diff --git a/support/update-website.py b/support/update-website.py
index 416f49be..4683be30 100755
--- a/support/update-website.py
+++ b/support/update-website.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python
 
-import os, re, shutil, sys, tempfile
+import os, re, shutil, sys
 from subprocess import check_call
 
 class Git:
@@ -22,65 +22,68 @@ class Git:
   def reset(self, *args):
     return self.call('reset', args, cwd=self.dir)
 
-# Create build environment.
+  def pull(self, *args):
+    return self.call('pull', args, cwd=self.dir)
+
+  def update(self, *args):
+    if not os.path.exists(self.dir):
+      self.clone(*args)
+
+# Import the documentation build module.
 fmt_dir = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 sys.path.insert(0, os.path.join(fmt_dir, 'doc'))
+import build
 
-work_dir = tempfile.mkdtemp('fmt')
-try:
-  import build
-  # The virtualenv is stored in ~/.cache/fmt/virtualenv and reused to speed
-  # up builds.
-  build.create_build_env(os.path.join(
-    os.path.expanduser('~'), '.cache', 'fmt', 'virtualenv'))
+work_dir = 'build'
 
-  fmt_repo = Git(os.path.join(work_dir, 'fmt'))
-  fmt_repo.clone('git@github.com:fmtlib/fmt')
-  doc_repo = Git('fmtlib.github.io')
-  doc_repo.clone('git@github.com:fmtlib/fmtlib.github.io')
+# Virtualenv and repos are cached to speed up builds.
+build.create_build_env(os.path.join(work_dir, 'virtualenv'))
 
-  for version in ['1.0.0']:#, '1.1.0', '2.0.0', '3.0.0']:
-    fmt_repo.clean('-f', '-d')
-    fmt_repo.reset('--hard')
-    fmt_repo.checkout(version)
-    target_doc_dir = os.path.join(fmt_repo.dir, 'doc')
-    # Remove the old theme.
-    for entry in os.listdir(target_doc_dir):
-      path = os.path.join(target_doc_dir, entry)
-      if os.path.isdir(path):
-        shutil.rmtree(path)
-    # Copy the new theme.
-    for entry in ['_static', '_templates', 'basic-bootstrap', 'bootstrap',
-                  'conf.py', 'fmt.less']:
-      src = os.path.join(fmt_dir, 'doc', entry)
-      dst = os.path.join(target_doc_dir, entry)
-      copy = shutil.copytree if os.path.isdir(src) else shutil.copyfile
-      copy(src, dst)
-    # Rename index to contents.
-    contents = os.path.join(target_doc_dir, 'contents.rst')
-    if not os.path.exists(contents):
-      os.rename(os.path.join(target_doc_dir, 'index.rst'), contents)
-    # Fix issues in reference.rst.
-    reference = os.path.join(target_doc_dir, 'reference.rst')
-    if os.path.exists(reference):
-      with open(reference) as f:
-        data = f.read()
-      data = data.replace('std::ostream &', 'std::ostream&')
-      data = re.sub('doxygenfunction.. (bin|oct|hexu|hex)',
-                    r'doxygenfunction:: \1(int)', data)
-      with open(reference, 'w') as f:
-        f.write(data)
-    # Build the docs.
-    build.build_docs(version, doc_dir=target_doc_dir, include_dir=fmt_repo.dir,
-                     work_dir=work_dir)
-    # Create symlinks for older versions.
-    for link, target in {'index': 'contents', 'api': 'reference'}.items():
-      os.symlink(target + '.html', os.path.join('html', link) + '.html')
-    # Copy docs to the website.
-    version_doc_dir = os.path.join(doc_repo.dir, version)
-    shutil.rmtree(version_doc_dir)
-    shutil.move('html', version_doc_dir)
-    # TODO: update links in navbar
-    # TODO: remove doc repo
-except:
-  shutil.rmtree(work_dir)
+fmt_repo = Git(os.path.join(work_dir, 'fmt'))
+fmt_repo.update('git@github.com:fmtlib/fmt')
+
+doc_repo = Git(os.path.join(work_dir, 'fmtlib.github.io'))
+doc_repo.update('git@github.com:fmtlib/fmtlib.github.io')
+
+for version in ['1.0.0']:#, '1.1.0', '2.0.0', '3.0.0']:
+  fmt_repo.clean('-f', '-d')
+  fmt_repo.reset('--hard')
+  fmt_repo.checkout(version)
+  target_doc_dir = os.path.join(fmt_repo.dir, 'doc')
+  # Remove the old theme.
+  for entry in os.listdir(target_doc_dir):
+    path = os.path.join(target_doc_dir, entry)
+    if os.path.isdir(path):
+      shutil.rmtree(path)
+  # Copy the new theme.
+  for entry in ['_static', '_templates', 'basic-bootstrap', 'bootstrap',
+		'conf.py', 'fmt.less']:
+    src = os.path.join(fmt_dir, 'doc', entry)
+    dst = os.path.join(target_doc_dir, entry)
+    copy = shutil.copytree if os.path.isdir(src) else shutil.copyfile
+    copy(src, dst)
+  # TODO: update links in navbar
+  # Rename index to contents.
+  contents = os.path.join(target_doc_dir, 'contents.rst')
+  if not os.path.exists(contents):
+    os.rename(os.path.join(target_doc_dir, 'index.rst'), contents)
+  # Fix issues in reference.rst.
+  reference = os.path.join(target_doc_dir, 'reference.rst')
+  if os.path.exists(reference):
+    with open(reference) as f:
+      data = f.read()
+    data = data.replace('std::ostream &', 'std::ostream&')
+    data = re.sub(r'doxygenfunction.. (bin|oct|hexu|hex)',
+		  r'doxygenfunction:: \1(int)', data)
+    with open(reference, 'w') as f:
+      f.write(data)
+  # Build the docs.
+  html_dir = build.build_docs(version, doc_dir=target_doc_dir,
+			      include_dir=fmt_repo.dir, work_dir=work_dir)
+  # Create symlinks for older versions.
+  for link, target in {'index': 'contents', 'api': 'reference'}.items():
+    os.symlink(target + '.html', os.path.join(html_dir, link) + '.html')
+  # Copy docs to the website.
+  version_doc_dir = os.path.join(doc_repo.dir, version)
+  shutil.rmtree(version_doc_dir)
+  shutil.move(html_dir, version_doc_dir)