiler
-from setuptools.dist import Distribution
-from setuptools.errors import DistutilsError
-
-from ._utils import silence
-
-__all__ = ['get_compiler']
-
-
-def get_dummy_distribution():
-    """
-    Returns a distutils Distribution object used to instrument the setup
-    environment before calling the actual setup() function.
-    """
-
-    # Pre-parse the Distutils command-line options and config files to if
-    # the option is set.
-    dist = Distribution({'script_name': os.path.basename(sys.argv[0]),
-                         'script_args': sys.argv[1:]})
-
-    with silence():
-        try:
-            dist.parse_config_files()
-            dist.parse_command_line()
-        except (DistutilsError, AttributeError, SystemExit):
-            # Let distutils handle DistutilsErrors itself AttributeErrors can
-            # get raise for ./setup.py --help SystemExit can be raised if a
-            # display option was used, for example
-            pass
-
-    return dist
-
-
-def get_distutils_option(option, commands):
-    """ Returns the value of the given distutils option.
-
-    Parameters
-    ----------
-    option : str
-        The name of the option
-
-    commands : list of str
-        The list of commands on which this option is available
-
-    Returns
-    -------
-    val : str or None
-        the value of the given distutils option. If the option is not set,
-        returns None.
-    """
-
-    dist = get_dummy_distribution()
-
-    for cmd in commands:
-        cmd_opts = dist.command_options.get(cmd)
-        if cmd_opts is not None and option in cmd_opts:
-            return cmd_opts[option][1]
-    else:
-        return None
-
-
-def get_distutils_build_option(option):
-    """ Returns the value of the given distutils build option.
-
-    Parameters
-    ----------
-    option : str
-        The name of the option
-
-    Returns
-    -------
-    val : str or None
-        The value of the given distutils build option. If the option
-        is not set, returns None.
-    """
-    return get_distutils_option(option, ['build', 'build_ext', 'build_clib'])
-
-
-def get_compiler():
-    """
-    Determines the compiler that will be used to build extension modules.
-
-    Returns
-    -------
-    compiler : str
-        The compiler option specified for the build, build_ext, or build_clib
-        command; or the default compiler for the platform if none was
-        specified.
-
-    """
-
-    compiler = get_distutils_build_option('compiler')
-    if compiler is None:
-        return new_compiler().compiler_type
-
-    return compiler
diff --git a/extension_helpers/_openmp_helpers.py b/extension_helpers/_openmp_helpers.py
index d01d87c4..e7376d6f 100644
--- a/extension_helpers/_openmp_helpers.py
+++ b/extension_helpers/_openmp_helpers.py
@@ -22,7 +22,7 @@
 
 from setuptools.command.build_ext import customize_compiler, get_config_var, new_compiler
 
-from ._distutils_helpers import get_compiler
+from ._setup_helpers import get_compiler
 
 __all__ = ['add_openmp_flags_if_available']
 
diff --git a/extension_helpers/_setup_helpers.py b/extension_helpers/_setup_helpers.py
index f2f831cc..7e766da1 100644
--- a/extension_helpers/_setup_helpers.py
+++ b/extension_helpers/_setup_helpers.py
@@ -12,15 +12,30 @@
 from collections import defaultdict
 
 from setuptools import Extension, find_packages
+from setuptools.command.build_ext import new_compiler
 
-from ._distutils_helpers import get_compiler
 from ._utils import import_file, walk_skip_hidden
 
-__all__ = ['get_extensions', 'pkg_config']
+__all__ = ['get_compiler', 'get_extensions', 'pkg_config']
 
 log = logging.getLogger(__name__)
 
 
+def get_compiler():
+    """
+    Determines the compiler that will be used to build extension modules.
+
+    Returns
+    -------
+    compiler : str
+        The compiler option specified for the build, build_ext, or build_clib
+        command; or the default compiler for the platform if none was
+        specified.
+
+    """
+    return new_compiler().compiler_type
+
+
 def get_extensions(srcdir='.'):
     """
     Collect all extensions from Cython files and ``setup_package.py`` files.
diff --git a/extension_helpers/_utils.py b/extension_helpers/_utils.py
index c32a11b7..198fde1b 100644
--- a/extension_helpers/_utils.py
+++ b/extension_helpers/_utils.py
@@ -9,41 +9,6 @@
 __all__ = ['write_if_different', 'import_file']
 
 
-class _DummyFile(object):
-    """A noop writeable object."""
-
-    errors = ''
-
-    def write(self, s):
-        pass
-
-    def flush(self):
-        pass
-
-
-@contextlib.contextmanager
-def silence():
-    """A context manager that silences sys.stdout and sys.stderr."""
-
-    old_stdout = sys.stdout
-    old_stderr = sys.stderr
-    sys.stdout = _DummyFile()
-    sys.stderr = _DummyFile()
-    exception_occurred = False
-    try:
-        yield
-    except:  # noqa
-        exception_occurred = True
-        # Go ahead and clean up so that exception handling can work normally
-        sys.stdout = old_stdout
-        sys.stderr = old_stderr
-        raise
-
-    if not exception_occurred:
-        sys.stdout = old_stdout
-        sys.stderr = old_stderr
-
-
 if sys.platform == 'win32':
     import ctypes
 
@@ -162,7 +127,7 @@ def import_file(filename, name=None):
 
     if name is None:
         basename = os.path.splitext(filename)[0]
-        name = '_'.join(os.path.relpath(basename).split(os.sep)[1:])
+        name = '_'.join(os.path.abspath(basename).split(os.sep)[1:])
 
     if not os.path.exists(filename):
         raise ImportError('Could not import file {0}'.format(filename))
diff --git a/extension_helpers/tests/test_distutils_helpers.py b/extension_helpers/tests/test_distutils_helpers.py
deleted file mode 100644
index af8a7328..00000000
--- a/extension_helpers/tests/test_distutils_helpers.py
+++ /dev/null
@@ -1,7 +0,0 @@
-from .._distutils_helpers import get_compiler
-
-POSSIBLE_COMPILERS = ['unix', 'msvc', 'bcpp', 'cygwin', 'mingw32']
-
-
-def test_get_compiler():
-    assert get_compiler() in POSSIBLE_COMPILERS
diff --git a/extension_helpers/tests/test_setup_helpers.py b/extension_helpers/tests/test_setup_helpers.py
index abbf8dc4..9dc572d9 100644
--- a/extension_helpers/tests/test_setup_helpers.py
+++ b/extension_helpers/tests/test_setup_helpers.py
@@ -5,7 +5,7 @@
 
 import pytest
 
-from .._setup_helpers import get_extensions
+from .._setup_helpers import get_compiler, get_extensions
 from . import cleanup_import, run_setup
 
 extension_helpers_PATH = os.path.abspath(os.path.join(os.path.dirname(__file__), '..', '..'))  # noqa
@@ -19,6 +19,13 @@ def teardown_module(module):
         os.remove(tmpfile)
 
 
+POSSIBLE_COMPILERS = ['unix', 'msvc', 'bcpp', 'cygwin', 'mingw32']
+
+
+def test_get_compiler():
+    assert get_compiler() in POSSIBLE_COMPILERS
+
+
 def _extension_test_package(tmpdir, request, extension_type='c',
                             include_numpy=False):
     """Creates a simple test package with an extension module."""
diff --git a/extension_helpers/tests/test_utils.py b/extension_helpers/tests/test_utils.py
new file mode 100644
index 00000000..dc014886
--- /dev/null
+++ b/extension_helpers/tests/test_utils.py
@@ -0,0 +1,26 @@
+import os
+import time
+
+from .._utils import import_file, write_if_different
+
+
+def test_import_file(tmpdir):
+    filename = str(tmpdir / 'spam.py')
+    with open(filename, 'w') as f:
+        f.write('magic = 12345')
+    module = import_file(filename)
+    assert module.magic == 12345
+
+
+def test_write_if_different(tmpdir):
+    filename = str(tmpdir / 'test.txt')
+    write_if_different(filename, b'abc')
+    time1 = os.path.getmtime(filename)
+    time.sleep(0.01)
+    write_if_different(filename, b'abc')
+    time2 = os.path.getmtime(filename)
+    assert time2 == time1
+    time.sleep(0.01)
+    write_if_different(filename, b'abcd')
+    time3 = os.path.getmtime(filename)
+    assert time3 > time1
diff --git a/setup.cfg b/setup.cfg
index 31355d84..30b41f5a 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -56,3 +56,28 @@ balanced_wrapping = True
 include_trailing_comma = false
 length_sort = False
 length_sort_sections=stdlib
+
+[coverage:run]
+omit =
+  extension_helpers/*/setup_package.py
+  extension_helpers/tests/*
+  extension_helpers/conftest.py
+  */extension_helpers/*/setup_package.py
+  */extension_helpers/tests/*
+  */extension_helpers/conftest.py
+
+[coverage:report]
+exclude_lines =
+  # Have to re-enable the standard pragma
+  pragma: no cover
+  # Don't complain about packages we have installed
+  except ImportError
+  # Don't complain if tests don't hit assertions
+  raise AssertionError
+  raise NotImplementedError
+  # Don't complain about script hooks
+  def main\(.*\):
+  # Ignore branches that don't pertain to this version of Python
+  pragma: py{ignore_python_version}
+  # Don't complain about IPython completion helper
+  def _ipython_key_completions_
diff --git a/tox.ini b/tox.ini
index 28355849..eabe4e70 100644
--- a/tox.ini
+++ b/tox.ini
@@ -40,7 +40,7 @@ commands =
     dev: pip install setuptools_repo/ --no-build-isolation
     pip freeze
     test: python -c 'import setuptools; print(setuptools.__version__)'
-    test: pytest --pyargs extension_helpers {toxinidir}/docs --cov extension_helpers {posargs}
+    test: pytest --pyargs extension_helpers {toxinidir}/docs --cov extension_helpers --cov-config={toxinidir}/setup.cfg {posargs}
     build_docs: sphinx-build -W -b html . _build/html
 
 [testenv:py39-downstream]