diff --git a/vk-layer-introspect b/vk-layer-introspect
new file mode 100755
index 0000000..e64373e
--- /dev/null
+++ b/vk-layer-introspect
@@ -0,0 +1,399 @@
+#!/usr/bin/env python3
+#
+# Copyright (c) 2016 Google Inc.
+#
+# 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.
+
+import argparse
+import ctypes
+import json
+import os
+import platform
+import sys
+import xml.etree.ElementTree
+
+if platform.system() == "Windows":
+    VKAPI_DLL = ctypes.windll
+    VKAPI_FUNCTYPE = ctypes.WINFUNCTYPE
+else:
+    VKAPI_DLL = ctypes.cdll
+    VKAPI_FUNCTYPE = ctypes.CFUNCTYPE
+
+# Vulkan types
+
+VkInstance = ctypes.c_void_p
+VkPhysicalDevice = ctypes.c_void_p
+VkDevice = ctypes.c_void_p
+VkResult = ctypes.c_int
+
+
+class VkLayerProperties(ctypes.Structure):
+    _fields_ = [("c_layerName", ctypes.c_char * 256),
+                ("c_specVersion", ctypes.c_uint32),
+                ("c_implementationVersion", ctypes.c_uint32),
+                ("c_description", ctypes.c_char * 256)]
+
+    def layer_name(self):
+        return self.c_layerName.decode()
+
+    def spec_version(self):
+        return "%d.%d.%d" % (
+            self.c_specVersion >> 22,
+            (self.c_specVersion >> 12) & 0x3ff,
+            self.c_specVersion & 0xfff)
+
+    def implementation_version(self):
+        return str(self.c_implementationVersion)
+
+    def description(self):
+        return self.c_description.decode()
+
+    def __eq__(self, other):
+        return (self.c_layerName == other.c_layerName and
+                self.c_specVersion == other.c_specVersion and
+                self.c_implementationVersion == other.c_implementationVersion and
+                self.c_description == other.c_description)
+
+
+class VkExtensionProperties(ctypes.Structure):
+    _fields_ = [("c_extensionName", ctypes.c_char * 256),
+                ("c_specVersion", ctypes.c_uint32)]
+
+    def extension_name(self):
+        return self.c_extensionName.decode()
+
+    def spec_version(self):
+        return str(self.c_specVersion)
+
+# Vulkan commands
+
+PFN_vkVoidFunction = VKAPI_FUNCTYPE(None)
+PFN_vkEnumerateInstanceExtensionProperties = VKAPI_FUNCTYPE(
+    VkResult, ctypes.c_char_p, ctypes.POINTER(ctypes.c_uint32), ctypes.POINTER(VkExtensionProperties))
+PFN_vkEnumerateDeviceExtensionProperties = VKAPI_FUNCTYPE(
+    VkResult, VkPhysicalDevice, ctypes.c_char_p, ctypes.POINTER(ctypes.c_uint32), ctypes.POINTER(VkExtensionProperties))
+PFN_vkEnumerateInstanceLayerProperties = VKAPI_FUNCTYPE(
+    VkResult, ctypes.POINTER(ctypes.c_uint32), ctypes.POINTER(VkLayerProperties))
+PFN_vkEnumerateDeviceLayerProperties = VKAPI_FUNCTYPE(
+    VkResult, VkPhysicalDevice, ctypes.POINTER(ctypes.c_uint32), ctypes.POINTER(VkLayerProperties))
+PFN_vkGetInstanceProcAddr = VKAPI_FUNCTYPE(
+    PFN_vkVoidFunction, VkInstance, ctypes.c_char_p)
+PFN_vkGetDeviceProcAddr = VKAPI_FUNCTYPE(
+    PFN_vkVoidFunction, VkDevice, ctypes.c_char_p)
+
+
+class Layer(object):
+
+    def __init__(self, *args):
+        self.props = args[0]
+        self.is_global = args[1]
+        self.instance_extensions = args[2]
+        self.device_extensions = args[3]
+        self.gipa_name = args[4]
+        self.gdpa_name = args[5]
+
+
+class LayerLibrary(object):
+
+    def __init__(self, path):
+        self.library = None
+        self.version = 0
+
+        self._load(path)
+        self._negotiate_version()
+
+    def introspect(self):
+        if self.version == 0:
+            layers = self._enumerate_layers_v0()
+        else:
+            raise RuntimeError("unsupported v%d library" % self.version)
+
+        return layers
+
+    def _load(self, path):
+        try:
+            abspath = os.path.abspath(path)
+            self.library = VKAPI_DLL.LoadLibrary(abspath)
+        except OSError:
+            raise RuntimeError("failed to load library")
+
+    def _unload(self):
+        # no clean way to unload
+        pass
+
+    def _negotiate_version(self):
+        # only v0
+        self.version = 0
+
+    def _enumerate_properties_errcheck_v0(self, result, func, args):
+        if isinstance(func, PFN_vkEnumerateInstanceLayerProperties):
+            func_name = "vkEnumerateInstanceLayerProperties"
+        elif isinstance(func, PFN_vkEnumerateDeviceLayerProperties):
+            func_name = "vkEnumerateDeviceLayerProperties"
+        elif isinstance(func, PFN_vkEnumerateInstanceExtensionProperties):
+            func_name = "vkEnumerateInstanceExtensionProperties"
+        elif isinstance(func, PFN_vkEnumerateDeviceExtensionProperties):
+            func_name = "vkEnumerateDeviceExtensionProperties"
+        else:
+            raise AssertionError("unexpected vkEnumerate*Properties call")
+
+        if result != 0:
+            raise RuntimeError(func_name + " failed with " + str(result))
+
+        # pProperties and pCount mismatch
+        if args[-1] and len(args[-1]) != args[-2].value:
+            raise RuntimeError("invalid pCount returned in " + func_name)
+
+        return args[-1]
+
+    def _enumerate_properties_prototype_v0(self, func_name):
+        prototypes = {
+            "vkEnumerateInstanceLayerProperties":
+            PFN_vkEnumerateInstanceLayerProperties,
+            "vkEnumerateDeviceLayerProperties":
+            PFN_vkEnumerateDeviceLayerProperties,
+            "vkEnumerateInstanceExtensionProperties":
+            PFN_vkEnumerateInstanceExtensionProperties,
+            "vkEnumerateDeviceExtensionProperties":
+            PFN_vkEnumerateDeviceExtensionProperties,
+        }
+        prototype = prototypes[func_name]
+
+        try:
+            proc = prototype((func_name, self.library))
+        except AttributeError:
+            raise RuntimeError(func_name + " is missing")
+
+        proc.errcheck = self._enumerate_properties_errcheck_v0
+
+        return proc
+
+    def _get_gipa_name_v0(self, layer_name, can_fallback):
+        names = [layer_name + "GetInstanceProcAddr"]
+        if can_fallback:
+            names.append("vkGetInstanceProcAddr")
+
+        for name in names:
+            try:
+                PFN_vkGetInstanceProcAddr((name, self.library))
+                return name
+            except AttributeError:
+                pass
+
+        raise RuntimeError(" or ".join(names) + " is missing")
+
+    def _get_gdpa_name_v0(self, layer_name, can_fallback):
+        names = [layer_name + "GetDeviceProcAddr"]
+        if can_fallback:
+            names.append("vkGetDeviceProcAddr")
+
+        for name in names:
+            try:
+                PFN_vkGetDeviceProcAddr((name, self.library))
+                return name
+            except AttributeError:
+                pass
+
+        raise RuntimeError(" or ".join(names) + " is missing")
+
+    def _enumerate_layers_v0(self):
+        tmp_count = ctypes.c_uint32()
+
+        # enumerate instance layers
+        enumerate_instance_layer_properties = self._enumerate_properties_prototype_v0(
+            "vkEnumerateInstanceLayerProperties")
+        enumerate_instance_layer_properties(tmp_count, None)
+        p_props = enumerate_instance_layer_properties(
+            tmp_count, (VkLayerProperties * tmp_count.value)())
+
+        # enumerate device layers
+        enumerate_device_layer_properties = self._enumerate_properties_prototype_v0(
+            "vkEnumerateDeviceLayerProperties")
+        enumerate_device_layer_properties(None, tmp_count, None)
+        dev_p_props = enumerate_device_layer_properties(
+            None, tmp_count, (VkLayerProperties * tmp_count.value)())
+
+        # there must not be device-only layers
+        for props in dev_p_props:
+            if props not in p_props:
+                raise RuntimeError(
+                    "unexpected device-only layer " + props.layer_name())
+
+        layers = []
+        for props in p_props:
+            is_global = (props in dev_p_props)
+
+            # enumerate instance extensions
+            enumerate_instance_extension_properties = self._enumerate_properties_prototype_v0(
+                "vkEnumerateInstanceExtensionProperties")
+            enumerate_instance_extension_properties(
+                props.c_layerName, tmp_count, None)
+            instance_extensions = enumerate_instance_extension_properties(
+                props.c_layerName,
+                tmp_count,
+                (VkExtensionProperties * tmp_count.value)())
+
+            gipa_name = self._get_gipa_name_v0(
+                props.layer_name(),
+                len(p_props) == 1)
+
+            if is_global:
+                # enumerate device extensions
+                enumerate_device_extension_properties = self._enumerate_properties_prototype_v0(
+                    "vkEnumerateDeviceExtensionProperties")
+                enumerate_device_extension_properties(
+                    None, props.c_layerName, tmp_count, None)
+                device_extensions = enumerate_device_extension_properties(
+                    None,
+                    props.c_layerName,
+                    tmp_count,
+                    (VkExtensionProperties * tmp_count.value)())
+
+                gdpa_name = self._get_gdpa_name_v0(
+                    props.layer_name(),
+                    len(p_props) == 1)
+            else:
+                device_extensions = None
+                gdpa_name = None
+
+            layers.append(
+                Layer(props, is_global, instance_extensions, device_extensions, gipa_name, gdpa_name))
+
+        return layers
+
+
+def serialize_layers(layers, path, ext_cmds):
+    data = {}
+    data["file_format_version"] = '1.0.0'
+
+    for idx, layer in enumerate(layers):
+        layer_data = {}
+
+        layer_data["name"] = layer.props.layer_name()
+        layer_data["api_version"] = layer.props.spec_version()
+        layer_data[
+            "implementation_version"] = layer.props.implementation_version()
+        layer_data["description"] = layer.props.description()
+
+        layer_data["type"] = "GLOBAL" if layer.is_global else "INSTANCE"
+
+        # TODO more flexible
+        layer_data["library_path"] = os.path.join(".", os.path.basename(path))
+
+        funcs = {}
+        if layer.gipa_name != "vkGetInstanceProcAddr":
+            funcs["vkGetInstanceProcAddr"] = layer.gipa_name
+        if layer.is_global and layer.gdpa_name != "vkGetDeviceProcAddr":
+            funcs["vkGetDeviceProcAddr"] = layer.gdpa_name
+        if funcs:
+            layer_data["functions"] = funcs
+
+        if layer.instance_extensions:
+            exts = [{
+                "name": ext.extension_name(),
+                "spec_version": ext.spec_version(),
+            } for ext in layer.instance_extensions]
+            layer_data["instance_extensions"] = exts
+
+        if layer.device_extensions:
+            exts = []
+            for ext in layer.device_extensions:
+                try:
+                    cmds = ext_cmds[ext.extension_name()]
+                except KeyError:
+                    raise RuntimeError(
+                        "unknown device extension " + ext.extension_name())
+                else:
+                    ext_data = {}
+                    ext_data["name"] = ext.extension_name()
+                    ext_data["spec_version"] = ext.spec_version()
+                    if cmds:
+                        ext_data["entrypoints"] = cmds
+
+                    exts.append(ext_data)
+
+            layer_data["device_extensions"] = exts
+
+        if idx > 0:
+            data["layer.%d" % idx] = layer_data
+        else:
+            data["layer"] = layer_data
+
+    return data
+
+
+def dump_json(data):
+    dump = json.dumps(data, indent=4, sort_keys=True)
+
+    # replace "layer.<idx>" by "layer"
+    lines = dump.split("\n")
+    for line in lines:
+        if line.startswith("    \"layer.") and line.endswith("\": {"):
+            line = "    \"layer\": {"
+        print(line)
+
+
+def parse_vk_xml(path):
+    """Parse vk.xml to get commands added by extensions."""
+    tree = xml.etree.ElementTree.parse(path)
+    extensions = tree.find("extensions")
+
+    ext_cmds = {}
+    for ext in extensions.iter("extension"):
+        if ext.attrib["supported"] != "vulkan":
+            continue
+
+        cmds = []
+        for cmd in ext.iter("command"):
+            cmds.append(cmd.attrib["name"])
+
+        ext_cmds[ext.attrib["name"]] = cmds
+
+    return ext_cmds
+
+
+def add_custom_ext_cmds(ext_cmds):
+    """Add commands added by in-development extensions."""
+    # VK_LAYER_LUNARG_basic
+    ext_cmds["vkLayerBasicEXT"] = ["vkLayerBasicEXT"]
+
+
+def main():
+    default_vk_xml = sys.path[0] + "/vk.xml" if sys.path[0] else "vk.xml"
+
+    parser = argparse.ArgumentParser(description="Introspect a layer library.")
+    parser.add_argument(
+        "-x", dest="vk_xml", default=default_vk_xml, help="Path to vk.xml")
+    parser.add_argument(
+        "layer_libs", metavar="layer-lib", nargs="+", help="Path to a layer library")
+    args = parser.parse_args()
+
+    try:
+        ext_cmds = parse_vk_xml(args.vk_xml)
+    except Exception as e:
+        print("failed to parse %s: %s" % (args.vk_xml, e))
+        sys.exit(-1)
+
+    add_custom_ext_cmds(ext_cmds)
+
+    for path in args.layer_libs:
+        try:
+            ll = LayerLibrary(path)
+            layers = ll.introspect()
+            data = serialize_layers(layers, path, ext_cmds)
+            dump_json(data)
+        except RuntimeError as err:
+            print("skipping %s: %s" % (path, err))
+
+if __name__ == "__main__":
+    main()