diff --git a/ecdsa/_version.py b/ecdsa/_version.py
index 0a64833f..598f1542 100644
--- a/ecdsa/_version.py
+++ b/ecdsa/_version.py
@@ -6,7 +6,7 @@
 # that just contains the computed version number.
 
 # This file is released into the public domain. Generated by
-# versioneer-0.11 (https://github.com/warner/python-versioneer)
+# versioneer-0.12 (https://github.com/warner/python-versioneer)
 
 # these strings will be replaced by git during git-archive
 git_refnames = "$Format:%d$"
diff --git a/versioneer.py b/versioneer.py
index 03193e88..481180d8 100644
--- a/versioneer.py
+++ b/versioneer.py
@@ -1,5 +1,5 @@
 
-# Version: 0.11
+# Version: 0.12
 
 """
 The Versioneer
@@ -88,12 +88,20 @@
 
   A project-relative pathname into which the generated version strings should
   be written. This is usually a `_version.py` next to your project's main
-  `__init__.py` file. If your project uses `src/myproject/__init__.py`, this
-  should be `src/myproject/_version.py`. This file should be checked in to
-  your VCS as usual: the copy created below by `setup.py versioneer` will
-  include code that parses expanded VCS keywords in generated tarballs. The
-  'build' and 'sdist' commands will replace it with a copy that has just the
-  calculated version string.
+  `__init__.py` file, so it can be imported at runtime. If your project uses
+  `src/myproject/__init__.py`, this should be `src/myproject/_version.py`.
+  This file should be checked in to your VCS as usual: the copy created below
+  by `setup.py versioneer` will include code that parses expanded VCS
+  keywords in generated tarballs. The 'build' and 'sdist' commands will
+  replace it with a copy that has just the calculated version string.
+
+  This must be set even if your project does not have any modules (and will
+  therefore never import `_version.py`), since "setup.py sdist" -based trees
+  still need somewhere to record the pre-calculated version strings. Anywhere
+  in the source tree should do. If there is a `__init__.py` next to your
+  `_version.py`, the `setup.py versioneer` command (described below) will
+  append some `__version__`-setting assignments, if they aren't already
+  present.
 
 *  `versionfile_build`:
 
@@ -103,6 +111,13 @@
   then you will probably have `versionfile_build='myproject/_version.py'` and
   `versionfile_source='src/myproject/_version.py'`.
 
+  If this is set to None, then `setup.py build` will not attempt to rewrite
+  any `_version.py` in the built tree. If your project does not have any
+  libraries (e.g. if it only builds a script), then you should use
+  `versionfile_build = None` and override `distutils.command.build_scripts`
+  to explicitly insert a copy of `versioneer.get_version()` into your
+  generated script.
+
 * `tag_prefix`:
 
   a string, like 'PROJECTNAME-', which appears at the start of all VCS tags.
@@ -139,11 +154,11 @@
         version=versioneer.get_version(),
         cmdclass=versioneer.get_cmdclass(),
 
-* 4: now run `setup.py versioneer`, which will create `_version.py`, and
-  will modify your `__init__.py` to define `__version__` (by calling a
-  function from `_version.py`). It will also modify your `MANIFEST.in` to
-  include both `versioneer.py` and the generated `_version.py` in sdist
-  tarballs.
+* 4: now run `setup.py versioneer`, which will create `_version.py`, and will
+  modify your `__init__.py` (if one exists next to `_version.py`) to define
+  `__version__` (by calling a function from `_version.py`). It will also
+  modify your `MANIFEST.in` to include both `versioneer.py` and the generated
+  `_version.py` in sdist tarballs.
 
 * 5: commit these changes to your VCS. To make sure you won't forget,
   `setup.py versioneer` will mark everything it touched for addition.
@@ -210,7 +225,7 @@
 `__init__.py` to place a basic version in `YOURPROJECT.__version__`:
 
     from ._version import get_versions
-    __version = get_versions()['version']
+    __version__ = get_versions()['version']
     del get_versions
 
 ## Updating Versioneer
@@ -231,6 +246,10 @@
 `setup.py versioneer`. This will enable the use of additional version-control
 systems (SVN, etc) in the future.
 
+### Upgrading from 0.11 to 0.12
+
+Nothing special.
+
 ## Future Directions
 
 This tool is designed to make it easily extended to other version-control
@@ -308,7 +327,7 @@ def run_command(commands, args, cwd=None, verbose=False, hide_stderr=False):
 # that just contains the computed version number.
 
 # This file is released into the public domain. Generated by
-# versioneer-0.11 (https://github.com/warner/python-versioneer)
+# versioneer-0.12 (https://github.com/warner/python-versioneer)
 
 # these strings will be replaced by git during git-archive
 git_refnames = "%(DOLLAR)sFormat:%%d%(DOLLAR)s"
@@ -584,7 +603,9 @@ def do_vcs_install(manifest_in, versionfile_source, ipy):
     GITS = ["git"]
     if sys.platform == "win32":
         GITS = ["git.cmd", "git.exe"]
-    files = [manifest_in, versionfile_source, ipy]
+    files = [manifest_in, versionfile_source]
+    if ipy:
+        files.append(ipy)
     try:
         me = __file__
         if me.endswith(".pyc") or me.endswith(".pyo"):
@@ -602,7 +623,7 @@ def do_vcs_install(manifest_in, versionfile_source, ipy):
                     present = True
         f.close()
     except EnvironmentError:
-        pass    
+        pass
     if not present:
         f = open(".gitattributes", "a+")
         f.write("%s export-subst\n" % versionfile_source)
@@ -622,7 +643,7 @@ def versions_from_parentdir(parentdir_prefix, root, verbose=False):
     return {"version": dirname[len(parentdir_prefix):], "full": ""}
 
 SHORT_VERSION_PY = """
-# This file was generated by 'versioneer.py' (0.11) from
+# This file was generated by 'versioneer.py' (0.12) from
 # revision-control system data, or from the parent directory name of an
 # unpacked source archive. Distribution tarballs contain a pre-generated copy
 # of this file.
@@ -740,11 +761,12 @@ def run(self):
         _build.run(self)
         # now locate _version.py in the new build/ directory and replace it
         # with an updated value
-        target_versionfile = os.path.join(self.build_lib, versionfile_build)
-        print("UPDATING %s" % target_versionfile)
-        os.unlink(target_versionfile)
-        with open(target_versionfile, "w") as f:
-            f.write(SHORT_VERSION_PY % versions)
+        if versionfile_build:
+            target_versionfile = os.path.join(self.build_lib, versionfile_build)
+            print("UPDATING %s" % target_versionfile)
+            os.unlink(target_versionfile)
+            with open(target_versionfile, "w") as f:
+                f.write(SHORT_VERSION_PY % versions)
 
 if 'cx_Freeze' in sys.modules:  # cx_freeze enabled?
     from cx_Freeze.dist import build_exe as _build_exe
@@ -813,17 +835,21 @@ def run(self):
                             })
 
         ipy = os.path.join(os.path.dirname(versionfile_source), "__init__.py")
-        try:
-            with open(ipy, "r") as f:
-                old = f.read()
-        except EnvironmentError:
-            old = ""
-        if INIT_PY_SNIPPET not in old:
-            print(" appending to %s" % ipy)
-            with open(ipy, "a") as f:
-                f.write(INIT_PY_SNIPPET)
+        if os.path.exists(ipy):
+            try:
+                with open(ipy, "r") as f:
+                    old = f.read()
+            except EnvironmentError:
+                old = ""
+            if INIT_PY_SNIPPET not in old:
+                print(" appending to %s" % ipy)
+                with open(ipy, "a") as f:
+                    f.write(INIT_PY_SNIPPET)
+            else:
+                print(" %s unmodified" % ipy)
         else:
-            print(" %s unmodified" % ipy)
+            print(" %s doesn't exist, ok" % ipy)
+            ipy = None
 
         # Make sure both the top-level "versioneer.py" and versionfile_source
         # (PKG/_version.py, used by runtime code) are in MANIFEST.in, so