diff --git a/dev-requirements.txt b/dev-requirements.txt
index a08abb2..5727d1e 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -1,4 +1,4 @@
-coverage==3.7.1
+coverage
 nose
 nose-cov
-testtools
\ No newline at end of file
+testtools
diff --git a/packer.py b/packer.py
index a50758f..33cc535 100644
--- a/packer.py
+++ b/packer.py
@@ -41,9 +41,8 @@ def __init__(self, packerfile, exc=None, only=None, vars=None,
         self.packer = sh.Command(exec_path)
         self.packer = self.packer.bake(**kwargs)
 
-    def build(
-            self, parallel=True, debug=False, force=False,
-            machine_readable=False):
+    def build(self, parallel=True, debug=False, force=False,
+              machine_readable=False):
         """Executes a `packer build`
 
         :param bool parallel: Run builders in parallel
@@ -74,8 +73,8 @@ def fix(self, to_file=None):
         result = self.packer_cmd()
         if to_file:
             with open(to_file, 'w') as f:
-                f.write(result.stdout)
-        result.fixed = json.loads(result.stdout)
+                f.write(result.stdout.decode())
+        result.fixed = json.loads(result.stdout.decode())
         return result
 
     def inspect(self, mrf=True):
@@ -115,7 +114,8 @@ def inspect(self, mrf=True):
 
         result = self.packer_cmd()
         if mrf:
-            result.parsed_output = self._parse_inspection_output(result.stdout)
+            result.parsed_output = self._parse_inspection_output(
+                                                        result.stdout.decode())
         else:
             result.parsed_output = None
         return result
diff --git a/setup.py b/setup.py
index 161d075..0aa8dd8 100644
--- a/setup.py
+++ b/setup.py
@@ -20,7 +20,7 @@ def read(*parts):
     description='A Python interface for Hashicorp\'s Packer',
     long_description=read('README.rst'),
     py_modules=['packer'],
-    install_requires=["sh==1.11"],
+    install_requires=["sh"],
     classifiers=[
         'Programming Language :: Python',
         'Natural Language :: English',
diff --git a/tests/resources/simple-test.json b/tests/resources/simple-test.json
new file mode 100644
index 0000000..58e8623
--- /dev/null
+++ b/tests/resources/simple-test.json
@@ -0,0 +1,10 @@
+{
+  "builders": [
+    {
+      "type": "null",
+      "ssh_host": "127.0.0.1",
+      "ssh_username": "root",
+      "ssh_password": "password"
+    }
+  ]
+}
diff --git a/tests/test_packer.py b/tests/test_packer.py
index 424e01d..1ec037b 100644
--- a/tests/test_packer.py
+++ b/tests/test_packer.py
@@ -5,7 +5,7 @@
 
 PACKER_PATH = '/usr/bin/packer'
 TEST_RESOURCES_DIR = 'tests/resources'
-TEST_PACKERFILE = os.path.join(TEST_RESOURCES_DIR, 'packerfile.json')
+TEST_PACKERFILE = os.path.join(TEST_RESOURCES_DIR, 'simple-test.json')
 TEST_BAD_PACKERFILE = os.path.join(TEST_RESOURCES_DIR, 'badpackerfile.json')
 
 
diff --git a/tox.ini b/tox.ini
index 0ed516a..307795b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,13 +1,8 @@
 # content of: tox.ini , put in same dir as setup.py
 [tox]
-envlist=flake8,py27,py26
+envlist=flake8,py27,py26,py35
 
-[testenv:py26]
-deps =
-    -rdev-requirements.txt
-commands=nosetests --with-cov --cov-report term-missing --cov packer tests -v
-
-[testenv:py27]
+[testenv]
 deps =
     -rdev-requirements.txt
 commands=nosetests --with-cov --cov-report term-missing --cov packer tests -v