new file mode 100644
--- /dev/null
+++ b/layout/style/GenerateServoCSSPropList.py
@@ -0,0 +1,110 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import buildconfig
+import mozpack.path as mozpath
+import os
+import subprocess
+import string
+import sys
+
+SERVO_BASE = mozpath.join(buildconfig.topsrcdir, "servo")
+SERVO_PROP_BASE = mozpath.join(SERVO_BASE, "components", "style", "properties")
+
+
+def generate_data(output, template):
+    output.write("# THIS IS AN AUTOGENERATED FILE.  DO NOT EDIT\n\n")
+    output.write(subprocess.check_output([
+        sys.executable,
+        mozpath.join(SERVO_PROP_BASE, "build.py"),
+        "gecko", "geckolib", template
+    ], universal_newlines=True))
+
+    # Add all relevant files into the dependencies of the generated file.
+    DEP_EXTS = [".py", ".rs", ".zip"]
+    deps = set()
+    for path, dirs, files in os.walk(SERVO_PROP_BASE):
+        for file in files:
+            if os.path.splitext(file)[1] in DEP_EXTS:
+                deps.add(mozpath.join(path, file))
+    return deps
+
+
+def generate_header(output, data):
+    with open(data, "r") as f:
+        data = eval(f.read())
+
+    output.write("""/* THIS IS AN AUTOGENERATED FILE.  DO NOT EDIT */
+
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#define CSS_PROP_DOMPROP_PREFIXED(name_) \\
+  CSS_PROP_PUBLIC_OR_PRIVATE(Moz ## name_, name_)
+
+#ifndef CSS_PROP_LONGHAND
+#define CSS_PROP_LONGHAND(name_, id_, method_, flags_, pref_) /* nothing */
+#define DEFINED_CSS_PROP_LONGHAND
+#endif
+
+#ifndef CSS_PROP_SHORTHAND
+#define CSS_PROP_SHORTHAND(name_, id_, method_, flags_, pref_) /* nothing */
+#define DEFINED_CSS_PROP_SHORTHAND
+#endif
+
+#ifndef CSS_PROP_ALIAS
+#define CSS_PROP_ALIAS(name_, aliasid_, id_, method_, pref_) /* nothing */
+#define DEFINED_CSS_PROP_ALIAS
+#endif
+
+""")
+
+    MACRO_NAMES = {
+        "longhand": "CSS_PROP_LONGHAND",
+        "shorthand": "CSS_PROP_SHORTHAND",
+        "alias": "CSS_PROP_ALIAS",
+    }
+    for name, method, id, flags, pref, proptype in data:
+        is_internal = "CSS_PROPERTY_INTERNAL" in flags
+        pref = '"' + pref + '"'
+        if proptype == "alias":
+            params = [name, id[0], id[1], method, pref]
+        else:
+            if method == "CssFloat":
+                method = "CSS_PROP_PUBLIC_OR_PRIVATE(CssFloat, Float)"
+            elif method.startswith("Moz"):
+                method = "CSS_PROP_DOMPROP_PREFIXED({})".format(method[3:])
+            if flags:
+                flags = " | ".join(flags)
+            else:
+                flags = "0"
+            params = [name, id, method, flags, pref]
+
+        if is_internal:
+            output.write("#ifndef CSS_PROP_LIST_EXCLUDE_INTERNAL\n")
+        output.write("{}({})\n".format(MACRO_NAMES[proptype], ", ".join(params)))
+        if is_internal:
+            output.write("#endif\n")
+
+    output.write("""
+#ifdef DEFINED_CSS_PROP_ALIAS
+#undef CSS_PROP_ALIAS
+#undef DEFINED_CSS_PROP_ALIAS
+#endif
+
+#ifdef DEFINED_CSS_PROP_SHORTHAND
+#undef CSS_PROP_SHORTHAND
+#undef DEFINED_CSS_PROP_SHORTHAND
+#endif
+
+#ifdef DEFINED_CSS_PROP_LONGHAND
+#undef CSS_PROP_LONGHAND
+#undef DEFINED_CSS_PROP_LONGHAND
+#endif
+
+#undef CSS_PROP_DOMPROP_PREFIXED
+""")

new file mode 100644
--- /dev/null
+++ b/layout/style/ServoCSSPropList.mako.py
@@ -0,0 +1,87 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+<%!
+# nsCSSPropertyID of longhands and shorthands is ordered alphabetically
+# with vendor prefixes removed. Note that aliases use their alias name
+# as order key directly because they may be duplicate without prefix.
+def order_key(prop):
+    if prop.name.startswith("-"):
+        return prop.name[prop.name.find("-", 1) + 1:]
+    return prop.name
+
+# See bug 1454823 for situation of internal flag.
+def is_internal(prop):
+    # A property which is not controlled by pref and not enabled in
+    # content by default is an internal property.
+    if not prop.gecko_pref and not prop.enabled_in_content():
+        return True
+    # There are some special cases we may want to remove eventually.
+    OTHER_INTERNALS = [
+        "-moz-context-properties",
+        "-moz-control-character-visibility",
+        "-moz-window-opacity",
+        "-moz-window-transform",
+        "-moz-window-transform-origin",
+    ]
+    return prop.name in OTHER_INTERNALS
+
+def flags(prop):
+    result = []
+    if prop.explicitly_enabled_in_chrome():
+        result.append("CSS_PROPERTY_ENABLED_IN_UA_SHEETS_AND_CHROME")
+    elif prop.explicitly_enabled_in_ua_sheets():
+        result.append("CSS_PROPERTY_ENABLED_IN_UA_SHEETS")
+    if is_internal(prop):
+        result.append("CSS_PROPERTY_INTERNAL")
+    if prop.enabled_in == "":
+        result.append("CSS_PROPERTY_PARSE_INACCESSIBLE")
+    return ", ".join('"{}"'.format(flag) for flag in result)
+
+def pref(prop):
+    if prop.gecko_pref:
+        return '"' + prop.gecko_pref + '"'
+    return '""'
+%>
+
+[
+    % for prop in sorted(data.longhands, key=order_key):
+    (
+        "${prop.name}",
+        % if prop.name == "float":
+        "CssFloat",
+        % elif prop.name.startswith("-x-"):
+        "${prop.camel_case[1:]}",
+        % else:
+        "${prop.camel_case}",
+        % endif
+        "${prop.ident}",
+        [${flags(prop)}],
+        ${pref(prop)},
+        "longhand",
+    ),
+    % endfor
+
+    % for prop in sorted(data.shorthands, key=order_key):
+    (
+        "${prop.name}",
+        "${prop.camel_case}",
+        "${prop.ident}",
+        [${flags(prop)}],
+        ${pref(prop)},
+        "shorthand",
+    ),
+    % endfor
+
+    % for prop in sorted(data.all_aliases(), key=lambda x: x.name):
+    (
+        "${prop.name}",
+        "${prop.camel_case}",
+        ("${prop.ident}", "${prop.original.ident}"),
+        [],
+        ${pref(prop)},
+        "alias",
+    ),
+    % endfor
+]

--- a/layout/style/moz.build
+++ b/layout/style/moz.build
@@ -58,16 +58,17 @@ EXPORTS += [
     'nsStyleStructInlines.h',
     'nsStyleStructList.h',
     'nsStyleTransformMatrix.h',
     'nsStyleUtil.h',
     'nsTimingFunction.h',
 ]
 
 EXPORTS.mozilla += [
+    '!ServoCSSPropList.h',
     'AnimationCollection.h',
     'BindingStyleRule.h',
     'CachedInheritingStyles.h',
     'ComputedStyle.h',
     'ComputedStyleInlines.h',
     'CSSEnabledState.h',
     'DeclarationBlock.h',
     'DeclarationBlockInlines.h',
@@ -269,20 +270,38 @@ RESOURCE_FILES += [
 CONTENT_ACCESSIBLE_FILES += [
     'ImageDocument.css',
     'res/plaintext.css',
     'res/viewsource.css',
     'TopLevelImageDocument.css',
     'TopLevelVideoDocument.css',
 ]
 
+GENERATED_FILES += [
+    'ServoCSSPropList.h',
+    'ServoCSSPropList.py',
+]
+
+servo_props = GENERATED_FILES['ServoCSSPropList.h']
+servo_props.script = 'GenerateServoCSSPropList.py:generate_header'
+servo_props.inputs = [
+    '!ServoCSSPropList.py',
+]
+
+servo_props = GENERATED_FILES['ServoCSSPropList.py']
+servo_props.script = 'GenerateServoCSSPropList.py:generate_data'
+servo_props.inputs = [
+    'ServoCSSPropList.mako.py',
+]
+
 if CONFIG['COMPILE_ENVIRONMENT']:
     GENERATED_FILES += [
         'nsCSSPropsGenerated.inc',
     ]
+
     css_props = GENERATED_FILES['nsCSSPropsGenerated.inc']
     css_props.script = 'GenerateCSSPropsGenerated.py:generate'
     css_props.inputs = [
         'nsCSSPropsGenerated.inc.in',
         'PythonCSSProps.h',
     ]
 
     CONFIGURE_SUBST_FILES += [

--- a/layout/style/nsCSSProps.cpp
+++ b/layout/style/nsCSSProps.cpp
@@ -142,16 +142,104 @@ CreateStaticTable(const char* const aRaw
     nsAutoCString temp(aRawTable[index]);
     MOZ_ASSERT(-1 == temp.FindChar('_'),
                "underscore char in case insensitive name table");
   }
 #endif
   return table;
 }
 
+#ifdef DEBUG
+static void
+CheckServoCSSPropList()
+{
+  struct PropData {
+    nsCSSPropertyID mID;
+    uint32_t mFlags;
+    const char* mPref;
+  };
+  const PropData sGeckoProps[eCSSProperty_COUNT_with_aliases] = {
+#define CSS_PROP(name_, id_, method_, flags_, pref_, ...) \
+    { eCSSProperty_##id_, flags_, pref_ },
+#include "nsCSSPropList.h"
+#undef CSS_PROP
+
+#define CSS_PROP_SHORTHAND(name_, id_, method_, flags_, pref_) \
+    { eCSSProperty_##id_, flags_, pref_ },
+#include "nsCSSPropList.h"
+#undef CSS_PROP_SHORTHAND
+
+#define CSS_PROP_ALIAS(aliasname_, aliasid_, propid_, aliasmethod_, pref_) \
+    { eCSSPropertyAlias_##aliasid_, 0, pref_ },
+#include "nsCSSPropAliasList.h"
+#undef CSS_PROP_ALIAS
+  };
+  const PropData sServoProps[eCSSProperty_COUNT_with_aliases] = {
+#define CSS_PROP_LONGHAND(name_, id_, method_, flags_, pref_) \
+    { eCSSProperty_##id_, flags_, pref_ },
+#define CSS_PROP_SHORTHAND(name_, id_, method_, flags_, pref_) \
+    { eCSSProperty_##id_, flags_, pref_ },
+#define CSS_PROP_ALIAS(name_, aliasid_, id_, method_, pref_) \
+    { eCSSPropertyAlias_##aliasid_, 0, pref_ },
+#include "mozilla/ServoCSSPropList.h"
+#undef CSS_PROP_ALIAS
+#undef CSS_PROP_SHORTHAND
+#undef CSS_PROP_LONGHAND
+  };
+
+  const uint32_t kServoFlags =
+    CSS_PROPERTY_ENABLED_MASK | CSS_PROPERTY_INTERNAL |
+    CSS_PROPERTY_PARSE_INACCESSIBLE;
+  bool mismatch = false;
+  for (size_t i = 0; i < eCSSProperty_COUNT_with_aliases; i++) {
+    auto& geckoData = sGeckoProps[i];
+    auto& servoData = sServoProps[i];
+    const char* name = nsCSSProps::GetStringValue(geckoData.mID).get();
+    if (geckoData.mID != servoData.mID) {
+      printf_stderr("Order mismatches: gecko: %s, servo: %s\n",
+                    name, nsCSSProps::GetStringValue(servoData.mID).get());
+      mismatch = true;
+      continue;
+    }
+    if ((geckoData.mFlags & kServoFlags) != servoData.mFlags) {
+      printf_stderr("Enabled flags of %s mismatch\n", name);
+      mismatch = true;
+    }
+    if (strcmp(geckoData.mPref, servoData.mPref) != 0) {
+      printf_stderr("Pref of %s mismatches\n", name);
+      mismatch = true;
+    }
+  }
+
+  const nsCSSPropertyID sGeckoAliases[eCSSAliasCount] = {
+#define CSS_PROP_ALIAS(aliasname_, aliasid_, propid_, aliasmethod_, pref_) \
+    eCSSProperty_##propid_,
+#include "nsCSSPropAliasList.h"
+#undef CSS_PROP_ALIAS
+  };
+  const nsCSSPropertyID sServoAliases[eCSSAliasCount] = {
+#define CSS_PROP_ALIAS(aliasname_, aliasid_, propid_, aliasmethod_, pref_) \
+    eCSSProperty_##propid_,
+#include "mozilla/ServoCSSPropList.h"
+#undef CSS_PROP_ALIAS
+  };
+  for (size_t i = 0; i < eCSSAliasCount; i++) {
+    if (sGeckoAliases[i] == sServoAliases[i]) {
+      continue;
+    }
+    nsCSSPropertyID aliasid = nsCSSPropertyID(eCSSProperty_COUNT + i);
+    printf_stderr("Original property of alias %s mismatches\n",
+                  nsCSSProps::GetStringValue(aliasid).get());
+    mismatch = true;
+  }
+
+  MOZ_ASSERT(!mismatch);
+}
+#endif
+
 void
 nsCSSProps::AddRefTable(void)
 {
   if (0 == gPropertyTableRefCount++) {
     MOZ_ASSERT(!gPropertyTable, "pre existing array!");
     MOZ_ASSERT(!gFontDescTable, "pre existing array!");
     MOZ_ASSERT(!gCounterDescTable, "pre existing array!");
     MOZ_ASSERT(!gPropertyIDLNameTable, "pre existing array!");
@@ -166,16 +254,20 @@ nsCSSProps::AddRefTable(void)
     for (nsCSSPropertyID p = nsCSSPropertyID(0);
          size_t(p) < ArrayLength(kIDLNameTable);
          p = nsCSSPropertyID(p + 1)) {
       if (kIDLNameTable[p]) {
         gPropertyIDLNameTable->Put(nsDependentCString(kIDLNameTable[p]), p);
       }
     }
 
+#ifdef DEBUG
+    CheckServoCSSPropList();
+#endif
+
     static bool prefObserversInited = false;
     if (!prefObserversInited) {
       prefObserversInited = true;
 
       #define OBSERVE_PROP(pref_, id_)                                        \
         if (pref_[0]) {                                                       \
           Preferences::AddBoolVarCache(&gPropertyEnabled[id_],                \
                                        pref_);                                \

--- a/servo/components/style/properties/build.py
+++ b/servo/components/style/properties/build.py
@@ -16,17 +16,17 @@ from mako.lookup import TemplateLookup
 from mako.template import Template
 
 import data
 
 RE_PYTHON_ADDR = re.compile(r'<.+? object at 0x[0-9a-fA-F]+>')
 
 
 def main():
-    usage = "Usage: %s [ servo | gecko ] [ style-crate | html ]" % sys.argv[0]
+    usage = "Usage: %s [ servo | gecko ] [ style-crate | geckolib <template> | html ]" % sys.argv[0]
     if len(sys.argv) < 3:
         abort(usage)
     product = sys.argv[1]
     output = sys.argv[2]
 
     if product not in ["servo", "gecko"] or output not in ["style-crate", "geckolib", "html"]:
         abort(usage)
 
@@ -34,16 +34,22 @@ def main():
     template = os.path.join(BASE, "properties.mako.rs")
     rust = render(template, product=product, data=properties, __file__=template)
     if output == "style-crate":
         write(os.environ["OUT_DIR"], "properties.rs", rust)
         if product == "gecko":
             template = os.path.join(BASE, "gecko.mako.rs")
             rust = render(template, data=properties)
             write(os.environ["OUT_DIR"], "gecko_properties.rs", rust)
+    elif output == "geckolib":
+        if len(sys.argv) < 4:
+            abort(usage)
+        template = sys.argv[3]
+        header = render(template, data=properties)
+        sys.stdout.write(header)
     elif output == "html":
         write_html(properties)
 
 
 def abort(message):
     sys.stderr.write(message + b"\n")
     sys.exit(1)
 

--- a/servo/components/style/properties/data.py
+++ b/servo/components/style/properties/data.py
@@ -380,16 +380,17 @@ class Shorthand(object):
         return "nsCSSPropertyID::eCSSProperty_%s" % self.ident
 
 
 class Alias(object):
     def __init__(self, name, original, gecko_pref):
         self.name = name
         self.ident = to_rust_ident(name)
         self.camel_case = to_camel_case(self.ident)
+        self.original = original
         self.enabled_in = original.enabled_in
         self.servo_pref = original.servo_pref
         self.gecko_pref = gecko_pref
         self.allowed_in_page_rule = original.allowed_in_page_rule
         self.allowed_in_keyframe_block = original.allowed_in_keyframe_block
 
     def experimental(self, product):
         if product == "gecko":