diff --git a/pre_commit/constants.py b/pre_commit/constants.py
index a406fc22..8a52a03c 100644
--- a/pre_commit/constants.py
+++ b/pre_commit/constants.py
@@ -1,7 +1,7 @@
 
 CONFIG_FILE = '.pre-commit-config.yaml'
 
-PRE_COMMIT_DIR = '.pre-commit-files'
+HOOKS_WORKSPACE = '.pre-commit-files'
 
 MANIFEST_FILE = 'manifest.yaml'
 
diff --git a/pre_commit/git.py b/pre_commit/git.py
index d72008d0..7f057b2d 100644
--- a/pre_commit/git.py
+++ b/pre_commit/git.py
@@ -1,23 +1,18 @@
 import os
 import pkg_resources
 
-import pre_commit.constants as C
 from plumbum import local
 
 
+# TODO: optimization: memoize based on local.cwd.getpath()
 def get_root():
     return local['git']['rev-parse', '--show-toplevel']().strip()
 
+
 def get_pre_commit_path():
     return os.path.join(get_root(), '.git/hooks/pre-commit')
 
 
-def get_pre_commit_dir_path():
-    return os.path.join(get_root(), C.PRE_COMMIT_DIR)
-
-def create_pre_commit_package_dir():
-    local.path(get_pre_commit_dir_path()).mkdir()
-
 def create_pre_commit():
     path = get_pre_commit_path()
     pre_commit_file = pkg_resources.resource_filename('pre_commit', 'resources/pre-commit.sh')
@@ -28,4 +23,6 @@ def remove_pre_commit():
     local.path(get_pre_commit_path()).delete()
 
 
-
+def get_head_sha(git_repo_path):
+    with local.cwd(git_repo_path):
+        return (local['git']['rev-parse', 'HEAD'])().strip()
\ No newline at end of file
diff --git a/pre_commit/hooks_workspace.py b/pre_commit/hooks_workspace.py
new file mode 100644
index 00000000..e79ad2b9
--- /dev/null
+++ b/pre_commit/hooks_workspace.py
@@ -0,0 +1,20 @@
+
+import contextlib
+import os.path
+from plumbum import local
+
+import pre_commit.constants as C
+from pre_commit import git
+
+
+def get_pre_commit_dir_path():
+    return os.path.join(git.get_root(), C.HOOKS_WORKSPACE)
+
+@contextlib.contextmanager
+def in_hooks_workspace():
+    """Change into the hooks workspace.  If it does not exist create it."""
+    if not os.path.exists(get_pre_commit_dir_path()):
+        local.path(get_pre_commit_dir_path()).mkdir()
+
+    with local.cwd(get_pre_commit_dir_path()):
+        yield
\ No newline at end of file
diff --git a/pre_commit/repo_installer.py b/pre_commit/repo_installer.py
index 322950a0..9ec0673c 100644
--- a/pre_commit/repo_installer.py
+++ b/pre_commit/repo_installer.py
@@ -1,46 +1,44 @@
-import contextlib
 
+import contextlib
 from plumbum import local
-from pre_commit import git
+
+from pre_commit.hooks_workspace import in_hooks_workspace
 
 
 class RepoInstaller(object):
-    def __init__(self, git_repo_path, sha):
-        self.git_repo_path = git_repo_path
-        self.sha = sha
+    def __init__(self, repo_config):
+        self.repo_config = repo_config
+
+    @property
+    def repo_url(self):
+        return self.repo_config['repo']
+
+    @property
+    def sha(self):
+        return self.repo_config['sha']
 
     @contextlib.contextmanager
     def in_checkout(self):
-        with local.cwd(git.get_pre_commit_dir_path()):
+        with in_hooks_workspace():
             with local.cwd(self.sha):
                 yield
 
     def create(self):
-        git.create_pre_commit_package_dir()
-
-        with local.cwd(git.get_pre_commit_dir_path()):
+        with in_hooks_workspace():
             if local.path(self.sha).exists():
                 # Project already exists, no reason to re-create it
                 return
 
-            local['git']['clone', self.git_repo_path, self.sha]()
+            local['git']['clone', self.repo_url, self.sha]()
             with self.in_checkout():
                 local['git']['checkout', self.sha]()
 
     def install(self):
+        # Create if we have not already
+        self.create()
         # TODO: need to take in the config here and determine if we actually
         # need to run any installers (and what languages to install)
         with self.in_checkout():
             if local.path('setup.py').exists():
                 local['virtualenv']['py_env']()
                 local['bash']['-c', 'source py_env/bin/activate && pip install .']()
-
-
-def create_repo_in_env(git_repo_path, sha):
-    project = RepoInstaller(git_repo_path, sha)
-    project.create()
-
-def install_pre_commit(git_repo_path, sha):
-    project = RepoInstaller(git_repo_path, sha)
-    project.create()
-    project.install()
\ No newline at end of file
diff --git a/tests/conftest.py b/tests/conftest.py
index 377a7bb5..aa92ff11 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -1,8 +1,14 @@
+from __future__ import absolute_import
 
+import jsonschema
 import pytest
-import pre_commit.constants as C
+import time
 from plumbum import local
 
+import pre_commit.constants as C
+from pre_commit import git
+from pre_commit.clientlib.validate_config import CONFIG_JSON_SCHEMA
+
 
 @pytest.yield_fixture
 def empty_git_dir(tmpdir):
@@ -11,10 +17,9 @@ def empty_git_dir(tmpdir):
         yield tmpdir.strpath
 
 
-
 def add_and_commit():
     local['git']['add', '.']()
-    local['git']['commit', '-m', 'random commit']()
+    local['git']['commit', '-m', 'random commit {0}'.format(time.time())]()
 
 
 @pytest.yield_fixture
@@ -42,8 +47,7 @@ hooks:
 
 @pytest.yield_fixture
 def python_pre_commit_git_repo(dummy_pre_commit_hooks_git_repo):
-    local.path('setup.py').write(
-"""
+    local.path('setup.py').write("""
 from setuptools import find_packages
 from setuptools import setup
 
@@ -53,7 +57,7 @@ setup(
     packages=find_packages('.'),
     entry_points={
         'console_scripts': [
-            'entry = foo.main:func'
+            'foo = foo.main:func'
         ],
     }
 )
@@ -66,15 +70,28 @@ setup(
 
     with local.cwd(foo_module):
         local.path('__init__.py').write('')
-        local.path('main.py').write(
-"""
-
+        local.path('main.py').write("""
 def func():
     return 0
-
 """
         )
 
     add_and_commit()
 
     yield dummy_pre_commit_hooks_git_repo
+
+
+@pytest.fixture
+def config_for_python_pre_commit_git_repo(python_pre_commit_git_repo):
+    config = {
+        'repo': python_pre_commit_git_repo,
+        'sha': git.get_head_sha(python_pre_commit_git_repo),
+        'hooks': [{
+            'id': 'foo',
+            'files': '*.py',
+        }],
+    }
+
+    jsonschema.validate([config], CONFIG_JSON_SCHEMA)
+
+    return config
\ No newline at end of file
diff --git a/tests/git_test.py b/tests/git_test.py
index 9f413294..7dc5d05e 100644
--- a/tests/git_test.py
+++ b/tests/git_test.py
@@ -16,7 +16,9 @@ def test_get_root(empty_git_dir):
 
 
 def test_get_pre_commit_path(empty_git_dir):
-    assert git.get_pre_commit_path() == '{0}/.git/hooks/pre-commit'.format(empty_git_dir)
+    assert git.get_pre_commit_path() == '{0}/.git/hooks/pre-commit'.format(
+        empty_git_dir,
+    )
 
 
 def test_create_pre_commit(empty_git_dir):
diff --git a/tests/hooks_workspace_test.py b/tests/hooks_workspace_test.py
new file mode 100644
index 00000000..e69de29b
diff --git a/tests/repo_installer_test.py b/tests/repo_installer_test.py
index 00ad5b81..12c89c33 100644
--- a/tests/repo_installer_test.py
+++ b/tests/repo_installer_test.py
@@ -2,31 +2,46 @@ import os
 
 import jsonschema
 import pytest
-from plumbum import local
+from pre_commit import git
 
 import pre_commit.constants as C
 from pre_commit.clientlib.validate_config import CONFIG_JSON_SCHEMA
-from pre_commit.repo_installer import create_repo_in_env
-from pre_commit.repo_installer import install_pre_commit
+from pre_commit.repo_installer import RepoInstaller
 
 
-def get_sha(git_repo):
-    with local.cwd(git_repo):
-        return (local['git']['log', '--format="%H"'] | local['head']['-n1'])().strip('"\n')
+@pytest.fixture
+def dummy_repo_config(dummy_git_repo):
+    # This is not a valid config, but it is pretty close
+    return {
+        'repo': dummy_git_repo,
+        'sha': git.get_head_sha(dummy_git_repo),
+        'hooks': [],
+    }
+
 
 @pytest.mark.integration
-def test_create_repo_in_env(empty_git_dir, dummy_git_repo):
-    sha = get_sha(dummy_git_repo)
-    create_repo_in_env(dummy_git_repo, sha)
+def test_create_repo_in_env(dummy_repo_config, dummy_git_repo):
+    repo_installer = RepoInstaller(dummy_repo_config)
+    repo_installer.create()
 
-    assert os.path.exists(os.path.join(dummy_git_repo, C.PRE_COMMIT_DIR, sha))
+    assert os.path.exists(
+        os.path.join(dummy_git_repo, C.HOOKS_WORKSPACE, repo_installer.sha),
+    )
 
 @pytest.mark.integration
-def test_install_python_repo_in_env(empty_git_dir, python_pre_commit_git_repo):
-    sha = get_sha(python_pre_commit_git_repo)
-    install_pre_commit(python_pre_commit_git_repo,  sha)
+def test_install_python_repo_in_env(python_pre_commit_git_repo, config_for_python_pre_commit_git_repo):
+    repo_installer = RepoInstaller(config_for_python_pre_commit_git_repo)
+    # TODO: do we need create here?
+    repo_installer.install()
 
-    assert os.path.exists(os.path.join(python_pre_commit_git_repo, C.PRE_COMMIT_DIR, sha, 'py_env'))
+    assert os.path.exists(
+        os.path.join(
+            python_pre_commit_git_repo,
+            C.HOOKS_WORKSPACE,
+            repo_installer.sha,
+            'py_env',
+        ),
+    )
 
 
 @pytest.fixture
@@ -34,28 +49,14 @@ def simple_config(python_pre_commit_git_repo):
     config = [
         {
             'repo': python_pre_commit_git_repo,
-            'sha': get_sha(python_pre_commit_git_repo),
+            'sha': git.get_head_sha(python_pre_commit_git_repo),
             'hooks': [
                 {
                     'id': 'foo',
                     'files': '*.py',
-                    }
+                },
             ],
         },
     ]
     jsonschema.validate(config, CONFIG_JSON_SCHEMA)
     return config
-
-
-@pytest.mark.integration
-def test_install_config(empty_git_dir, python_pre_commit_git_repo, simple_config):
-    for repo in simple_config:
-        install_pre_commit(repo['repo'], repo['sha'])
-
-    assert os.path.exists(
-        os.path.join(
-            python_pre_commit_git_repo,
-            C.PRE_COMMIT_DIR, simple_config[0]['sha'],
-            'py_env',
-        ),
-    )
\ No newline at end of file