diff --git a/Makefile b/Makefile
index 9398f9e7..11233580 100644
--- a/Makefile
+++ b/Makefile
@@ -130,7 +130,7 @@ ACCEPT_PY_PASS_FILES := $(patsubst %,build/%_py.pass,$(filter-out %/native_test,
 BENCHMARKS := $(patsubst %.py,%,$(wildcard benchmarks/*.py))
 BENCHMARK_BINS := $(patsubst %,build/%_benchmark,$(BENCHMARKS))
 
-TOOL_BINS = $(patsubst %,build/bin/%,benchcmp coverparse diffrange genmake pydeps)
+TOOL_BINS = $(patsubst %,build/bin/%,benchcmp coverparse diffrange genmake gentest pydeps)
 
 GOLINT_BIN = build/bin/golint
 PYLINT_BIN = build/bin/pylint
@@ -294,6 +294,7 @@ build/stdlib.mk: build/bin/genmake | $(STDLIB_SRCS)
 -include build/stdlib.mk
 
 $(patsubst %,build/src/__python__/%/module.go,$(STDLIB_PACKAGES)): $(COMPILER)
+$(patsubst %,build/src/__python__/%/module_test.go,$(STDLIB_PACKAGES)): build/bin/gentest $(COMPILER)
 $(patsubst %,build/src/__python__/%/module.d,$(STDLIB_PACKAGES)): build/bin/pydeps $(PYTHONPARSER_SRCS) $(COMPILER)
 $(patsubst %,$(PKG_DIR)/__python__/%.a,$(STDLIB_PACKAGES)): $(RUNTIME)
 
diff --git a/tools/genmake b/tools/genmake
index c13465a5..06c396e9 100755
--- a/tools/genmake
+++ b/tools/genmake
@@ -28,11 +28,13 @@ parser.add_argument('-all_target', default='all',
                     help='make target that will build all modules')
 
 
-def _PrintRule(target, prereqs, rules):
+def _PrintRule(target, prereqs, rules, echo_debug=False):
   print '{}: {}'.format(target, ' '.join(prereqs))
   if rules:
     print '\t@mkdir -p $(@D)'
     for rule in rules:
+      if echo_debug:
+        print '\t@echo @{}'.format(rule)
       print '\t@{}'.format(rule)
   print
 
@@ -67,9 +69,19 @@ def main(args):
       modname = basename.replace(os.sep, '.')
       ar_name = os.path.join(pkg_dir, '__python__', basename + '.a')
       go_file = os.path.join(pydir, basename, 'module.go')
+      gotest_file = os.path.join(pydir, basename, 'module_test.go')
+      ar_deps = [go_file]
       _PrintRule(go_file,
                  [os.path.join(dirpath, filename)],
-                 ['grumpc -modname={} $< > $@'.format(modname)])
+                 ['grumpc -modname={} $< > $@'.format(modname)],
+                 echo_debug=True)
+      if modname.endswith(('_test', '_tests')):
+        ar_deps.append(gotest_file)
+        _PrintRule(gotest_file,
+                   [os.path.join(dirpath, filename)],
+                   ['gentest -modname={} > $@'.format(modname)],
+                   echo_debug=True)
+
       recipe = (r"""pydeps -modname=%s $< | awk '{gsub(/\./, "/", $$0); """
                 r"""print "%s: %s/__python__/" $$0 ".a"}' > $@""")
       dep_file = os.path.join(pydir, basename, 'module.d')
@@ -77,7 +89,7 @@ def main(args):
                  [recipe % (modname, ar_name, pkg_dir)])
       go_package = '__python__/' + basename.replace(os.sep, '/')
       recipe = 'go tool compile -o $@ -p {} -complete -I {} -pack $<'
-      _PrintRule(ar_name, [go_file], [recipe.format(go_package, pkg_dir)])
+      _PrintRule(ar_name, ar_deps, [recipe.format(go_package, pkg_dir)])
       if args.all_target:
         _PrintRule(args.all_target, [ar_name], [])
       print '-include {}\n'.format(dep_file)
diff --git a/tools/gentest b/tools/gentest
new file mode 100755
index 00000000..ae957270
--- /dev/null
+++ b/tools/gentest
@@ -0,0 +1,100 @@
+#!/usr/bin/env python
+
+# Copyright 2016 Google Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""gentest creates a Golang module_test.go from a Python file, for coverage.
+
+Usage: $ gentest -m <module>             # Create test from the named module.
+"""
+
+import argparse
+import os
+import sys
+import textwrap
+
+from grumpy.compiler import imputil
+
+parser = argparse.ArgumentParser()
+parser.add_argument('-modname', required=True,
+                    help='Module to generate a _test.go file to')
+
+
+template = textwrap.dedent("""
+  package %s
+  import (
+  \t"testing"
+  \t"grumpy"
+  \t%s
+  )
+  func TestRunCode(t *testing.T) {
+  \tgrumpy.ImportModule(grumpy.NewRootFrame(), "traceback")
+  \tif grumpy.RunMain(Code) != 0 {
+  \t\tt.Fail()
+  \t}
+  }
+""")
+
+
+def _package_name(modname):
+  if modname.startswith('__go__/'):
+    return '__python__/' + modname
+  return '__python__/' + modname.replace('.', '/')
+
+
+def _get_gopath():
+  gopath = os.getenv('GOPATH', None)
+  if not gopath:
+    print >> sys.stderr, 'GOPATH not set'
+    raise RuntimeError('GOPATH not set')
+  return gopath
+
+
+def main(args):
+  modname = args.modname
+  gopath = _get_gopath()
+  workdir = 'build'   # It is ok _right now_
+  py_dir = os.path.join(workdir, 'src', '__python__')
+  mod_dir = os.path.join(py_dir, modname.replace('.', '/'))
+
+  script = os.path.join(py_dir, '%s.py' % modname.replace('.', '/'))
+  gopath = gopath + os.pathsep + workdir
+  testfile_modname = modname[:-5] if modname.endswith('_test') else modname
+  testfile_modname = testfile_modname.split('.')[-1]
+
+  if not os.path.isfile(script):
+    return  # The script does not exist. And is OK!
+
+  names = imputil.calculate_transitive_deps(modname, script, gopath)
+
+  # Find the script associated with the given module.
+  for d in gopath.split(os.pathsep):
+    script = imputil.find_script(os.path.join(d, 'src', '__python__'), modname)
+    if script:
+      break
+  else:
+    raise RuntimeError("can't find module %s", modname)
+
+  names = imputil.calculate_transitive_deps(modname, script, gopath)
+  # Make sure traceback is available in all Python binaries.
+  names.add('traceback')
+
+  imports = '\n\t'.join('_ "%s"' % _package_name(name) for name in names)
+
+  testfile_contents = template % (testfile_modname, imports)
+  with open(os.path.join(mod_dir, 'module_test.go'), 'w') as go_testfile:
+    go_testfile.write(testfile_contents)
+
+
+if __name__ == '__main__':
+  sys.exit(main(parser.parse_args()))
diff --git a/tools/grumpc b/tools/grumpc
index 53837738..d3ddb9fa 100755
--- a/tools/grumpc
+++ b/tools/grumpc
@@ -23,6 +23,7 @@ import argparse
 import os
 import sys
 import textwrap
+from StringIO import StringIO
 
 from grumpy.compiler import block
 from grumpy.compiler import imputil
@@ -34,6 +35,10 @@ from grumpy import pythonparser
 parser = argparse.ArgumentParser()
 parser.add_argument('script', help='Python source filename')
 parser.add_argument('-modname', default='__main__', help='Python module name')
+parser.add_argument('-output', default=None,
+                    help='Golang output file path (defaults to stdout)')
+parser.add_argument('-astest', default=False, action='store_true',
+                    help='Output as a test suite.')
 
 
 def main(args):
@@ -49,8 +54,9 @@ def main(args):
 
   with open(args.script) as py_file:
     py_contents = py_file.read()
+
   try:
-    mod = pythonparser.parse(py_contents)
+    parsed_module = pythonparser.parse(py_contents)
   except SyntaxError as e:
     print >> sys.stderr, '{}: line {}: invalid syntax: {}'.format(
         e.filename, e.lineno, e.text)
@@ -58,7 +64,7 @@ def main(args):
 
   # Do a pass for compiler directives from `from __future__ import *` statements
   try:
-    future_node, future_features = imputil.parse_future_features(mod)
+    future_node, future_features = imputil.parse_future_features(parsed_module)
   except util.CompileError as e:
     print >> sys.stderr, str(e)
     return 2
@@ -66,39 +72,80 @@ def main(args):
   importer = imputil.Importer(gopath, args.modname, args.script,
                               future_features.absolute_import)
   full_package_name = args.modname.replace('.', '/')
-  mod_block = block.ModuleBlock(importer, full_package_name, args.script,
-                                py_contents, future_features)
+  module_block = block.ModuleBlock(importer, full_package_name, args.script,
+                                   py_contents, future_features)
 
-  visitor = stmt.StatementVisitor(mod_block, future_node)
+  visitor = stmt.StatementVisitor(module_block, future_node)
   # Indent so that the module body is aligned with the goto labels.
   with visitor.writer.indent_block():
     try:
-      visitor.visit(mod)
+      visitor.visit(parsed_module)
     except util.ParseError as e:
       print >> sys.stderr, str(e)
       return 2
 
-  writer = util.Writer(sys.stdout)
+  go_result = StringIO()
+  writer = util.Writer(go_result)
   tmpl = textwrap.dedent("""\
       package $package
       import πg "grumpy"
+      $import_testing
       var Code *πg.Code
       func init() {
       \tCode = πg.NewCode("<module>", $script, nil, 0, func(πF *πg.Frame, _ []*πg.Object) (*πg.Object, *πg.BaseException) {
       \t\tvar πR *πg.Object; _ = πR
       \t\tvar πE *πg.BaseException; _ = πE""")
-  writer.write_tmpl(tmpl, package=args.modname.split('.')[-1],
+
+  go_package_name = args.modname.split('.')[-1]
+
+  # HACK: Should suppress _test from package name
+  # See: https://github.com/google/grumpy/issues/383#issuecomment-353394740
+  if go_package_name.endswith('_test'):
+    final_package_name = go_package_name[:-5]
+  else:
+    final_package_name = go_package_name
+
+  modname = util.go_str(args.modname)
+  writer.write_tmpl(tmpl, package=final_package_name,
+                    import_testing='import πt "testing"' if args.astest else '',
                     script=util.go_str(args.script))
   with writer.indent_block(2):
-    for s in sorted(mod_block.strings):
+    for s in sorted(module_block.strings):
       writer.write('ß{} := πg.InternStr({})'.format(s, util.go_str(s)))
-    writer.write_temp_decls(mod_block)
-    writer.write_block(mod_block, visitor.writer.getvalue())
+    writer.write_temp_decls(module_block)
+    writer.write_block(module_block, visitor.writer.getvalue())
   writer.write_tmpl(textwrap.dedent("""\
     \t\treturn nil, πE
     \t})
     \tπg.RegisterModule($modname, Code)
-    }"""), modname=util.go_str(args.modname))
+    }"""), modname=modname)
+
+  if args.astest:
+
+    tmpl = textwrap.dedent("""\
+
+      func TestRunCode(t *testing.T) {
+      \tinit()
+      \tπg.ImportModule(grumpy.NewRootFrame(), "traceback")
+      \t//πg.ImportModule(grumpy.NewRootFrame(), $modname)
+      \tπg.RunMain(Code)
+      }
+      """)
+
+    writer.write_tmpl(tmpl, modname=modname)
+
+  try:
+    if args.output:
+      go_output = open(args.output, 'w')
+    else:
+      go_output = sys.stdout
+  except IOError:
+    print >> sys.stderr, str(e)
+    return 2
+
+  go_result.seek(0)
+  go_output.write(go_result.read())
+  go_output.close()
   return 0