diff --git a/specs/README.md b/specs/README.md
index 2501e6a4ebb..95bd287f2fb 100644
--- a/specs/README.md
+++ b/specs/README.md
@@ -1,37 +1,2 @@
-The Sky Environment
-===================
-
-The main files loaded by the Sky environment are Sky files, though
-they can refer to binary resources like images and fonts.
-
-Sky files
----------
-
-Conventional MIME type: ``text/sky``, though this type is neither
-necessary nor sufficient to indicate that a file is a Sky file; only
-the signature matters for type dispatch of Sky files.
-
-Conventional extension: ``.sky``
-
-Signatures:
-
-For application files, one of the following:
-* ``23 21 6d 6f 6a 6f 20 6d 6f 6a 6f 3a 73 6b 79 0a`` ("``#!mojo mojo:sky\n``")
-* ``23 21 6d 6f 6a 6f 20 6d 6f 6a 6f 3a 73 6b 79 0d`` ("``#!mojo mojo:sky\r``")
-* ``23 21 6d 6f 6a 6f 20 6d 6f 6a 6f 3a 73 6b 79 20`` ("``#!mojo mojo:sky ``")
-
-For module files, one of the following:
-* ``53 4b 59 20 4d 4f 44 55 4c 45 0a`` ("``SKY MODULE\n``")
-* ``53 4b 59 20 4d 4f 44 55 4c 45 0d`` ("``SKY MODULE\r``")
-* ``53 4b 59 20 4d 4f 44 55 4c 45 20`` ("``SKY MODULE ``")
-
-
-Notes
------
-
-```
-magical imports:
-  the mojo fabric API   dart:mojo
-  the mojom for the shell, proxying through C++ so that the shell pipe isn't exposed  dart:mojo-shell
-  the Sky API  dart:sky
-```
+This file contains documentation for what we hope Sky to support in due course.
+It's mostly proposals. It's not intended to be comprehensive.
diff --git a/specs/animation.md b/specs/animation.md
deleted file mode 100644
index 06f72e6f802..00000000000
--- a/specs/animation.md
+++ /dev/null
@@ -1,58 +0,0 @@
-Animation API
-=============
-
-```dart
-typedef void TimerCallback();
-
-external void _addTask({ TimerCallback callback, Duration budget, int bits, int priority, Queue queue });
-// see (runloop.md)[runloop.md] for the semantics of tasks and queues
-// _addTask() does the zone magic on callback
-
-external final Queue get _idleQueue;
-external final Queue get _paintQueue;
-external final Queue get _nextPaintQueue;
-
-class AnimationTimer extends Timer {
-  factory whenIdle(TimerCallback callback, { Duration budget: 1.0 }) {
-    if (budget.inMilliseconds > 1.0)
-      budget = new Duration(milliseconds: 1.0);
-    _addTask(callback: callback, budget: budget, bits: IdleTask, priority: IdlePriority, queue: _idleQueue);
-  }
-
-  factory beforePaint(TimerCallback callback, { int priority: 0 }) {
-    _addTask(callback: callback, budget: new Duration(milliseconds: 1.0), bits: PaintTask, priority: priority, queue: _paintQueue);
-  }
-
-  factory nextFrame(TimerCallback callback, { int priority: 0 }) {
-    _addTask(callback: callback, budget: new Duration(milliseconds: 1.0), bits: PaintTask, priority: priority, queue: _nextPaintQueue);
-  }
-}
-```
-
-
-Easing Functions
-----------------
-
-```dart
-// part of the framework, not dart:sky
-
-typedef void AnimationCallback();
-
-abstract class EasingFunction {
-  EasingFunction({double duration: 0.0, AnimationCallback completionCallback: null });
-  double getFactor(Float time);
-  // calls completionCallback if time >= duration
-  // then returns a number ostensibly in the range 0.0 to 1.0
-  // (but it could in practice go outside this range, e.g. for
-  // animation styles that overreach then come back)
-}
-```
-
-If you want to have two animations simultaneously, e.g. two
-transforms, then you can add to the RenderNode's overrideStyles a
-StyleValue that combines other StyleValues, e.g. a
-"TransformStyleValueCombinerStyleValue", and then add to it the
-regular animated StyleValues, e.g. multiple
-"AnimatedTransformStyleValue" objects. A framework API could make
-setting all that up easy, given the right underlying StyleValue
-classes.
diff --git a/specs/builtins.md b/specs/builtins.md
deleted file mode 100644
index 90ac3dbc3f5..00000000000
--- a/specs/builtins.md
+++ /dev/null
@@ -1,112 +0,0 @@
-Built-In Elements
-=================
-
-```dart
-SKY MODULE
-
-<script>
-import 'dart:sky';
-
-class ImportElement extends Element {
-  ImportElement = Element;
-
-  @override
-  Type getLayoutManager() => null; // O(1)
-}
-
-class TemplateElement extends Element {
-  TemplateElement = Element;
-
-  // TODO(ianh): convert <template> to using a token stream instead of a Fragment
-
-  external Fragment get content; // O(1)
-
-  @override
-  Type getLayoutManager() => null; // O(1)
-}
-
-class ScriptElement extends Element {
-  ScriptElement = Element;
-
-  @override
-  Type getLayoutManager() => null; // O(1)
-}
-
-class StyleElement extends Element {
-  StyleElement = Element;
-
-  external List<Rule> getRules(); // O(N) in rules
-
-  @override
-  Type getLayoutManager() => null; // O(1)
-}
-
-class ContentElement extends Element {
-  ContentElement = Element;
-
-  external List<Node> getDistributedNodes(); // O(N) in distributed nodes
-
-  @override
-  Type getLayoutManager() => null; // O(1)
-}
-
-class ImgElement extends Element {
-  ImgElement = Element;
-
-  @override
-  Type getLayoutManager() => ImgElementLayoutManager; // O(1)
-}
-
-class DivElement extends Element {
-  DivElement = Element;
-}
-
-class SpanElement extends Element {
-  SpanElement = Element;
-}
-
-class IframeElement extends Element {
-  IframeElement = Element;
-
-  @override
-  Type getLayoutManager() => IframeElementLayoutManager; // O(1)
-}
-
-class TElement extends Element {
-  TElement = Element;
-}
-
-class AElement extends Element {
-  AElement = Element;
-}
-
-class TitleElement extends Element {
-  TitleElement = Element;
-
-  @override
-  Type getLayoutManager() => null; // O(1)
-}
-
-class _ErrorElement extends Element {
-  _ErrorElement._create();
-
-  @override
-  Type getLayoutManager() => _ErrorElementLayoutManager; // O(1)
-}
-
-void _init(script) {
-  module.registerElement('import', ImportElement);
-  module.registerElement('template', TemplateElement);
-  module.registerElement('script', ScriptElement);
-  module.registerElement('style', StyleElement);
-  module.registerElement('content', ContentElement);
-  module.registerElement('img', ImgElement);
-  module.registerElement('div', DivElement);
-  module.registerElement('span', SpanElement);
-  module.registerElement('iframe', IframeElement);
-  module.registerElement('t', TElement);
-  module.registerElement('a', AElement);
-  module.registerElement('title', TitleElement);
-}
-</script>
-```
diff --git a/specs/conventions.md b/specs/conventions.md
deleted file mode 100644
index 25c24e277d9..00000000000
--- a/specs/conventions.md
+++ /dev/null
@@ -1,6 +0,0 @@
-Best Practices and Conventions for Sky Frameworks
-=================================================
-
-* elements should not expose convenience property accessors that just
-  reflect content attributes.
-
diff --git a/specs/elements.md b/specs/elements.md
deleted file mode 100644
index 99bd845dd8b..00000000000
--- a/specs/elements.md
+++ /dev/null
@@ -1,288 +0,0 @@
-Sky DOM APIs
-============
-
-```dart
-// ELEMENT TREE API
-
-abstract class Node extends EventTarget {
-  @override
-  external List<EventTarget> getEventDispatchChain(); // O(N) in number of ancestors across shadow trees
-  // implements EventTarget.getEventDispatchChain()
-  // returns the event dispatch chain (including handling shadow trees)
-
-  external Root get owner; // O(1)
-
-  external ParentNode get parentNode; // O(1)
-  Element get parentElement {
-    if (parentNode is Element)
-      return parentNode as Element;
-    return null;
-  }
-
-  external Node get previousSibling; // O(1)
-  Element get previousElementSibling {
-    var result = previousSibling;
-    while (result != null && result is! Element)
-      result = result.previousSibling;
-    return result as Element;
-  }
-
-  external Node get nextSibling; // O(1)
-  Element get nextElementSibling {
-    var result = nextSibling;
-    while (result != null && result is! Element)
-      result = result.nextSibling;
-    return result as Element;
-  }
-
-  // TODO(ianh): rename insertBefore() and insertAfter() since the Web
-  // has an insertBefore() that means something else. What's a good
-  // name, though?
-
-  external void _insertBefore(Node node); // O(N) in number of descendants
-  // node must be Text or Element, parentNode must be non-null
-  void insertBefore(List nodes) {
-    List.forEach((node) {
-      if (node is String)
-        node = new Text(node);
-      _insertBefore(node);
-    });    
-  }
-
-  external void _insertAfter(Node node); // O(N) in number of arguments plus all their descendants
-  // node must be Text or Element, parentNode must be non-null
-  void insertAfter(List nodes) {
-    var lastNode = this;
-    List.forEach((node) {
-      if (node is String)
-        node = new Text(node);
-      lastNode._insertAfter(node);
-      lastNode = node;
-    });
-  }
-
-  void replaceWith(List nodes) {
-    if (nextSibling != null) {
-      var anchor = nextSibling;
-      remove(); // parentNode can't be null here, so this won't throw
-      anchor.insertBefore(nodes);
-    } else {
-      var anchor = parentNode;
-      remove(); // throws if parentNode is null
-      anchor.append(nodes);
-    }
-  }
-
-  external void remove(); // O(N) in number of descendants
-  // parentNode must be non-null
-
-  // called when parentNode changes
-  // this is why insertBefore(), append(), et al, are O(N) -- the whole affected subtree is walked
-  // mutating the element tree from within this is strongly discouraged, since it will result in the
-  // callbacks being invoked while the element tree is in a different state than implied by the callbacks
-  external void parentChangedCallback(ParentNode oldParent, ParentNode newParent); // O(N) in descendants
-  // default implementation calls attached/detached
-  void attachedCallback() { }
-  void detachedCallback() { }
-
-  external List<ContentElement> getDestinationInsertionPoints(); // O(N) in number of insertion points the node is in
-  // returns the <content> elements to which this element was distributed
-
-  external Node cloneNode({bool deep: false}); // O(1) if deep=false, O(N) in the number of descendants if deep=true
-
-  external ElementStyleDeclarationList get style; // O(1)
-  // for nodes that aren't in the ApplicationRoot's composed tree,
-  // returns null (so in particular orphaned subtrees and nodes in
-  // module Roots don't have one, nor do shadow tree Roots)
-  // also always returns null for ContentElement elements
-  //  -- should be (lazily) updated when the node's parent chain
-  //     changes (same time as, e.g., the id hashtable is marked
-  //     dirty)
-
-  external RenderNode get renderNode; // O(1)
-  // this will be null until the first time it is rendered
-  // it becomes null again when it is taken out of the rendering (see style.md)
-
-  Type getLayoutManager() => null; // O(1)
-
-  void resetLayoutManager() { // O(1)
-    if (renderNode != null) {
-      renderNode._layoutManager = null;
-      renderNode._needsManager = true;
-    }
-  }
-}
-
-abstract class ParentNode extends Node {
-  external Node get firstChild; // O(1)
-  Element get firstElementChild {
-    var result = firstChild;
-    while (result != null && result is! Element)
-      result = result.nextSibling;
-    return result as Element;
-  }
-
-  external Node get lastChild; // O(1)
-  Element get lastElementChild {
-    var result = lastChild;
-    while (result != null && result is! Element)
-      result = result.previousSibling;
-    return result as Element;
-  }
-
-  // Returns a new List every time.
-  external List<Node> getChildren(); // O(N) in number of child nodes
-  List<Element> getChildElements() {
-    // that the following works without a cast is absurd
-    return getChildren().where((node) => node is Element).toList();
-  }
-
-  external void _appendChild(Node node); // O(N) in number of descendants
-  // node must be Text or Element
-  void appendChild(node) {
-    if (node is String)
-      node = new Text(node);
-    _appendChild(node);
-  }
-  void append(List nodes) {
-    nodes.forEach(appendChild);
-  }
-
-  external void _prependChild(Node node); // O(N) in number of descendants
-  // node must be Text or Element
-  void prependChild(node) {
-    if (node is String)
-      node = new Text(node);
-    _prependChild(node);
-  }
-  void prepend(List nodes) {
-    // note: not implemented in terms of _prependChild()
-    if (firstChild != null)
-      firstChild.insertBefore(nodes);
-    else
-      append(nodes);
-  }
-
-  external void removeChildren(); // O(N) in number of descendants
-  void setChild(node) {
-    removeChildren();
-    appendChild(node);
-  }
-  void setChildren(List nodes) {
-    removeChildren();
-    append(nodes);
-  }
-}
-
-class Attr {
-  const Attr (this.name, [this.value = '']); // O(1)
-  final String name; // O(1)
-  final String value; // O(1)
-}
-
-// @hasShadow annotation for registering elements
-class _HasShadow {
-  const _HasShadow();
-}
-const hasShadow = const _HasShadow();
-
-abstract class Element extends ParentNode {
-  Element({Map<String, String> attributes: null,
-           List children: null,
-           Module hostModule: null}) { // O(M+N), M = number of attributes, N = number of children nodes plus all their descendants
-    var shadowClass = reflectClass(hasShadow.runtimeType);
-    var shadowAnnotations = reflect(this).type.metadata.where((mirror) => mirror.type == shadowClass);
-    if (shadowAnnotations.length > 2)
-      throw new StateError('@hasShadow specified multiple times on ' + currentMirrorSystem().getName(reflectClass(this.runtimeType).simpleName));
-    bool needsShadow = shadowAnnotations.length == 1;
-    if (children != null)
-      children = children.map((node) => node is String ? new Text(node) : node).toList();
-    this._initElement(attributes, children, hostModule, needsShadow);
-  }
-  external void _initElement(Map<String, String> attributes, List children, Module hostModule, bool needsShadow);
-  // initialises the internal attributes table, which is a ordered list
-  // appends the given children nodes
-  // children must be Text or Element
-  // if needsShadow is true, creates a shadow tree
-
-  external bool hasAttribute(String name); // O(N) in number of attributes
-  external String getAttribute(String name); // O(N) in number of attributes
-  external void setAttribute(String name, [String value = '']); // O(N) in number of attributes
-  external void removeAttribute(String name); // O(N) in number of attributes
-  // calling setAttribute() with a null value removes the attribute
-  // (calling it without a value sets it to the empty string)
-
-  // Returns a new Array and new Attr instances every time.
-  external List<Attr> getAttributes(); // O(N) in number of attributes
-
-  external Root get shadowRoot; // O(1)
-  // returns the shadow root
-
-  void endTagParsedCallback() { }
-  void attributeChangedCallback(String name, String oldValue, String newValue) { }
-  // name will never be null when this is called by sky
-
-  // TODO(ianh): does a node ever need to know when it's been redistributed?
-
-  @override
-  Type getLayoutManager() { // O(1)
-    if (renderNode)
-      return renderNode.getProperty(phDisplay);
-    return super.getLayoutManager();
-  }
-}
-
-class Text extends Node {
-  external Text([String value = '']); // O(1)
-
-  external String get value; // O(1)
-  external void set (String value); // O(1)
-
-  void valueChangedCallback(String oldValue, String newValue) { }
-
-  @override
-  Type getLayoutManager() => TextLayoutManager; // O(1)
-}
-
-class Fragment extends ParentNode {
-  Fragment({List children}); // O(N) in number of arguments plus all their descendants
-  // children must be String, Text, or Element
-}
-
-class Root extends ParentNode {
-  Root({List children: null, this.host}) { // O(N) in number of children nodes plus all their descendants
-    if (children != null)
-      children = children.map((node) => node is String ? new Text(node) : node).toList();
-    this._initRoot(children);
-  }
-  external void _initRoot(List children);
-  // appends the given children nodes
-  // children must be Text or Element
-
-  final Element host;
-
-  external Element findId(String id); // O(1)
-  // throws if id is null
-}
-
-class ApplicationRoot extends Root {
-  ApplicationRoot ({List children}) : super(children: children); // O(N) in number of children nodes arguments plus all their descendants
-
-  @override
-  Type getLayoutManager() => rootLayoutManager; // O(1)
-}
-
-Type rootLayoutManager = BlockLayoutManager; // O(1)
-
-class SelectorQuery {
-  external SelectorQuery(String selector); // O(F()) where F() is the complexity of the selector
-
-  external bool matches(Element element); // O(F())
-  external Element find(Node root); // O(N*F())+O(M) where N is the number of descendants and M the average depth of the tree
-  external List<Element> findAll(Node root); // O(N*F())+O(N*M) where N is the number of descendants and M the average depth of the tree
-  // find() and findAll() throw if the root is not one of the following:
-  //  - Element
-  //  - Fragment
-  //  - Root
-}
-```
diff --git a/specs/frameworks.md b/specs/frameworks.md
deleted file mode 100644
index f7d91a517f6..00000000000
--- a/specs/frameworks.md
+++ /dev/null
@@ -1,31 +0,0 @@
-Frameworks
-----------
-
-Sky is intended to support multiple frameworks. Here is one way you
-could register a custom element using Dart annotations:
-
-```dart
-// @tagname annotation for registering elements
-// only useful when placed on classes that inherit from Element
-class tagname extends AutomaticMetadata {
-  const tagname(this.name);
-  final String name;
-  void init(DeclarationMirror target, Module module, ScriptElement script) {
-    assert(target is ClassMirror);
-    if (!(target as ClassMirror).isSubclassOf(reflectClass(Element)))
-      throw new UnsupportedError('@tagname can only be used on descendants of Element');
-    module.registerElement(name, (target as ClassMirror).reflectedType);
-  }
-}
-```
-
-A framework that used the above code could use the following code to
-get the tag name of an element:
-
-```dart
-String getTagName(Element element) { // O(N) in number of annotations on the class
-  // throws a StateError if the class doesn't have an @tagname annotation
-  var tagnameClass = reflectClass(tagname);
-  return (reflectClass(element.runtimeType).metadata.singleWhere((mirror) => mirror.type == tagnameClass).reflectee as tagname).name;
-}
-```
diff --git a/specs/markup.md b/specs/markup.md
deleted file mode 100644
index b35f937c6fb..00000000000
--- a/specs/markup.md
+++ /dev/null
@@ -1,222 +0,0 @@
-Sky Markup: Syntax
-==================
-
-A Sky file must consist of the following components:
-
- 1. If the file is intended to be a top-level Sky application, the
-    string "``#!mojo mojo:sky``" followed by a U+0020, U+000A or
-    U+000D character.
-
-    If the file is intended to be a module, then the string "SKY", a
-    U+0020 (space) character, the string "MODULE", and a U+0020,
-    U+000A or U+000D character.
-
-    These signatures make it more difficult to e.g. embed some Sky
-    markup into a PNG and then cause someone to import that image as a
-    module.
-
- 2. Zero or more of the following, in any order:
-     - comments
-     - text
-     - escapes
-     - elements
-
-Sky files must be encoded using UTF-8.
-
-A file that doesn't begin with the "``#!mojo mojo:sky``" signature
-isn't a Sky application file. For example:
-
-    #!mojo https://example.com/runtimes/sky.asmjs
-    Hello World
-
-...is not a Sky file, even if ``https://example.com/runtimes/sky.asmjs``
-is an implementation of the Sky runtime: it's just a file intended
-specifically for that runtime.
-
-The ``mojo:sky`` URL represents the generic Sky runtime provided by
-your Mojo runtime vendor.
-
-
-Comments
---------
-
-Comments start with the sequence "``<!--``" and end with the
-sequence "``-->``", where the start and end hyphens don't overlap.
-In between these characters, any sequence of characters is allowed
-except "``-->``", which terminates the comment. Comments cannot,
-therefore, be nested.
-
-
-Text
-----
-
-Any sequence of Unicode characters other than ``<``, ``&``, and
-U+0000.
-
-
-Escapes
--------
-
-There are three kinds of escapes:
-
-### Hex
-
-They begin with the sequence ``&#x`` or ``&#X``, followed by a
-sequence of hex characters (lowercase or uppercase), followed by a
-semicolon. The number 0 is not allowed.
-
-### Decimal
-
-They begin with the sequence ``&#`` or ``&#``, followed by a
-sequence of decimal characters, followed by a semicolon. The number 0
-is not allowed.
-
-### Named
-
-They begin with the sequence ``&``, followed by any characters,
-followed by a semicolon.
-
-The following names work:
-
-| Name | Character | Unicode |
-| ---- | --------- | ------- |
-| `lt` | `<` | U+003C LESS-THAN SIGN character |
-| `gt` | `>` | U+003E GREATER-THAN SIGN character |
-| `amp` | `&` | U+0026 AMPERSAND character |
-| `apos` | `'` | U+0027 APOSTROPHE character |
-| `quot` | `"` | U+0022 QUOTATION MARK character |
-
-
-Elements
---------
-
-An element consists of the following:
-
-1. ``<``
-2. Tag name: A sequence of characters other than ``/``, ``>``,
-   U+0020, U+000A, U+000D (whitespace).
-3. Zero or more of the following:
-   1. One or more U+0020, U+000A, U+000D (whitespace).
-   2. Attribute name: A sequence of characters other than ``/``,
-      ``=``, ``>``, U+0020, U+000A, U+000D (whitespace).
-   3. Optionally:
-      1. Zero or more U+0020, U+000A, U+000D (whitespace) characters.
-      2. ``=``
-      3. Zero or more U+0020, U+000A, U+000D (whitespace) characters.
-      4. Attribute value: Either:
-         - ``'`` followed by attribute text other than ``'``
-           followed by a terminating ``'``.
-         - ``"`` followed by attribute text other than ``'``
-           followed by a terminating ``"``.
-         - attribute text other than ``/``, ``>``,
-           U+0020, U+000A, U+000D (whitespace).
-         "Attribute text" is escapes or any unicode characters other
-         than U+0000.
-4. Either:
-   - For a void element:
-     1. ``/``, indicating an empty element.
-     2. ``>``
-   - For a non-void element:
-     2. ``>``
-     3. The element's contents:
-        - If the element's tag name is ``script``, then any sequence of
-          characters other than U+0000, but there must not be the
-          substring ``</script``. The sequence must be valid sky script.
-        - If the element's tag name is ``style``, then any sequence of
-          characters other than U+0000, but there must not be the
-          substring ``</style``. The sequence must be valid sky style.
-        - Otherwise, zero or more of the following, in any order:
-          - comments
-          - text
-          - escapes
-          - elements
-     4. Finally, the end tag, which may be omitted if the element's tag
-        name is not ``template``, consisting of:
-        1. ``<``
-        2. ``/``
-        3. Same sequence of characters as "tag name" above; this may
-           be omitted if no start tags have had their end tag omitted
-           since this element's start tag, unless this element's tag
-           name is ``script`` or ``style``.
-        4. ``>``
-
-
-Sky Markup: Elements
-====================
-
-The Sky language consists of very few elements, since it is expected
-that everything of note would be provided by frameworks.
-
-The following elements are implicitly registered by default, even if
-you haven't imported anything. You can get to their constructors if
-you import dart:sky (basically, dart:sky is always imported by defaul;
-it's the runtime library). None of these elements have shadow trees.
-
-``<import src="foo.sky">``
- - Downloads and imports foo.sky in the background.
-
-``<import src="foo.sky" as="foo">``
- - Downloads and imports foo.sky in the background, using "foo" as its
-   local name (see ``<script>``).
-
-``<template>``
- - The contents of the element aren't placed in the Element itself.
-   They are instead placed into a Fragment that you can obtain from
-   the element's "content" attribute.
-
-``<script>``
- - Blocks until all previous imports have been loaded, then loads the
-   library given in the script block, as described in
-   [scripts.md](scripts.md).
-
-``<style>``
- - Adds the contents to the module's styles.
-
-``<content>``
-``<content select="...">``
- - In a shadow tree, acts as an insertion point for distributed nodes.
-   The select="" attribute gives the selector to use to pick the nodes
-   to place in this insertion point; it defaults to everything.
-
-``<img src="foo.bin">``
- - Sky fetches the bits for foo.bin, looks for a decoder for those
-   bits, and renders the bits that the decoder returns.
-
-``<div>``
- - Element that does nothing.
-
-``<span>``
- - Element that does nothing.
-
-``<iframe src="foo.bin">``
- - Sky tells mojo to open an application for foo.bin, and hands that
-   application a view so that the application can render appropriately.
-
-``<t>``
- - Within a ``<t>`` section, whitespace is not trimmed from the start and
-   end of text nodes by the parser.
-   TOOD(ianh): figure out if the authoring aesthetics of this are ok
-
-``<a href="foo.bin">``
- - A widget that, when invoked, causes mojo to open a new application
-   for "foo.bin".
-
-``<title>``
- - Sets the contents as the application's title (as provided by Sky to
-   the view manager). (Actually just ensures that any time the element
-   is mutated, module.application.title is set to the element's
-   contents.)
-
-
-Sky Markup: Global Attributes
-=============================
-
-The following attributes are available on all elements:
-
-* ``id=""`` (any value)
-* ``class=""`` (any value, space-separated)
-* ``style=""`` (declaration part of a Sky style rule)
-* ``lang=""`` (language code)
-* ``dir=""`` (ltr or rtl only)
-* ``contenteditable=""`` (subject to future developments)
-* ``tabindex=""`` (subject to future developments)
diff --git a/specs/modules.md b/specs/modules.md
deleted file mode 100644
index 13c8ebb26b6..00000000000
--- a/specs/modules.md
+++ /dev/null
@@ -1,148 +0,0 @@
-Sky Module System
-=================
-
-This document describes the Sky module system.
-
-Overview
---------
-
-The Sky module system is based on the ``import`` element. In its
-most basic form, you import a module as follows:
-
-```html
-<import src="path/to/module.sky" />
-```
-
-As these ``import`` elements are inserted into a module's element
-tree, the module's list of outstanding dependencies grows. When an
-imported module completes, it is removed from the importing module's
-list of outstanding dependencies.
-
-Before compiling script or inserting an element that is not already
-registered, the parser waits until the list of outstanding
-dependencies is empty. After the parser has finished parsing, the
-module waits until its list of outstanding dependencies is empty
-before marking itself complete.
-
-The ``as`` attribute on the ``import`` element binds a name to the
-imported module:
-
-```html
-<import src="path/to/chocolate.sky" as="chocolate" />
-```
-
-Each module implicitly imports the [Built-In Elements
-Module](builtins.md).
-
-When a module imports another, and the ``import`` element has no
-``as`` attribute, then any elements registered in that module whose
-tag names do not begin with an underscore must be registered on the
-importing module. (If multiple elements are registered with the same
-name, that name gets marked as dead for that module and all the
-registrations for that name are discarded.)
-
-TODO(ianh): decide if elements imported with "as" should be imported
-but with the "as" name prefixed, as in ``<foo.button>``
-
-
-Module API
-----------
-
-Each module consists of one or more libraries. The first library in a
-module is the *element tree library*, which consists of the following
-code for a Sky module:
-
-```dart
-import 'dart:sky';
-final Module module = new Module();
-```
-
-...and the following code for a Sky application:
-
-```dart
-import 'dart:sky';
-final Module module = new Application();
-```
-
-The ``<script>`` elements found in the module's element tree create
-the subsequent libraries. Each one first imports the ``dart:mirror``
-library, then the ``dart:sky`` module, then the first library
-described above, then all the modules referenced by ``<import>``
-element up to that ``<script>`` element and all the libraries defined
-by ``<script>`` elements up to that point, interleaved so as to
-maintain the same relative order as those elements were first seen by
-the parser.
-
-When a library imports a module, it actually imports all the libraries
-that were declared by that module except the aforementioned element
-tree library. If the ``as`` attribute is present on the ``import``
-element, all the libraries are bound to the same name.
-
-At the end of the ``<script>`` block's source, if it parsed correctly
-and completely, the conceptual equivalent of the following code is
-appended (but without affecting the library's list of declarations and
-without any possibility of it clashing with identifiers described in
-the library itself):
-
-```dart
-class _ { }
-void main(ScriptElement script) {
-  LibraryMirror library = reflectClass(_).owner as LibraryMirror;
-  if (library.declarations.containsKey(#_init) && library.declarations[#_init] is MethodMirror)
-    _init(script);
-  AutomaticMetadata.runLibrary(library, module, script);
-}
-```
-
-Then, that ``main(script)`` function is called, with ``script`` set to
-the ``ScriptElement`` object representing the relevant ``<script>``
-element.
-
-TODO(ianh): decide what URL and name we should give the libraries, as
-exposed in MirrorSystem.getName(libraryMirror.qualifiedName) etc
-
-The ``Module`` class is defined in ``dart:sky`` as follows:
-
-```dart
-abstract class AbstractModule extends EventTarget {
-  AbstractModule({this.url, this.elements});
-
-  final String url;
-
-  final Root elements; // O(1)
-  // the Root node of the module or application's element tree
-
-  external Future<Module> import(String url); // O(Yikes)
-  // load and return the URL at the given Module
-  // if it's already loaded, the future will resolve immediately
-  // if loading fails, the future will have an error
-
-  external List<Module> getImports(); // O(N)
-  // returns the Module objects of all the imported modules
-
-  external void registerElement(String tagname, Type elementClass); // O(1)
-  // registers a tag name with the parser
-  // only useful during parse time
-  // verify that tagname isn't null or empty
-  // verify that elementClass is the Type of a class that extends Element (directly or indirectly, but not via "implements" or "with")
-  // (see the @tagname code for an example of how to verify that from dart)
-  // verify that there's not already a class registered for this tag name
-  // if there is, then mark this tagname is broken, so that it acts as if it's not registered in the parser,
-  // and, if this is the first time it was marked broken, log a console message regarding the issue
-  // (mention the tag name but not the classes, so that it's not observable that this currently happens out of order)
-}
-
-class Module extends AbstractModule {
-  Module({String url, Root elements, this.application}) :
-    super(url: url, elements: elements); // O(1)
-  final Application application; // O(1)
-}
-
-class Application extends AbstractModule {
-  Application({String url, Root elements, this.gestureManager}) :
-    super(url: url, elements: elements); // O(1)
-  external String get title; // O(1)
-  external void set title(String newValue); // O(1)
-  final GestureManager gestureManager;
-}
-```
diff --git a/specs/parsing.md b/specs/parsing.md
deleted file mode 100644
index d42f6575db3..00000000000
--- a/specs/parsing.md
+++ /dev/null
@@ -1,846 +0,0 @@
-Parsing
-=======
-
-Parsing in Sky is a strict pipeline consisting of five stages:
-
-- decoding, which converts incoming bytes into Unicode characters
-  using UTF-8.
-
-- normalising, which manipulates the sequence of characters.
-
-- tokenising, which converts these characters into four kinds of
-  tokens: character tokens, start tag tokens, end tag tokens, and
-  automatic end tag tokens. Character tokens have a single character
-  value. Start and end tag tokens have a tag name, and a list of
-  name/value pairs known as attributes.
-
-- token cleanup, which converts sequences of character tokens into
-  string tokens, and removes duplicate attributes in tag tokens.
-
-- tree construction, which converts these tokens into a tree of nodes.
-
-Later stages cannot affect earlier stages.
-
-When a sequence of bytes is to be parsed, there is always a defined
-_parsing context_, which is either an Application object or a Module
-object.
-
-
-Decoding stage
---------------
-
-To decode a sequence of bytes _bytes_ for parsing, the [utf-8
-decode](https://encoding.spec.whatwg.org/#utf-8-decode) algorithm must
-be used to transform _bytes_ into a sequence of characters
-_characters_.
-
-Note: The decoder will strip a leading BOM if any.
-
-This sequence must then be passed to the normalisation stage.
-
-
-Normalisation stage
--------------------
-
-To normalise a sequence of characters, apply the following rules:
-
-* Any U+000D character followed by a U+000A character must be removed.
-
-* Any U+000D character not followed by a U+000A character must be
-  converted to a U+000A character.
-
-* Any U+0000 character must be converted to a U+FFFD character.
-
-The converted sequence of characters must then be passed to the
-tokenisation stage.
-
-
-Tokenisation stage
-------------------
-
-To tokenise a sequence of characters, a state machine is used.
-
-Initially, the state machine must begin in the **signature** state.
-
-Each character in turn must be processed according to the rules of the
-state at the time the character is processed. A character is processed
-once it has been _consumed_. This produces a stream of tokens; the
-tokens must be passed to the token cleanup stage.
-
-When the last character is consumed, the tokeniser ends.
-
-
-### Expecting a string ###
-
-When the user agent is to _expect a string_, it must run these steps:
-
-1. Let _expectation_ be the string to expect. When this string is
-   indexed, the first character has index 0.
-
-2. Assertion: The first character in _expectation_ is the current
-   character, and _expectation_ has more than one character.
-
-3. Consume the current character.
-
-4. Let _index_ be 1.
-
-5. Let _success_ and _failure_ be the states specified for success and
-   failure respectively.
-
-6. Switch to the **expect a string** state.
-
-
-### Tokeniser states ###
-
-#### **Signature** state ####
-
-If the current character is...
-
-* '``#``': If the _parsing context_ is not an Application, switch to
-  the _failed signature_ state. Otherwise, expect the string
-  "``#!mojo mojo:sky``", with _after signature_ as the _success_
-  state and _failed signature_ as the _failure_ state.
-
-* '``S``': If the _parsing context_ is not a Module, switch to the
-  _failed signature_ state. Otherwise, expect the string
-  "``SKY MODULE``", with _after signature_ as the _success_ state,
-  and _failed signature_ as the _failure_ state.
-
-* Anything else: Jump to the **failed signature** state.
-
-
-#### **Expect a string** state ####
-
-If the current character is not the same as the <i>index</i>th character in
-_expectation_, then switch to the _failure_ state.
-
-Otherwise, consume the character, and increase _index_. If _index_ is
-now equal to the length of _expectation_, then switch to the _success_
-state.
-
-
-#### **After signature** state ####
-
-If the current character is...
-
-* U+000A: Consume the character and switch to the **data** state.
-* U+0020: Consume the character and switch to the **consume rest of
-  line** state.
-* Anything else: Switch to the **failed signature** state.
-
-
-#### **Failed signature** state ####
-
-Stop parsing. No tokens are emitted. The file is not a sky file.
-
-
-#### **Consume rest of line** state ####
-
-If the current character is...
-
-* U+000A: Consume the character and switch to the **data** state.
-* Anything else: Consume the character and stay in this state.
-
-
-#### **Data** state ####
-
-If the current character is...
-
-* '``<``': Consume the character and switch to the **tag open** state.
-
-* '``&``': Consume the character and switch to the **character
-  reference** state, with the _return state_ set to the **data**
-  state, and the _emitting operation_ being to emit a character token
-  for the given character.
-
-* Anything else: Emit the current input character as a character
-  token. Consume the character. Stay in this state.
-
-
-#### **Script raw data** state ####
-
-If the current character is...
-
-* '``<``': Consume the character and switch to the **script raw
-  data: close 1** state.
-
-* Anything else: Emit the current input character as a character
-  token. Consume the character. Stay in this state.
-
-
-#### **Script raw data: close 1** state ####
-
-If the current character is...
-
-* '``/``': Consume the character and switch to the **script raw
-  data: close 2** state.
-
-* Anything else: Emit '``<``' character tokens. Switch to the
-  **script raw data** state without consuming the character.
-
-
-#### **Script raw data: close 2** state ####
-
-If the current character is...
-
-* '``s``': Consume the character and switch to the **script raw
-  data: close 3** state.
-
-* Anything else: Emit '``</``' character tokens. Switch to the
-  **script raw data** state without consuming the character.
-
-
-#### **Script raw data: close 3** state ####
-
-If the current character is...
-
-* '``c``': Consume the character and switch to the **script raw
-  data: close 4** state.
-
-* Anything else: Emit '``</s``' character tokens. Switch to the
-  **script raw data** state without consuming the character.
-
-
-#### **Script raw data: close 4** state ####
-
-If the current character is...
-
-* '``r``': Consume the character and switch to the **script raw
-  data: close 5** state.
-
-* Anything else: Emit '``</sc``' character tokens. Switch to the
-  **script raw data** state without consuming the character.
-
-
-#### **Script raw data: close 5** state ####
-
-If the current character is...
-
-* '``i``': Consume the character and switch to the **script raw
-  data: close 6** state.
-
-* Anything else: Emit '``</scr``' character tokens. Switch to the
-  **script raw data** state without consuming the character.
-
-
-#### **Script raw data: close 6** state ####
-
-If the current character is...
-
-* '``p``': Consume the character and switch to the **script raw
-  data: close 7** state.
-
-* Anything else: Emit '``</scri``' character tokens. Switch to the
-  **script raw data** state without consuming the character.
-
-
-#### **Script raw data: close 7** state ####
-
-If the current character is...
-
-* '``t``': Consume the character and switch to the **script raw
-  data: close 8** state.
-
-* Anything else: Emit '``</scrip``' character tokens. Switch to the
-  **script raw data** state without consuming the character.
-
-
-#### **Script raw data: close 8** state ####
-
-If the current character is...
-
-* U+0020, U+000A, '``/``', '``>``': Create an end tag token, and
-  let its tag name be the string '``script``'. Switch to the
-  **before attribute name** state without consuming the character.
-
-* Anything else: Emit '``</script``' character tokens. Switch to the
-  **script raw data** state without consuming the character.
-
-
-#### **Style raw data** state ####
-
-If the current character is...
-
-* '``<``': Consume the character and switch to the **style raw
-  data: close 1** state.
-
-* Anything else: Emit the current input character as a character
-  token. Consume the character. Stay in this state.
-
-
-#### **Style raw data: close 1** state ####
-
-If the current character is...
-
-* '``/``': Consume the character and switch to the **style raw
-  data: close 2** state.
-
-* Anything else: Emit '``<``' character tokens. Switch to the
-  **style raw data** state without consuming the character.
-
-
-#### **Style raw data: close 2** state ####
-
-If the current character is...
-
-* '``s``': Consume the character and switch to the **style raw
-  data: close 3** state.
-
-* Anything else: Emit '``</``' character tokens. Switch to the
-  **style raw data** state without consuming the character.
-
-
-#### **Style raw data: close 3** state ####
-
-If the current character is...
-
-* '``t``': Consume the character and switch to the **style raw
-  data: close 4** state.
-
-* Anything else: Emit '``</s``' character tokens. Switch to the
-  **style raw data** state without consuming the character.
-
-
-#### **Style raw data: close 4** state ####
-
-If the current character is...
-
-* '``y``': Consume the character and switch to the **style raw
-  data: close 5** state.
-
-* Anything else: Emit '``</st``' character tokens. Switch to the
-  **style raw data** state without consuming the character.
-
-
-#### **Style raw data: close 5** state ####
-
-If the current character is...
-
-* '``l``': Consume the character and switch to the **style raw
-  data: close 6** state.
-
-* Anything else: Emit '``</sty``' character tokens. Switch to the
-  **style raw data** state without consuming the character.
-
-
-#### **Style raw data: close 6** state ####
-
-If the current character is...
-
-* '``e``': Consume the character and switch to the **style raw
-  data: close 7** state.
-
-* Anything else: Emit '``</styl``' character tokens. Switch to the
-  **style raw data** state without consuming the character.
-
-
-#### **Style raw data: close 7** state ####
-
-If the current character is...
-
-* U+0020, U+000A, '``/``', '``>``': Create an end tag token, and
-  let its tag name be the string '``style``'. Switch to the
-  **before attribute name** state without consuming the character.
-
-* Anything else: Emit '``</style``' character tokens. Switch to the
-  **style raw data** state without consuming the character.
-
-
-#### **Tag open** state ####
-
-If the current character is...
-
-* '``!``': Consume the character and switch to the **comment start
-  1** state.
-
-* '``/``': Consume the character and switch to the **close tag
-  state** state.
-
-* '``>``': Emit character tokens for '``<>``'. Consume the current
-  character. Switch to the **data** state.
-
-* '``0``'..'``9``', '``a``'..'``z``', '``A``'..'``Z``',
-  '``-``', '``_``', '``.``': Create a start tag token, let its
-  tag name be the current character, consume the current character and
-  switch to the **tag name** state.
-
-* Anything else: Emit the character token for '``<``'. Switch to the
-  **data** state without consuming the current character.
-
-
-#### **Close tag** state ####
-
-If the current character is...
-
-* '``>``': Emit an automatic end tag token. Switch to the **data**
-  state.
-
-* '``0``'..'``9``', '``a``'..'``z``', '``A``'..'``Z``',
-  '``-``', '``_``', '``.``': Create an end tag token, let its
-  tag name be the current character, consume the current character and
-  switch to the **tag name** state.
-
-* Anything else: Emit the character tokens for '``</``'. Switch to
-  the **data** state without consuming the current character.
-
-
-#### **Tag name** state ####
-
-If the current character is...
-
-* U+0020, U+000A: Consume the current character. Switch to the
-  **before attribute name** state.
-
-* '``/``': Consume the current character. Switch to the **void tag**
-  state.
-
-* '``>``': Consume the current character. Switch to the **after
-  tag** state.
-
-* Anything else: Append the current character to the tag name, and
-  consume the current character. Stay in this state.
-
-
-#### **Void tag** state ####
-
-If the current character is...
-
-* '``>``': Consume the current character. Switch to the **after void
-  tag** state.
-
-* Anything else: Switch to the **before attribute name** state without
-  consuming the current character.
-
-
-#### **Before attribute name** state ####
-
-If the current character is...
-
-* U+0020, U+000A: Consume the current character. Stay in this state.
-
-* '``/``': Consume the current character. Switch to the **void tag**
-  state.
-
-* '``>``': Consume the current character. Switch to the **after
-  tag** state.
-
-* Anything else: Create a new attribute in the tag token, and set its
-  name to the current character and its value to the empty string.
-  Consume the current character. Switch to the **attribute name**
-  state.
-
-
-#### **Attribute name** state ####
-
-If the current character is...
-
-* U+0020, U+000A: Consume the current character. Switch to the **after
-  attribute name** state.
-
-* '``/``': Consume the current character. Switch to the **void tag**
-  state.
-
-* '``=``': Consume the current character. Switch to the **before
-  attribute value** state.
-
-* '``>``': Consume the current character. Switch to the **after
-  tag** state.
-
-* Anything else: Append the current character to the most recently
-  added attribute's name, and consume the current character. Stay in
-  this state.
-
-
-#### **After attribute name** state ####
-
-If the current character is...
-
-* U+0020, U+000A: Consume the current character. Stay in this state.
-
-* '``/``': Consume the current character. Switch to the **void tag**
-  state.
-
-* '``=``': Consume the current character. Switch to the **before
-  attribute value** state.
-
-* '``>``': Consume the current character. Switch to the **after
-  tag** state.
-
-* Anything else: Create a new attribute in the tag token, and set its
-  name to the current character and its value to the empty string.
-  Consume the current character. Switch to the **attribute name**
-  state.
-
-
-#### **Before attribute value** state ####
-
-If the current character is...
-
-* U+0020, U+000A: Consume the current character. Stay in this state.
-
-* '``>``': Consume the current character. Switch to the **after
-  tag** state.
-
-* '``'``': Consume the current character. Switch to the
-  **single-quoted attribute value** state.
-
-* '``"``': Consume the current character. Switch to the
-  **double-quoted attribute value** state.
-
-* Anything else: Switch to the **unquoted attribute value** state
-  without consuming the current character.
-
-
-#### **Single-quoted attribute value** state ####
-
-If the current character is...
-
-* '``'``': Consume the current character. Switch to the
-  **before attribute name** state.
-
-* '``&``': Consume the character and switch to the **character
-  reference** state, with the _return state_ set to the
-  **single-quoted attribute value** state and the _emitting operation_
-  being to append the given character to the value of the most
-  recently added attribute.
-
-* Anything else: Append the current character to the value of the most
-  recently added attribute. Consume the current character. Stay in
-  this state.
-
-
-#### **Double-quoted attribute value** state ####
-
-If the current character is...
-
-* '``"``': Consume the current character. Switch to the
-  **before attribute name** state.
-
-* '``&``': Consume the character and switch to the **character
-  reference** state, with the _return state_ set to the
-  **double-quoted attribute value** state and the _emitting operation_
-  being to append the given character to the value of the most
-  recently added attribute.
-
-* Anything else: Append the current character to the value of the most
-  recently added attribute. Consume the current character. Stay in
-  this state.
-
-
-#### **Unquoted attribute value** state ####
-
-If the current character is...
-
-* U+0020, U+000A: Consume the current character. Switch to the
-  **before attribute name** state.
-
-* '``>``': Consume the current character. Switch to the **after tag**
-  state.
-
-* '``&``': Consume the character and switch to the **character
-  reference** state, with the _return state_ set to the **unquoted
-  attribute value** state, and the _emitting operation_ being to
-  append the given character to the value of the most recently added
-  attribute.
-
-* Anything else: Append the current character to the value of the most
-  recently added attribute. Consume the current character. Stay in
-  this state.
-
-
-#### **After tag** state ####
-
-Emit the tag token.
-
-If the tag token was a start tag token and the tag name was
-'``script``', then switch to the **script raw data** state.
-
-If the tag token was a start tag token and the tag name was
-'``style``', then switch to the **style raw data** state.
-
-Otherwise, switch to the **data** state.
-
-
-#### **After void tag** state ####
-
-Emit the tag token.
-
-If the tag token is a start tag token, emit an end tag token with the
-same tag name.
-
-Switch to the **data** state.
-
-
-#### **Comment start 1** state ####
-
-If the current character is...
-
-* '``-``': Consume the character and switch to the **comment start
-  2** state.
-
-* Anything else: Emit character tokens for '``<!``'. Switch to the
-  **data** state without consuming the current character.
-
-
-#### **Comment start 2** state ####
-
-If the current character is...
-
-* '``-``': Consume the character and switch to the **comment**
-  state.
-
-* Anything else: Emit character tokens for '``<!-``'. Switch to the
-  **data** state without consuming the current character.
-
-
-#### **Comment** state ####
-
-If the current character is...
-
-* '``-``': Consume the character and switch to the **comment end 1**
-  state.
-
-* Anything else: Consume the character and stay in this state.
-
-
-#### **Comment end 1** state ####
-
-If the current character is...
-
-* '``-``': Consume the character, switch to the **comment end 2**
-  state.
-
-* Anything else: Consume the character, and switch to the **comment**
-  state.
-
-
-#### **Comment end 2** state ####
-
-If the current character is...
-
-* '``>``': Consume the character and switch to the **data** state.
-
-* '``-``': Consume the character, but stay in this state.
-
-* Anything else: Consume the character, and switch to the **comment**
-  state.
-
-
-#### **Character reference** state ####
-
-Let _raw value_ be the string '``&``'.
-
-Append the current character to _raw value_.
-
-If the current character is...
-
-* '``#``': Consume the character, and switch to the **numeric
-  character reference** state.
-
-* '``0``'..'``9``', '``a``'..'``f``', '``A``'..'``F``': switch to the
-  **named character reference** state without consuming the current
-  character.
-
-* Anything else: Run the _emitting operation_ for all but the last
-  character in _raw value_, and switch to the _return state_ without
-  consuming the current character.
-
-
-#### **Numeric character reference** state ####
-
-Append the current character to _raw value_.
-
-If the current character is...
-
-* '``x``', '``X``': Consume the character and switch to the **before
-  hexadecimal numeric character reference** state.
-
-* '``0``'..'``9``': Let _value_ be the numeric value of the
-  current character interpreted as a decimal digit, consume the
-  character, and switch to the **decimal numeric character reference**
-  state.
-
-* Anything else: Run the _emitting operation_ for all but the last
-  character in _raw value_, and switch to the _return state_ without
-  consuming the current character.
-
-
-#### **Before hexadecimal numeric character reference** state ####
-
-Append the current character to _raw value_.
-
-If the current character is...
-
-* '``0``'..'``9``', '``a``'..'``f``', '``A``'..'``F``':
-  Let _value_ be the numeric value of the current character
-  interpreted as a hexadecimal digit, consume the character, and
-  switch to the **hexadecimal numeric character reference** state.
-
-* Anything else: Run the _emitting operation_ for all but the last
-  character in _raw value_, and switch to the _return state_ without
-  consuming the current character.
-
-
-#### **Hexadecimal numeric character reference** state ####
-
-Append the current character to _raw value_.
-
-If the current character is...
-
-* '``0``'..'``9``', '``a``'..'``f``', '``A``'..'``F``':
-  Let _value_ be sixteen times _value_ plus the numeric value of the
-  current character interpreted as a hexadecimal digit.
-
-* '``;``': Consume the character. If _value_ is between 0x0001 and
-  0x10FFFF inclusive, but is not between 0xD800 and 0xDFFF inclusive,
-  run the _emitting operation_ with a unicode character having the
-  scalar value _value_; otherwise, run the _emitting operation_ with
-  the character U+FFFD. Then, in either case, switch to the _return
-  state_.
-
-* Anything else: Run the _emitting operation_ for all but the last
-  character in _raw value_, and switch to the _return state_ without
-  consuming the current character.
-
-
-#### **Decimal numeric character reference** state ####
-
-Append the current character to _raw value_.
-
-If the current character is...
-
-* '``0``'..'``9``': Let _value_ be ten times _value_ plus the
-  numeric value of the current character interpreted as a decimal
-  digit.
-
-* '``;``': Consume the character. If _value_ is between 0x0001 and
-  0x10FFFF inclusive, but is not between 0xD800 and 0xDFFF inclusive,
-  run the _emitting operation_ with a unicode character having the
-  scalar value _value_; otherwise, run the _emitting operation_ with
-  the character U+FFFD. Then, in either case, switch to the _return
-  state_.
-
-* Anything else: Run the _emitting operation_ for all but the last
-  character in _raw value_, and switch to the _return state_ without
-  consuming the current character.
-
-
-#### **Named character reference** state ####
-
-Append the current character to _raw value_.
-
-If the current character is...
-
-* '``;``': Consume the character.
-  If the _raw value_ is...
-
-  - '``&amp;``: Emit Run the _emitting operation_ for the character
-    '``&``'.
-
-  - '``&apos;``: Emit Run the _emitting operation_ for the character
-    '``'``'.
-
-  - '``&gt;``: Emit Run the _emitting operation_ for the character
-    '``>``'.
-
-  - '``&lt;``: Emit Run the _emitting operation_ for the character
-    '``<``'.
-
-  - '``&quot;``: Emit Run the _emitting operation_ for the character
-    '``"``'.
-
-  Then, switch to the _return state_.
-
-* '``0``'..'``9``', '``a``'..'``z``', '``A``'..'``Z``': Consume the
-  character and stay in this state.
-
-* Anything else: Run the _emitting operation_ for all but the last
-  character in _raw value_, and switch to the _return state_ without
-  consuming the current character.
-
-
-Token cleanup stage
--------------------
-
-Replace each sequence of character tokens with a single string token
-whose value is the concatenation of all the characters in the
-character tokens.
-
-For each start tag token, remove all but the first name/value pair for
-each name (i.e. remove duplicate attributes, keeping only the first
-one).
-
-TODO(ianh): maybe sort the attributes?
-
-For each end tag token, remove the attributes entirely.
-
-If the token is a start tag token, notify the JavaScript token stream
-callback of the token.
-
-Then, pass the tokens to the tree construction stage.
-
-
-Tree construction stage
------------------------
-
-To construct a node tree from a _sequence of tokens_ and an element
-tree rooted at a `Root` node _root_ (this is implemented in JS):
-
-1. Initialize the _stack of open nodes_ to be _root_.
-2. Initialize _imported modules_ to an empty list.
-3. Consider each token _token_ in the _sequence of tokens_ in turn, as
-   follows. If a token is to be skipped, then jump straight to the
-   next token, without doing any more work with the skipped token.
-   - If _token_ is a string token,
-     1. If the value of the token contains only U+0020 and U+000A
-        characters, and there is no ``t`` element on the _stack of
-        open nodes_, then skip the token.
-     2. Create a text node _node_ whose character data is the value of
-        the token.
-     3. Append _node_ to the top node in the _stack of open nodes_.
-   - If _token_ is a start tag token,
-     1. If the tag name isn't a registered tag name, then yield until
-        _imported modules_ contains no entries with unresolved
-        promises.
-     2. If the tag name is not registered, then let the ErrorElement
-        constructor from dart:sky be the element constructor.
-        Otherwise, let the element constructor be the registered
-        element's constructor for that tag name in this module.
-     3. Create an element _node_ with the attributes given by the
-        token by calling the constructor.
-     4. If _node_ is not an Element object, then let the constructor
-        be the ErrorElement constructor and return to the previous
-        step.
-     5. Append _node_ to the top node in the _stack of open nodes_.
-     6. Push _node_ onto the top of the _stack of open nodes_.
-     7. If _node_ is a ``template`` element, then:
-        1. Let _fragment_ be the ``Fragment`` object that the
-           ``template`` element uses as its template contents
-           container.
-        2. Push _fragment_ onto the top of the _stack of open nodes_.
-        If _node_ is an ``import`` element, then:
-        1. Let ``url`` be the value of _node_'s ``src`` attribute.
-        2. Call ``parsing context``'s ``importModule()`` method,
-           passing it ``url``.
-        3. Add the returned promise to _imported modules_; if _node_
-           has an ``as`` attribute, associate the entry with that
-           name.
-   - If _token_ is an end tag token:
-     1. If the tag name is registered, let _tag name_ be that tag
-        name. Otherwise, let _tag name_ be "error".
-     2. Let _node_ be the topmost node in the _stack of open nodes_
-        whose tag name is _tag name_, if any. If there isn't one, skip
-        this token.
-     3. If there's a ``template`` element in the _stack of open
-        nodes_ above _node_, then skip this token.
-     4. Pop nodes from the _stack of open nodes_ until _node_ has been
-        popped.
-     5. If _node_'s tag name is ``script``, then yield until _imported
-        modules_ contains no entries with unresolved promises, then
-        execute the script given by the element's contents, using the
-        associated names as appropriate.
-   - If _token_ is an automatic end tag token:
-     1. Pop the top node from the _stack of open nodes_, unless it is
-        the _root_ node.
-4. Yield until _imported modules_ has no promises.
-5. Fire a ``load`` event at the _parsing context_ object.
diff --git a/specs/runloop.md b/specs/runloop.md
deleted file mode 100644
index b080090af1b..00000000000
--- a/specs/runloop.md
+++ /dev/null
@@ -1,144 +0,0 @@
-Sky's Run Loop
-==============
-
-Sky has three task queues, named idle, frame, and nextFrame.
-
-When a task is run, it has a time budget, and if the time budget is
-exceeded, then a catchable DeadlineExceededException exception is
-fired.
-
-```dart
-class DeadlineExceededException implements Exception { }
-```
-
-There is a method you can use that guards your code against these
-exceptions:
-
-```dart
-typedef void Callback();
-external guardAgainstDeadlineExceptions(Callback callback);
-// runs callback.
-// if the time budget for the _task_ expires while the callback is
-// running, the callback isn't interrupted, but the method will throw
-// an exception once the callback returns.
-```
-
-When Sky is to *process a task queue until a particular time*, with a
-queue *relevant task queue*, bits *filter bits*, a time
-*particular time*, and an *idle rule* which is either "sleep" or
-"abort", it must run the following steps:
-
-1. Let *remaining time* be the time until the given *particular time*.
-2. If *remaining time* is less than or equal to zero, exit this
-   algorithm.
-3. Let *task list* be the list of tasks in the *relevant task queue*
-   that have bits that, when 'and'ed with *filter bits*, are equal to
-   *filter bits*, whose required budget is less than or equal to
-   *remaining time*; and whose due time, if any, has been reached.
-4. If *task list* is empty, then if *idle rule* is "sleep" then return
-   to step 1, otherwise, exit this algorithm.
-5. Sort *task list* by the priority of each task, highest first.
-6. Remove the top task from *task list* from the *relevant task
-   queue*, and let that be *selected task*.
-7. Run *selected task*, with a budget of *remaining time* or 1ms,
-   whichever is shorter.
-8. Return to step 1.
-
-When Sky is to *drain a task queue for a specified time*, with a queue
-*relevant task queue*, bits *filter bits*, and a duration *budget*, it
-must run the following steps:
-
-2. Let *task list* be the list of tasks in the *relevant task queue*
-   that have bits that, when 'or'ed with *filter bits*, are non-zero;
-   and whose required budget is less than or equal to *budget*.
-4. If *task list* is empty, then exit.
-5. Sort *task list* by the priority of each task, highest first.
-6. Remove the top task from *task list* from the *relevant task
-   queue*, and let that be *selected task*.
-7. Run *selected task*, with a budget of *budget*.
-8. Decrease *budget* with the amount of time that *selected task* took
-   to run.
-9. If *selected task* threw an uncaught DeadlineExceededException
-   exception, then cancel all the tasks in *relevant task queue*.
-   Otherwise, return to step 2.
-
-Sky's run loop consists of running the following, at 120Hz (each loop
-takes 8.333ms):
-
-1. *Drain* the *frame task queue*, with bits
-   `application.frameTaskBits`, for 1ms.
-
-2. Create a task that does the following, then run it with a budget of
-   1ms:
-
-   1. Update the render tree, including calling childAdded(),
-      childRemoved(), and getLayoutManager() as needed, catching any
-      exceptions other than DeadlineExceededException exceptions.
-
-   If an exception is thrown by this, then the RenderNode tree will
-   continue to not quite match the element tree, which is fine.
-
-3. If there are no tasks on the *idle task queue* with bits
-   `LayoutKind`, create a task that tells the root node to layout if
-   it has needsLayout or descendantNeedsLayout, mark that with
-   priority 0 and bits `LayoutKind`, and add it to the *idle task
-   queue*.
-
-4. *Process* the *idle task queue*, with bits `LayoutKind`, with a
-   target time of t-1ms, where t is the time at which we have to send
-   the frame to the GPU, and with an *idle rule* of "abort".
-
-5. Create a task that does the following, then run it with a budget of
-   1ms:
-
-   1. If there are no RenderNodes that need paint, abort.
-
-   2. Call the `paint()` callback of the RenderNode that was least
-      recently marked as needing paint, catching any exceptions other
-      than DeadlineExceededException exceptions.
-
-   3. Jump to step 1.
-
-   If an exception is thrown by this, then some RenderNode objects
-      will be out-of-date during the paint.
-
-6. Send frame to GPU.
-
-7. Replace the frame queue with the nextFrame queue, and let the
-   nextFrame queue be an empty queue.
-
-8. *Process* the *idle task queue*, with bits
-   `application.idleTaskBits`, with a target time of t, where t is the
-   time at which we have to start the next frame's layout and paint
-   computations, and with an *idle rule* of "sleep".
-
-TODO(ianh): Update the timings above to have some relationship to
-reality.
-
-TODO(ianh): Define an API so that the application can adjust the
-budgets.
-
-Task kinds and priorities
--------------------------
-
-Tasks scheduled by futures get the priority and task kind bits from
-the task they are scheduled from.
-
-```dart
-int IdlePriority = 0; // tasks that can be delayed arbitrarily
-int FutureLayoutPriority = 1000; // async-layout tasks
-int AnimationPriority = 3000; // animation-related tasks
-int InputPriority = 4000; // input events
-int ScrollPriority = 5000; // framework-fired events for scrolling
-
-// possible idle queue task bits
-int IdleKind = 0x01; // tasks that should run during the idle loop
-int LayoutKind = 0x02; // tasks that should run during layout
-int TouchSafeKind = 0x04; // tasks that should keep running while there is a pointer down
-int idleTaskBits = IdleKind; // tasks must have all these bits to run during idle loop
-int layoutTaskBits = LayoutKind; // tasks must have all these bits to run during layout
-
-// possible frame queue task bits
-// (there are none at this time)
-int frameTaskBits = 0x00; // tasks must have all these bits to run during the frame loop
-```
diff --git a/specs/script.md b/specs/script.md
deleted file mode 100644
index 4004283159e..00000000000
--- a/specs/script.md
+++ /dev/null
@@ -1,101 +0,0 @@
-Sky Script Language
-===================
-
-The Sky script language is Dart.
-
-The way that Sky integrates the module system with its script language
-is described in [modules.md](modules.md).
-
-All the APIs defined in this documentation, unless explicitly called
-out as being in a framework, are in the `dart:sky` built-in module.
-
-When a method in `dart:sky` defined as ``external`` receives an
-argument, it must type-check it, and, if the argument's value is the
-wrong type, then it must throw an ArgumentError as follows:
-
-   throw new ArgumentError(value, name: name);
-
-...where "name" is the name of the argument. Type checking here
-includes rejecting nulls unless otherwise indicated or unless null is
-argument's default value.
-
-The following definitions are exposed in ``dart:sky``:
-
-```dart
-import 'dart:mirrors';
-
-abstract class AutomaticMetadata {
-  const AutomaticMetadata();
-  void init(DeclarationMirror target, Module module, ScriptElement script);
-
-  static void runLibrary(LibraryMirror library, Module module, ScriptElement script) {
-    library.declarations.values.toList() /* ..sort((DeclarationMirror a, DeclarationMirror b) {
-      bool aHasLocation;
-      try {
-        aHasLocation = a.location != null;
-      } catch(e) {
-        aHasLocation = false;
-      }
-      bool bHasLocation;
-      try {
-        bHasLocation = b.location != null;
-      } catch(e) {
-        bHasLocation = false;
-      }
-      if (!aHasLocation)
-        return bHasLocation ? 1 : 0;
-      if (!bHasLocation)
-        return -1;
-      if (a.location.sourceUri != b.location.sourceUri)
-        return a.location.sourceUri.toString().compareTo(b.location.sourceUri.toString());
-      if (a.location.line != b.location.line)
-        return a.location.line - b.location.line;
-      return a.location.column - b.location.column;
-    }) */
-    ..forEach((DeclarationMirror d) {
-      d.metadata.forEach((InstanceMirror i) {
-        if (i.reflectee is AutomaticMetadata)
-          i.reflectee.run(d, module, script);
-      });
-    });
-  }
-}
-
-class AutomaticFunction extends AutomaticMetadata {
-  const AutomaticFunction();
-  void init(DeclarationMirror target, Module module, ScriptElement script) {
-    assert(target is MethodMirror);
-    MethodMirror f = target as MethodMirror;
-    assert(!f.isAbstract);
-    assert(f.isRegularMethod);
-    assert(f.isTopLevel);
-    assert(f.isStatic);
-    assert(f.parameters.length == 1);
-    assert(f.parameters[0].type == ScriptElement);
-    assert(f.returnType == currentMirrorSystem().voidType);
-    (f.owner as LibraryMirror).invoke(f.simpleName, [script]);
-  }
-}
-const autorun = const AutomaticFunction();
-```
-
-Extensions
-----------
-
-The following as-yet unimplemented features of the Dart language are
-assumed to exist:
-
-* It is assumed that a subclass can define a constructor by reference
-  to a superclass' constructor, wherein the subclass' constructor has
-  the same arguments as the superclass' constructor and does nothing
-  but invoke that superclass' constructor with the same arguments. The
-  syntax for defining this is, within the class body for a class
-  called ClassName:
-
-```dart
-     ClassName = SuperclassName;
-     ClassName.namedConstructor = SuperclassName.otherNamedConstructor;
-```
-
-* The reflection APIs (`dart:mirrors`) are assumed to reflect a
-  library's declarations in source order.
diff --git a/specs/style.md b/specs/style.md
deleted file mode 100644
index 2f878bb844f..00000000000
--- a/specs/style.md
+++ /dev/null
@@ -1,1082 +0,0 @@
-Sky Style Language
-==================
-
-THIS IS NOT UP TO DATE
-
-DO NOT IMPLEMENT THIS YET
-
-It has not been Dartified.
-
-It has not been converted to have a sane element.style API.
-
-It has not been converted to have layout be interruptible using Futures.
-
-
-Planed changes
---------------
-
-Add //-to-end-of-line comments to be consistent with the script
-language.
-
-
-Style Parser
-------------
-
-(this section is incomplete)
-
-### Tokenisation
-
-
-#### Value parser
-
-
-##### **Value** state
-
-If the current character is...
-
-* '``;``': Consume the character and exit the value parser
-  successfully.
-
-* '``@``': Consume the character and switch to the **at**
-  state.
-
-* '``#``': Consume the character and switch to the **hash**
-  state.
-
-* '``$``': Consume the character and switch to the **dollar**
-  state.
-
-* '``%``': Consume the character and switch to the **percent**
-  state.
-
-* '``&``': Consume the character and switch to the **ampersand**
-  state.
-
-* '``'``': Set _value_ to the empty string, consume the character, and
-  switch to the **single-quoted string** state.
-
-* '``"``': Set _value_ to the empty string, consume the character, and
-  switch to the **double-quoted string** state.
-
-* '``-``': Consume the character, and switch to the **negative
-  integer** state.
-
-* '``0``'-'``9``': Set _value_ to the decimal value of the current
-  character, consume the character, and switch to the **integer**
-  state.
-
-* '``a``'-'``z``', '``A``'-'``Z``': Set _value_ to the current
-  character, consume the character, and switch to the **identifier**
-  state.
-
-* '``*``', '``^``', '``!``', '``?``', '``,``', '``/``', '``<``',
-  '``[``', '``)``', '``>``', '``]``', '``+``': Emit a symbol token
-  with the current character as the symbol, consume the character, and
-  stay in this state.
-
-* Anything else: Consume the character and switch to the **error**
-  state.
-
-
-##### **At** state
-
-* '``0``'-'``9``', '``a``'-'``z``', '``A``'-'``Z``': Set _value_ to
-  the current character, create a literal token with the unit set to
-  ``@``, consume the character, and switch to the **literal** state.
-
-* Anything else: Emit a symbol token with ``@`` as the symbol, and
-  switch to the **value** state without consuming the character.
-
-
-##### **Hash** state
-
-* '``0``'-'``9``', '``a``'-'``z``', '``A``'-'``Z``': Set _value_ to
-  the current character, create a literal token with the unit set to
-  ``@``, consume the character, and switch to the **literal** state.
-
-* Anything else: Emit a symbol token with ``#`` as the symbol, and
-  switch to the **value** state without consuming the character.
-
-
-##### **Dollar** state
-
-* '``0``'-'``9``', '``a``'-'``z``', '``A``'-'``Z``': Set _value_ to
-  the current character, create a literal token with the unit set to
-  ``@``, consume the character, and switch to the **literal** state.
-
-* Anything else: Emit a symbol token with ``$`` as the symbol, and
-  switch to the **value** state without consuming the character.
-
-
-##### **Percent** state
-
-* '``0``'-'``9``', '``a``'-'``z``', '``A``'-'``Z``': Set _value_ to
-  the current character, create a literal token with the unit set to
-  ``@``, consume the character, and switch to the **literal** state.
-
-* Anything else: Emit a symbol token with ``%`` as the symbol, and
-  switch to the **value** state without consuming the character.
-
-
-##### **Ampersand** state
-
-* '``0``'-'``9``', '``a``'-'``z``', '``A``'-'``Z``': Set _value_ to
-  the current character, create a literal token with the unit set to
-  ``@``, consume the character, and switch to the **literal** state.
-
-* Anything else: Emit a symbol token with ``&`` as the symbol, and
-  switch to the **value** state without consuming the character.
-
-
-##### TODO(ianh): more states...
-
-
-##### **Error** state
-
-If the current character is...
-
-* '``;``': Consume the character and exit the value parser in failure.
-
-* Anything else: Consume the character and stay in this state.
-
-
-
-Selectors
----------
-
-Sky Style uses whatever SelectorQuery. Maybe one day we'll make
-SelectorQuery support being extended to support arbitrary selectors,
-but for now, it supports:
-
-```css
-tagname
-#id
-.class
-[attrname]
-[attrname=value]
-:host                  ("host" string is fixed)
-::pseudo-element
-```
-
-These can be combined (without whitespace), with at most one tagname
-(must be first) and at most one pseudo-element (must be last) as in:
-
-```css
-tagname[attrname]#id:host.class.class[attrname=value]::foo
-```
-
-In debug mode, giving two IDs, or the same selector twice (e.g. the
-same classname), or specifying other redundant or conflicting
-selectors (e.g. [foo][foo=bar], or [foo=bar][foo=baz]) will be
-flagged.
-
-Alternatively, a selector can be the special value "@root",
-optionally followed by a pseudo-element, as in:
-
-```css
-@root::bar
-```
-
-
-Value Parser
-------------
-
-```javascript
-class StyleToken {
-  constructor (String king, String value);
-  readonly attribute String kind;
-     // string
-     // identifier
-     // function (identifier + '(')
-     // number
-     // symbol (one of @#$%& if not immediately following numeric or preceding alphanumeric, or one of *^!?,/<[)>]+ or, if not followed by a digit, -)
-     // dimension (number + identifier or number + one of @#$%&)
-     // literal (one of @#$%& + alphanumeric)
-  readonly attribute String value;
-  readonly attribute String unit; // for 'dimension' type, this is the punctuation or identifier that follows the number, for 'literal' type, this is the punctuation that precedes it
-}
-
-class TokenSource {
-  constructor (Array<StyleToken> tokens);
-  IteratorResult next();
-  TokenSourceBookmark getBookmark();
-  void rewind(TokenSourceBookmark bookmark);
-}
-
-class TokenSourceBookmark {
-  constructor ();
-  // TokenSource stores unforgeable state on this object using symbols or a weakmap or some such
-}
-
-callback ParserCallback = AbstractStyleValue (TokenSource tokens); // return if successful, throw if not
-
-class StyleGrammar {
-  constructor ();
-  void addParser(ParserCallback parser);
-  AbstractStyleValue parse(TokenSource tokens, Boolean root = false);
-   // for each parser callback that was registered, in reverse
-   // order (most recently registered first), run these steps:
-   //   let bookmark = tokens.getBookmark();
-   //   try { 
-   //     let result = parser(tokens);
-   //     if (root) {
-   //       if (!tokens.next().done)
-   //         throw new Error();
-   //     }
-   //   } except {
-   //     tokens.rewind(bookmark);
-   //   }
-   // (root is set when you need to parse the entire token stream to be valid)
-}
-
-/*
-StyleNode
- |
- +-- Property
- |
- +-- AbstractStyleValue
-     |   
-     +-- NumericStyleValue
-     |    |
-     |    +-- AnimatableNumericStyleValue*
-     |   
-     +-- LengthStyleValue
-     |    |
-     |    +-- AnimatableLengthStyleValue*
-     |    |
-     |    +-- TransitionLengthStyleValue*
-     |    |
-     |    +-- PixelLengthStyleValue
-     |    |
-     |    +-- EmLengthStyleValue*
-     |    |
-     |    +-- VHLengthStyleValue*
-     |    |
-     |    +-- CalcLengthStyleValue*
-     |    
-     +-- ColorStyleValue
-     |    |
-     |    +-- RGBColorStyleValue
-     |    |
-     |    +-- AnimatableColorStyleValue*
-     |    
-     +-- AbstractOpaqueStyleValue
-     |    |
-     |    +-- IdentifierStyleValue
-     |    |    |
-     |    |    +-- AnimatableIdentifierStyleValue*
-     |    |    
-     |    +-- URLStyleValue*
-     |    |    |
-     |    |    +-- AnimatableURLStyleValue*
-     |    |    
-     |    +-- StringStyleValue*
-     |    |    |
-     |    |    +-- AnimatableStringStyleValue*
-     |    |    
-     |    +-- ObjectStyleValue
-     |    
-     +-- PrimitiveValuesListStyleValue*
-*/
-```
-
-The types marked with * in the list above are not part of dart:sky,
-and are only shown here to illustrate what kinds of extensions are
-possible and where they would fit.
-
-TODO(ianh): consider removing 'StyleValue' from these class names
-
-```javascript
-abstract class StyleNode {
-  abstract void markDirty();
-}
-
-dictionary StyleValueResolverSettingsSettings {
-  Boolean firstTime = false;
-  any state = null;
-}
-
-class StyleValueResolverSettings {
-  // this is used as an "out" parameter for 'resolve()' below
-  constructor(StyleValueResolverSettingsSettings initial);
-  void reset(StyleValueResolverSettingsSettings initial);
-    // sets firstTime and state to given values
-    // sets layoutDependent to false
-    // sets dependencies to empty set
-    // sets lifetime to Infinity
-
-  readonly attribute Boolean firstTime;
-    // true if this is the first time this property is being resolved for this element,
-    // or if the last time it was resolved, the value was a different object
-
-  // attribute Boolean layoutDependent
-  void setLayoutDependent();
-    // call this if the value should be recomputed each time the ownerLayoutManager's dimensions change, rather than being cached
-  Boolean getLayoutDependent();
-    // returns true if setLayoutDependent has been called since the last reset()
-
-  // attribute "BitField" dependencies; // defaults to no bits set
-  void dependsOn(PropertyHandle property);
-    // if the given property doesn't have a dependency bit assigned:
-    //  - assign the next bit to the property
-    //  - if there's no bits left, throw
-    // set the bit on this StyleValueResolverSettings's dependencies bitfield
-  Array<PropertyHandle> getDependencies();
-    // returns an array of the PropertyHandle values for the bits that are set in dependencies
-
-  // attribute (Float or Infinity) lifetime;
-  void setLifetime(Float age);
-    // if the new value is less than the current value of lifetime, update the current value
-  (Float or Infinity) getLifetime();
-    // return current value of lfietime
-
-  attribute any state; // initially null, can be set to store value for this RenderNode/property pair
-    // for example, TransitioningColorStyleValue would store
-    //    {
-    //      initial: /* color at time of transition */,
-    //      target: /* color at end of transition */,
-    //      start: /* time at start of transition */,
-    //    }
-    // ...which would enable it to update appropriately, and would also
-    // let other transitions that come later know that you were half-way
-    // through a transition so they can shorten their time accordingly
-    //
-    // best practices: if you're storing values on the state object,
-    // then remove the values once they are no longer needed. For
-    // example, when your transition ends, set the object to null.
-    //
-    // best practices: if you're a style value that contains multiple
-    // style values, then before you call their resolve you should
-    // replace the state with a state that is specific to them, and
-    // when you get it back you should insert that value into your
-    // state somehow. For example, in a resolve()r with two child
-    // style values a and b:
-    //    let ourState;
-    //    if (settings.firstTime)
-    //      ourState = { a: null, b: null };
-    //    else
-    //      ourState = settings.state;
-    //    settings.state = ourState.a;
-    //    let aResult = a.resolve(node, settings);
-    //    ourState.a = settings.state;
-    //    settings.state = ourState.b;
-    //    let aResult = b.resolve(node, settings);
-    //    ourState.b = settings.state;
-    //    settings.state = ourState;
-    //    return a + b; // or whatever
-    //
-    // best practices: if you're a style value that contains multiple
-    // style values, and all those style values are storing null, then
-    // store null yourself, instead of storing many nulls of your own.
-
-  // attribute Boolean wasStateSet;
-  Boolean getShouldSaveState();
-    // returns true if state is not null, and either state was set
-    // since the last reset, or firstTime is false.
-
-}
-
-class Property : StyleNode {
-  constructor (AbstractStyleDeclaration parentNode, PropertyHandle property, AbstractStyleValue? initialValue = null);
-  readonly attribute AbstractStyleDeclaration parentNode;
-  readonly attribute PropertyHandle property;
-  readonly attribute AbstractStyleValue value;
-
-  void setValue(AbstractStyleValue? newValue);
-    // updates value and calls markDirty()
-
-  void markDirty();
-    // call parentNode.markDirty(property);
-
-  abstract any resolve(RenderNode node, StyleValueResolverSettings? settings = null);
-    // if value is null, returns null
-    // otherwise, returns value.resolve(property, node, settings)
-}
-
-abstract class AbstractStyleValue : StyleNode {
-  abstract constructor(StyleNode? parentNode = null);
-  attribute StyleNode? parentNode;
-
-  void markDirty();
-    // call this.parentNode.markDirty()
-
-  abstract any resolve(PropertyHandle property, RenderNode node, StyleValueResolverSettings? settings = null);
-}
-
-abstract class LengthStyleValue : AbstractStyleValue {
-  abstract Float resolve(PropertyHandle property, RenderNode node, StyleValueResolverSettings? settings = null);
-}
-
-class PixelLengthStyleValue : LengthStyleValue {
-  constructor(Float number, StyleNode? parentNode = null);
-  attribute Float value;
-    // on setting, calls markDirty();
-  Float resolve(PropertyHandle property, RenderNode node, StyleValueResolverSettings? settings = null);
-    // return value
-}
-
-typedef RawColor Float; // TODO(ianh): figure out what Color should be
-class ColorStyleValue : LengthStyleValue {
-  constructor(Float red, Float green, Float blue, Float alpha, StyleNode? parentNode = null);
-  // ... color API ...
-  RawColor resolve(PropertyHandle property, RenderNode node, StyleValueResolverSettings? settings = null);
-}
-
-class AbstractOpaqueStyleValue : AbstractStyleValue {
-  abstract constructor(any value, StyleNode? parentNode = null);
-  attribute any value;
-    // on setting, calls markDirty();
-  any resolve(PropertyHandle property, RenderNode node, StyleValueResolverSettings? settings = null);
-    // returns value
-}
-
-class IdentifierStyleValue : AbstractOpaqueStyleValue {
-  constructor(String value, StyleNode? parentNode = null);
-    // calls superclass constructor
-}
-
-/*
-class AnimatableIdentifierStyleValue : AbstractOpaqueStyleValue {
-  constructor(String value, String newValue, AnimationFunction player, StyleNode? parentNode = null);
-  readonly attribute String newValue;
-  readonly attribute AnimationFunction player;
-  any resolve(PropertyHandle property, RenderNode node, StyleValueResolverSettings? settings = null);
-}
-*/
-
-class ObjectStyleValue : AbstractOpaqueStyleValue {
-  constructor(any value, StyleNode? parentNode = null);
-    // calls superclass constructor
-}
-
-dictionary PropertySettings {
-  String? name = null; // null if the property can't be set from a <style> block
-  StyleGrammar? grammar = null; // must be non-null if name is non-null; must be null otherwise
-  Boolean inherited = false;
-  any initialValue = null;
-  Boolean needsManager = false;
-  Boolean needsLayout = false;
-  Boolean needsPaint = false;
-  // PropertyHandle propertyHandle; // assigned by registerProperty
-  // Integer dependencyBit; // assigned by StyleValueResolverSettings.dependsOn()
-}
-typedef PropertyHandle Integer;
-PropertyHandle registerProperty(PropertySettings propertySettings);
-  // registers a property with the given settings, and returns an integer >= 0
-  // that can be used to refer to this property
-
-// dart:sky exports a bunch of style grammars so that people can extend them
-attribute StyleGrammar PositiveLengthOrInfinityStyleGrammar; // resolves to LengthStyleValue
-attribute StyleGrammar PositiveLengthOrAutoStyleGrammar; // resolves to LengthStyleValue or IdentifierStyleValue (with value 'auto')
-attribute StyleGrammar PositiveLengthStyleGrammar; // resolves to LengthStyleValue
-attribute StyleGrammar NumberGrammar; // resolves to NumericStyleValue
-attribute StyleGrammar ColorGrammar; // resolves to ColorStyleValue
-attribute StyleGrammar DisplayStyleGrammar; // resolves to ObjectStyleValue
-```  
-
-Inline Styles
--------------
-
-```javascript
-abstract class AbstractStyleDeclarationList {
-  void addStyles(StyleDeclaration styles, String pseudoElement = ''); // O(1)
-  void removeStyles(StyleDeclaration styles, String pseudoElement = ''); // O(N) in number of declarations
-  Array<StyleDeclaration> getDeclarations(String pseudoElement = ''); // O(N) in number of declarations
-}
-
-class ElementStyleDeclarationList : AbstractStyleDeclarationList {
-  constructor (Element? element);
-  readonly attribute Element? element;
-
-  // there are two batches of styles in an ElementStyleDeclarationList.
-
-  // the first batch is the per-frame styles; these get (conceptually)
-  // cleared each frame, after which all the matching rules in relevant
-  // <style> blocks get added back in, followed by all the animation-
-  // derived rules; scripts can also add styles themselves, but they are
-  // dropped after the next frame
-  void addFrameStyles(StyleDeclaration styles, String pseudoElement = ''); // O(1)
-  void clearFrameStyles();
-
-  // the second batch is the persistent styles, which remain until removed;
-  // they are accessed via the AbstractStyleDeclarationList accessors
-
-  // as StyleDeclarations are added and removed, the ElementStyleDeclarationList
-  // calls register(element) and unregister(element) respectively on those
-  // StyleDeclaration objects, where element is the element that was passed
-  // to the constructor, if not null
-  // then, it calls element.renderNode.cascadedValueChanged
-  // for each property on the object
-
-  // the inherited getDeclarations() method returns all the frame
-  // styles followed by all the persistent styles, in insertion order
-}
-
-class RenderNodeStyleDeclarationList : AbstractStyleDeclarationList {
-  constructor (RenderNode? renderNode);
-  readonly attribute RenderNode? renderNode;
-
-  // as StyleDeclarations are added and removed, the RenderNodeStyleDeclarationList
-  // calls register(renderNode) and unregister(renderNode) respectively on those
-  // StyleDeclaration objects, where renderNode is the RenderNode that was passed
-  // to the constructor, if not null
-  // then, it calls renderNode.cascadedValueChanged
-  // for each property on the object
-}
-
-class StyleDeclaration {
-  constructor ();
-
-  void markDirty(PropertyHandle property);
-    // this indicates that the cascaded value of the property thinks
-    // it will now have a different result (as opposed to the cascaded
-    // value itself having changed)
-    // invoke element.renderNode.cascadedValueDirty(property, pseudoElement); for each
-    // currently registered consumer element/pseudoElement pair
-
-  void register((Element or RenderNode) consumer, String pseudoElement = ''); // O(1)
-  void unregister((Element or RenderNode) consumer, String pseudoElement = ''); // O(N)
-    // registers an element/pseudoElement or renderNode/pseudoElement pair with
-    // this StyleDeclaration so that a property/value on the style declaration
-    // is marked dirty, the relevant render node is informed and can then update
-    // its property cache accordingly
-
-
-  getter AbstractStyleValue? (PropertyHandle property);
-    // looks up the Property object for /property/, and returns its value
-    // null if property is missing
-
-  setter void (PropertyHandle property, AbstractStyleValue value);
-    // verify that value.parentNode is null
-    // if there is no Property object for /property/, creates one
-    // else calls its update() method to change the value
-    // update value's parentNode
-    // invoke consumer.renderNode.cascadedValueChanged(property); for each
-    // currently registered consumer
-
-  void remove(PropertyHandle property);
-    // drops the Property object for /property/ from this StyleDeclaration object
-    // invoke consumer.renderNode.cascadedValueChanged(property); for each
-    // currently registered consumer
-}
-```
-
-Rule Matching
--------------
-
-```javascript
-class Rule {
-  constructor ();
-  attribute SelectorQuery selector; // O(1)
-  attribute String pseudoElement; // O(1)
-  attribute StyleDeclaration styles; // O(1)
-}
-```
-
-Each frame, at some defined point relative to requestAnimationFrame(),
-if a Rule has started applying, or a Rule stopped applying, to an
-element, dart:sky calls thatElement.style.clearFrameStyles() and then,
-for each Rule that now applies, calls
-thatElement.style.addFrameStyles() with the relevant StyleDeclaration
-and pseudoElement from each such Rule.
-
-
-Update the render tree
-----------------------
-
-Simultaneously walk the tree rooted at the application's element
-tree's root node, taking into account shadow trees and child
-distribution, and the tree rooted at that Root node's RenderNode.
-
-If you come across a node that doesn't have an assigned RenderNode,
-then create one, placing it in the appropriate place in the RenderTree
-tree, after any nodes marked isGhost=true, with ownerLayoutManager
-pointing to the parent RenderNode's layoutManager, if it has one, and,
-if it has one and autoreap is false on that layout manager, mark the
-new node "isNew". (This means that when a node is marked isNew, the
-layout manager has already laid out at least one frame.)
-
-For each element, if the node's needsManager is true, call
-getLayoutManager() on the element, and if that's not null, and if the
-returned class isn't the same class as the current layoutManager, if
-any, construct the given class and assign it to the RenderNode's
-layoutManager, then set all the child RenderNodes' ownerLayoutManager
-to that object; if it returns null, and that node already has a
-layoutManager, then set isGhost=true for that node and all its
-children (without changing the layoutManager). Otherwise, if it
-returned null and there's already no layoutManager, remove the node
-from the tree. Then, in any case, clear the needsManager bit.
-
-When an Element or Text node is to be removed from its parent, and it
-has a renderNode, and that renderNode has an ownerLayoutManager with
-autoreap=false, then before actually removing the node, the node's
-renderNode should be marked isGhost=true, and all the
-StyleDeclarations in the relevant ElementStyleDeclarationList should
-be added to the RenderNode's overrideStyles for use later (creating a
-RenderNodeStyleDeclarationList if necessary).
-
-When an Element is to be removed from its parent, regardless of the
-above, the node's renderNode attribute should be nulled out.
-
-When a RenderNode is added with isNew=true, call its parent
-RenderNode's LayoutManager's childAdded() callback. When a a
-RenderNode has its isGhost property set to true, then call it's parent
-RenderNode's LayoutManager's childRemoved() callback.
-
-
-```javascript
-dictionary PropertySettings {
-  String? name = null; // null if the property can't be set from a <style> block
-  StyleGrammar? grammar = null; // must be non-null if name is non-null; must be null otherwise
-  Boolean inherited = false;
-  any initialValue = null;
-  Boolean needsManager = false;
-  Boolean needsLayout = false;
-  Boolean needsPaint = false;
-  // PropertyHandle propertyHandle; // assigned by registerProperty
-  // Integer dependencyBit; // assigned by StyleValueResolverSettings.dependsOn()
-}
-
-dictionary GetPropertySettings {
-  String pseudoElement = '';
-  Boolean forceCache = false;
-    // if set to true, will return the cached value if any, or null otherwise
-    // this is used by transitions to figure out what to transition from
-}
-
-class RenderNode { // implemented in C++ with no virtual tables
-  // this is generated before layout
-  readonly attribute String text;
-  readonly attribute Node? parentNode;
-  readonly attribute Node? firstChild;
-  readonly attribute Node? nextSibling;
-
-  // internal state:
-  // - back pointer to backing Node, if we're not a ghost
-  // - cache of resolved property values, mapping as follows:
-  //    - pseudoElement, property => StyleValue object, resolved value, StyleValueResolverSettings, cascade dirty bit, value dirty bit
-  // - property state map (initially empty), as follows:
-  //    - pseudoElement, property => object
-
-  any getProperty(PropertyHandle property, GetPropertySettings? settings = null);
-     // looking at the cached data for the given pseudoElement:
-     // if there's a cached value:
-     //   if settings.forceCache is true, return the cached value
-     //   if neither dirty bit is set, return the cached value
-     //   if the cascade dirty bit is not set (value dirty is set) then
-     //    - clear any pending lifetime-enforcing tasks for this
-     //      property/pseudoElement pair on this render node
-     //    - resolve the value using the same StyleValue object
-     //       - with firstTime=false on the resolver settings
-     //       - with the cached state object if any
-     //       - jump to "cache" below
-     // if settings.forceCache is true, return null
-     // - clear any pending lifetime-enforcing tasks for this
-     //   property/pseudoElement pair on this render node
-     // - if there's an override declaration with the property (with
-     //   the pseudo or without), then get the value object from there
-     //   and jump to "resolve" below.
-     // - if there's an element and it has a style declaration with
-     //   the property (with the pseudo or without), then get the
-     //   value object from there and jump to "resolve" below.
-     // - if it's not an inherited property, or if there's no parent,
-     //   then get the default value and jump to "resolve" below.
-     // - call the parent render node's getProperty() with the same
-     //   property but no settings, then cache that value as the value
-     //   for this element with the given pseudoElement, with no
-     //   StyleValue object, no resolver settings, and set the state
-     //   to null.
-     // resolve:
-     //   - get a new resolver settings object (or reset an existing one)
-     //     - if the obtained StyleValue object is different than the
-     //       cached StyleValue object, or if there is no cached
-     //       object, then set the resolver settings to
-     //       firstTime=true, otherwise it's the same object and set
-     //       firstTime=false.
-     //     - set the resolver settings' state to the current state
-     //       for this pseudoElement/property combination
-     //   - using the obtained StyleValue object, call resolve(),
-     //     passing it this node and the resolver settings object.
-     //   - jump to "cache" below
-     // cache:
-     //   - update the cache with the obtained value and resolver
-     //     settings
-     //   - reset the dirty bits
-     //   - if the resolver settings' getShouldSaveState() method
-     //     returns false, then discard any cached state, otherwise,
-     //     cache the new state
-     //   - if the resolver settings' lifetime is not infinity, then
-     //     queue a lifetime-enforcing task for the appropriate time
-     //     in the future which calls cascadedValueDirty for this
-     //     property/pseudoElement pair on this render node
-
-  attribute RenderNodeStyleDeclarationList overrideStyles;
-     // mutable; initially null
-     // this is used when isGhost is true, and can also be used more generally to
-     // override styles from the layout manager (e.g. to animate a new node into view)  
-     // this is the only arbitrarily mutable state of a RenderNode object
-
-  private void cascadedValueChanged(PropertyHandle property, String pseudoElement = '');
-  private void cascadedValueDirty(PropertyHandle property, String pseudoElement = '');
-    // - set the appropriate dirty bit on the cached data for this property/pseudoElement pair
-    //    - cascade dirty for cascadedValueChanged
-    //    - value dirty for cascadedValueDirty
-    // - if the property is needsManager, set needsManager to true
-    // - if the property is needsLayout, set needsLayout to true and walk up the
-    //   tree setting descendantNeedsLayout
-    // - if the property is needsPaint, add the node to the list of nodes that need painting
-    // - if the property has a dependencyBit defined, then check the cache of all the
-    //   properties on this RenderNode, and the cache for the property in all the child
-    //   nodes and, if pseudoElement is '', the pseudoElements of this node, and,
-    //   if any of them have the relevant dependency bit set, then call
-    //     thatRenderNode.cascadedValueDirty(thatProperty, thatPseudoElement)
-    // - if the property is inherited, then for each child node, and, if pseudoElement
-    //   is '', the pseudoElements of this node, if the cached value for this property
-    //   is present but has no StyleValue, call thatNode.cascadedValueChanged(property, thatPseudoElement)
-
-  readonly attribute Boolean needsManager;
-    // means that a property with needsManager:true has changed on this node
-
-  readonly attribute Boolean needsLayout;
-    // means that either needsManager is true or a property with needsLayout:true has changed on this node
-    // needsLayout is set to false by the ownerLayoutManager's default layout() method
-
-  readonly attribute Boolean descendantNeedsLayout;
-    // means that some child of this node has needsLayout set to true
-    // descendantNeedsLayout is set to false by the ownerLayoutManager's default layout() method
-
-  readonly attribute LayoutManager layoutManager;
-  readonly attribute LayoutManager ownerLayoutManager; // defaults to the parentNode.layoutManager
-    // if you are not the ownerLayoutManager, then ignore this RenderNode in layout() and paintChildren()
-    // using walkChildren() does this for you
-
-  // only the ownerLayoutManager can change these
-  readonly attribute Float x; // relative to left edge of ownerLayoutManager
-  readonly attribute Float y; // relative to top edge of ownerLayoutManager
-  readonly attribute Float width;
-  readonly attribute Float height;
-  readonly attribute Boolean isNew; // node has just been added (and maybe you want to animate it in)
-  readonly attribute Boolean isGhost; // node has just been removed (and maybe you want to animate it away)
-}
-```
-
-The flattened tree is represented as a hierarchy of Node objects. For
-any element that only contains text node children, the "text" property
-is set accordingly. For elements with mixed text node and non-text
-node children, each run of text nodes is represented as a separate
-Node with the "text" property set accordingly and the styles set as if
-the Node inherited everything inheritable from its parent.
-
-
-Layout
-------
-
-dart:sky registers 'display' as follows:
-
-```javascript
-  {
-    name: 'display',
-    grammar: sky.DisplayStyleGrammar,
-    inherited: false,
-    initialValue: sky.BlockLayoutManager,
-    needsManager: true,
-  }
-```
-
-The following API is then used to add new layout manager types to 'display':
-
-```javascript
-void registerLayoutManager(String displayValue, LayoutManagerConstructor? layoutManager);
-```
-
-dart:sky by default registers:
-
-- 'block': sky.BlockLayoutManager
-- 'paragraph': sky.ParagraphLayoutManager
-- 'inline': sky.InlineLayoutManager
-- 'none': null
-
-
-Layout managers inherit from the following API:
-
-```javascript
-callback LayoutManagerConstructor LayoutManager (RenderNode node);
-
-class LayoutManager : EventTarget {
-  readonly attribute RenderNode node;
-  constructor LayoutManager(RenderNode node);
-    // sets needsManager to false on the node
-
-  readonly attribute Boolean autoreap;
-    // defaults to true
-    // when true, children that are added don't get set to isNew=true
-    // when true, children that are removed don't get set to isGhost=true, they're just removed
-
-  virtual Array<EventTarget> getEventDispatchChain(); // O(N) in number of this.node's ancestors // implements EventTarget.getEventDispatchChain()
-    // let result = [];
-    // let node = this.node;
-    // while (node && node.layoutManager) {
-    //   result.push(node.layoutManager);
-    //   node = node.parentNode;
-    // }
-    // return result;
-
-  void setProperty(RenderNode node, PropertyHandle property, any value, String pseudoElement = ''); // O(1)
-    // replaces the value that getProperty() would return on that node with /value/
-    // this also clears the dependency bits, dirty bits, and sets the property state to null
-    // this also clears any relevant lifetime-enforcing tasks
-
-  void take(RenderNode victim); // sets victim.ownerLayoutManager = this;
-    // assert: victim hasn't been take()n yet during this layout
-    // assert: an ancestor of victim has node.layoutManager == this (aka, victim is a descendant of this.node)
-
-  virtual void release(RenderNode victim);
-    // called when the RenderNode was removed from the tree
-
-  virtual void childAdded(RenderNode child);
-  virtual void childRemoved(RenderNode child);
-    // called when a child has its isNew or isGhost attributes set respectively
-
-  void setChildPosition(child, x, y); // sets child.x, child.y
-  void setChildX(child, y); // sets child.x
-  void setChildY(child, y); // sets child.y
-  void setChildSize(child, width, height); // sets child.width, child.height
-  void setChildWidth(child, width); // sets child.width
-  void setChildHeight(child, height); // sets child.height
-    // assert: child.ownerLayoutManager == this
-    // for setChildSize/Width/Height: if the new dimension is different than the last assumed dimensions, and
-    // any RenderNodes with an ownerLayoutManager==this have cached values for getProperty() that are marked
-    // as layout-dependent, mark them as dirty with cascadedValueDirty()
-
-  void assumeDimensions(Float width, Float height);
-    // sets the assumed dimensions for calls to getProperty() on RenderNodes that have this as an ownerLayoutManager,
-    // by updating renderNode width/height;
-    // if the new dimension is different than the last assumed dimensions, and any RenderNodes with an
-    // ownerLayoutManager==this have cached values for getProperty() that are marked as layout-dependent, mark them
-    // as dirty with cascadedValueDirty()
-
-  virtual LayoutValueRange getIntrinsicWidth(Float? defaultWidth = null);
-  /*
-     function getIntrinsicWidth(defaultWidth) {
-       if (defaultWidth == null) {
-         defaultWidth = this.node.getProperty('width');
-         if (typeof defaultWidth != 'number')
-           defaultWidth = 0;
-       }
-       let minWidth = this.node.getProperty('min-width');
-       if (typeof minWidth != 'number')
-         minWidth = 0;
-       let maxWidth = this.node.getProperty('max-width');
-       if (typeof maxWidth != 'number')
-         maxWidth = Infinity;
-       if (maxWidth < minWidth)
-         maxWidth = minWidth;
-       if (defaultWidth > maxWidth)
-         defaultWidth = maxWidth;
-       if (defaultWidth < minWidth)
-         defaultWidth = minWidth;
-       return {
-         minimum: minWidth,
-         value: defaultWidth,
-         maximum: maxWidth,
-       };
-     }
-  */
-
-  virtual LayoutValueRange getIntrinsicHeight(Float? defaultHeight = null);
-  /*
-     function getIntrinsicHeight(defaultHeight) {
-       if (defaultHeight == null) {
-         defaultHeight = this.node.getProperty('height');
-         if (typeof defaultHeight != 'number')
-           defaultHeight = 0;
-       }
-       let minHeight = this.node.getProperty('min-height');
-       if (typeof minHeight != 'number')
-         minHeight = 0;
-       let maxHeight = this.node.getProperty('max-height');
-       if (typeof maxHeight != 'number')
-         maxHeight = Infinity;
-       if (maxHeight < minHeight)
-         maxHeight = minHeight;
-       if (defaultHeight > maxHeight)
-         defaultHeight = maxHeight;
-       if (defaultHeight < minHeight)
-         defaultHeight = minHeight;
-       return {
-         minimum: minHeight,
-         value: defaultHeight,
-         maximum: maxHeight,
-       };
-     }
-  */
-
-  void welcomeChild(child);
-    // assert: this == child.ownerLayoutManager
-    // assert: child.isNew is true
-    // resets child.isNew
-  void reapChild(child);
-    // assert: this == child.ownerLayoutManager
-    // assert: child.isGhost is true
-    // removes the RenderNode from its parent if isGhost is true
-
-  Generator<RenderNode> walkChildren();
-    // returns a generator that iterates over the children, skipping any whose ownerLayoutManager is not |this|
-
-  Generator<RenderNode> walkChildrenBackwards();
-    // returns a generator that iterates over the children backwards, skipping any whose ownerLayoutManager is not |this|
-
-  void markAsLaidOut(); // sets this.node.needsLayout and this.node.descendantNeedsLayout to false
-  virtual Dimensions layout(Float? width, Float? height);
-    // if width is null, set width to getIntrinsicWidth().value
-    // if height is null, set height to getIntrinsicHeight().value
-    // call this.assumeDimensions(width, height);
-    // call this.layoutChildren(width, height);
-    // call markAsLaidOut();
-    // return { width: width, height: height }
-    // - this should always call this.markAsLaidOut() to reset
-    //   needsLayout and descendantNeedsLayout
-    // - the return value should include the final value for whichever
-    //   of the width and height arguments that is null
-    // - subclasses that want to make 'auto' values dependent on the
-    //   children should override this entirely, rather than
-    //   overriding layoutChildren; but see layoutChildren()'s notes
-    //   for how to do this
-
-  virtual void layoutChildren(Float width, Float height);
-    // default implementation does nothing
-    // - override only this (and not layout()) if you want to lay out
-    //   children but not have the children affect your dimensions
-    // - always call setChildSize() and setChildPosition() after
-    //   calling a child's layout() method
-    // - if the child has needsLayout or if you need to have it
-    //   autosize, call its ownerLayoutManager's layout() method
-    // - otherwise if the child has needs descendantNeedsLayout, call
-    //   layoutDescendants()
-
-  virtual Dimensions layoutDescendants();
-    // assert: node.needsLayout is false, node.descendantNeedsLayout is true
-    // walk children:
-    //  - if it has needsLayout, call its layout() method with its
-    //    current width and height, then call setChildSize() with
-    //    those same dimensions
-    //  - else, if it has descendantNeedsLayout, call its
-    //    layoutDescendants() method
-    // call markAsLaidOut();
-    // - override this if you use take() to control more children, in
-    //   which case you should call their methods too
-    // - this should always call this.markAsLaidOut() to reset
-    //   needsLayout and descendantNeedsLayout
-
-  virtual void paint(RenderingSurface canvas);
-    // set a clip rect on the canvas for rect(0,0,this.width,this.height)
-    //   (? we don't really have to do this; consider shadows...)
-    // call this.paintChildren(canvas)
-    // (the default implementation doesn't paint anything on top of the children)
-    // unset the clip
-    // - this gets called by the system if:
-    //    - you are in your parent's current display list and it's in its parent's and so on up to the top, and
-    //    - you haven't had paint() called since the last time you were dirtied
-    // - the following things make you dirty:
-    //    - dimensions of your RenderNode changed
-    //    - one of your properties with needsLayout or needsPaint changed
-
-  virtual void paintChildren(RenderingSurface canvas);
-    // for each child returned by walkChildren():
-    //   if child bounds intersects our bounds:
-    //     call canvas.paintChild(child);
-    // - you should skip children that will be clipped out of yourself because they're outside your bounds
-    // - if you transform the canvas, you'll have to implement your own version of paintChildren() so
-    //   that you don't skip the children that are visible in the new coordinate space but wouldn't be
-    //   without the transform
-
-  virtual RenderNode hitTest(Float x, Float y);
-    // default implementation uses the node's children nodes' x, y,
-    // width, and height, skipping any that have width=0 or height=0, or
-    // whose ownerLayoutManager is not |this|
-    // default implementation walks the tree backwards from its built-in order
-    // if no child is hit, then return this.node
-    // override this if you changed your children's z-order, or if you used take() to
-    // hoist some descendants up to be your responsibility, or if your children aren't
-    // rectangular (e.g. you lay them out in a hex grid)
-    // make sure to offset the value you pass your children: child.layoutManager.hitTest(x-child.x, y-child.y)
-}
-
-dictionary LayoutValueRange {
-  // negative values here should be treated as zero
-  Float minimum = 0;
-  Float value = 0; // ideal desired width; if it's not in the range minimum .. maximum then it overrides minimum and maximum
-  (Float or Infinity) maximum = Infinity; 
-}
-
-dictionary Dimensions {
-  Float width = 0;
-  Float height = 0;
-}
-```
-
-
-Paint
------
-
-Sky has a list of RenderNodes that need painting. When a RenderNode is
-created, it's added to this list. (See also needsPaint for another
-time it is added to the list.)
-
-```javascript
-callback void Painter (RenderNode node, RenderingSurface canvas);
-
-class RenderingSurface {
-
-  // ... (API similar to <canvas>'s 2D API)
-
-  void paintChild(RenderNode node);
-    // inserts a "paint this child" instruction in this canvas's display list.
-    // the child's display list, transformed by the child's x and y coordinates, will be inserted into this
-    // display list during painting.
-}
-```
-
-
-The default framework provides global hooks for extending the painting of:
-
- - borders
- - backgrounds
-
-These are called during the default framework's layout managers'
-paint() functions. They are also made available so that other people
-can call them from their paint() functions.
-
-
-
-Default Styles
---------------
-
-In the constructors for the default elements, they add to themselves
-StyleDeclaration objects as follows:
-
-* ``span``
-* ``a``
-  These all add to themselves the same declaration as follows:
-```javascript
-let d = new StyleDeclaration();
-d[pDisplay] = new ObjectStyleValue(InlineLayoutManager);
-this.style.addStyles(d);
-```
-
-* ``t``
-  This adds to itself the declaration as follows:
-```javascript
-let d = new StyleDeclaration();
-d[pDisplay] = new ObjectStyleValue(ParagraphLayoutManager);
-this.style.addStyles(d);
-```
-
-The other elements don't have any default styles.
-
-These declarations are all shared between all the elements (so e.g. if
-you reach in and change the declaration that was added to a ``span``
-element, you're going to change the styles of all the other
-default-hidden elements). (In other words, in the code snippets above,
-the ``d`` variable is initialised in shared code, and only the
-addStyles() call is per-element.)
diff --git a/specs/style2.md b/specs/style2.md
deleted file mode 100644
index 1a2cec2db3c..00000000000
--- a/specs/style2.md
+++ /dev/null
@@ -1,348 +0,0 @@
-Sky Style Language
-==================
-
-This is a trimmed down version of the API in (style.md)[style.md]
-that is intended to be a stepping stone to the long-term world where
-there are no hard-coded properties in the engine.
-
-The Sky style API looks like the following:
-
-```dart
-
-  // all properties can be set as strings:
-  element.style['color'] = 'blue';
-
-  // some properties have dedicated APIs
-  // color
-  element.style.color.red += 1; // 0..255
-  element.style.color.blue += 10; // 0..255
-  element.style.color.green = 255; // 0..255
-  element.style.color.alpha = 128; // 0..255
-  // transform
-  element.style.transform..reset()
-                         ..translate(100, 100)
-                         ..rotate(PI/8)
-                         ..translate(-100, -100);
-  element.style.transform.translate(10, 0);
-  // height, width
-  element.style.height.auto = true;
-  if (element.style.height.auto)
-    element.style.height.pixels = 10;
-  element.style.height.pixels += 1;
-  element.style.height.em = 1;
-
-  // each property with a dedicated API defines a shorthand setter
-  // style.transform takes a matrix:
-  element.style.transform = new Matrix(1.0, 0.0, 0.0, 1.0, 0.0, 0.0);
-  // style.color takes a 32bit int:
-  element.style.color = 0xFF009900;
-  // style.height and style.width takes pixels or the constant 'auto':
-  element.style.height = auto;
-  element.style.width = 100;
-  // all properties with a dedicated API can also be set to null, inherit, or initial:
-  element.style.transform = null; // unset the property
-  element.style.color = initial; // set it to its initial value
-  element.style.color = inherit; // make it get its parent's value
-
-  // you can create a blank StyleDeclaration object:
-  var style = new StyleDeclaration();
-  // you can replace an element's StyleDeclaration object wholesale:
-  element.style = style;
-  // you can clone a StyleDeclaration object:
-  var style2 = new StyleDeclaration.clone(style);
-```
-
-The dart:sky library contains the following to define this API:
-
-```dart
-import 'dart:mirrors';
-import 'dart:math';
-
-typedef void StringSetter(Symbol propertySymbol, StyleDeclaration declaration, String value);
-typedef String StringGetter(Symbol propertySymbol, StyleDeclaration declaration);
-typedef Property ObjectConstructor(Symbol propertySymbol, StyleDeclaration declaration);
-
-class PropertyTable {
-  const PropertyTable({this.symbol, this.inherited, this.stringGetter, this.stringSetter, this.objectConstructor});
-  final Symbol symbol;
-  final bool inherited;
-  final StringSetter stringSetter;
-  final StringGetter stringGetter;
-  final ObjectConstructor objectConstructor;
-}
-
-Map<Symbol, PropertyTable> _registeredProperties = new Map<Symbol, PropertyTable>();
-void registerProperty(PropertyTable data) {
-  assert(data.symbol is Symbol);
-  assert(data.inherited is bool);
-  assert(data.stringSetter is StringSetter);
-  assert(data.stringGetter is StringGetter);
-  assert(data.objectConstructor == null || data.objectConstructor is ObjectConstructor);
-  assert(!_registeredProperties.containsKey(data.symbol));
-  _registeredProperties[data.symbol] = data;
-}
-
-@proxy
-class StyleDeclaration {
-  StyleDeclaration() { this._init(); }
-  StyleDeclaration.clone(StyleDeclaration template) { this.init(template); }
-  external void _init([StyleDeclaration template]); // O(1)
-  // This class has C++-backed internal state representing the
-  // properties known to the system. It's assumed that Property
-  // subclasses are also C++-backed and can directly manipulate this
-  // internal state.
-  // If the argument 'template' is provided, then this should be a clone
-  // of the styles of the template StyleDeclaration
-
-  operator [](String propertyName) {
-    var propertySymbol = new Symbol(propertyName);
-    if (_registeredProperties.containsKey(propertySymbol))
-      return _registeredProperties[propertySymbol].stringGetter(propertySymbol, this);
-    throw new ArgumentError(propertyName);
-  }
-
-  operator []=(String propertyName, String newValue) {
-    var propertySymbol = new Symbol(propertyName);
-    if (_registeredProperties.containsKey(propertySymbol))
-      return _registeredProperties[propertySymbol].stringSetter(propertySymbol, this, newValue);
-    throw new ArgumentError(propertyName);
-  }
-
-  // some properties expose dedicated APIs so you don't have to use string manipulation
-  MapOfWeakReferences<Symbol, Property> _properties = new MapOfWeakReferences<Symbol, Property>();
-  noSuchMethod(Invocation invocation) {
-    Symbol propertySymbol;
-    if (invocation.isSetter) {
-      // when it's a setter, the name will be "foo=" rather than "foo"
-      String propertyName = MirrorSystem.getName(invocation.memberName);
-      assert(propertyName[propertyName.length-1] == '=');
-      propertySymbol = new Symbol(propertyName.substring(0, propertyName.length-1));
-    } else {
-      propertySymbol = invocation.memberName;
-    }
-    Property property;
-    if (!_properties.containsKey(propertySymbol)) {
-      if (_registeredProperties.containsKey(propertySymbol)) {
-        var constructor = _registeredProperties[propertySymbol].objectConstructor;
-        if (constructor == null)
-          return super.noSuchMethod(invocation);
-        property = constructor(propertySymbol, this);
-      } else {
-        return super.noSuchMethod(invocation);
-      }
-    } else {
-      property = _properties[propertySymbol];
-    }
-    if (invocation.isMethod) {
-      if (property is Function)
-        return Function.apply(property as Function, invocation.positionalArguments, invocation.namedArguments);
-      return super.noSuchMethod(invocation);
-    }
-    if (invocation.isSetter)
-      return Function.apply(property.setter, invocation.positionalArguments, invocation.namedArguments);
-    return property;
-  }
-}
-
-const initial = const Object();
-const inherit = const Object();
-
-abstract class Property {
-  Property(this.propertySymbol, this.declaration);
-  final StyleDeclaration declaration;
-  final Symbol propertySymbol;
-
-  bool get inherited => _registeredProperties[propertySymbol].inherited;
-
-  bool get initial => _isInitial();
-  void set initial (value) {
-    if (value == true)
-      return _setInitial();
-    throw new ArgumentError(value);
-  }
-
-  bool get inherit => _isInherit();
-  void set inherit (value) {
-    if (value == true)
-      return _setInherit();
-    throw new ArgumentError(value);
-  }
-
-  void setter(dynamic newValue) {
-    switch (newValue) {
-      case initial:
-        _setInitial();
-      case inherit:
-        _setInherit();
-      case null:
-        _unset();
-      default:
-        throw new ArgumentError(value);
-    }
-  }
-
-  external bool _isInitial();
-  external void _setInitial();
-  external bool _isInherit();
-  external void _setInherit();
-  external void _unset();
-}
-```
-
-Sky defines the following properties, currently as part of the core,
-but eventually this will be moved to the framework:
-
-```dart
-class LengthProperty extends Property {
-  LengthProperty(Symbol propertySymbol, StyleDeclaration declaration) : super(propertySymbol, declaration);
-
-  double get pixels => _getPixels();
-  void set pixels (value) => _setPixels(value);
-
-  double get inches => _getPixels() / 96.0;
-  void set inches (value) => _setPixels(value * 96.0);
-
-  double get em => _getEm();
-  void set em (value) => _setEm(value);
-
-  void setter(dynamic value) {
-    if (value is num)
-      return _setPixels(value.toDouble());
-    return super.setter(value);
-  }
-
-  external double _getPixels();
-  // throws StateError if the value isn't in pixels
-  external void _setPixels(double value);
-
-  external double _getEm();
-  // throws StateError if the value isn't in pixels
-  external void _setEm(double value);
-}
-
-const auto = const Object();
-
-class AutoLengthProperty extends LengthProperty {
-  AutoLengthProperty(Symbol propertySymbol, StyleDeclaration declaration) : super(propertySymbol, declaration);
-
-  bool get auto => _isAuto();
-  void set auto (value) {
-    if (value == true)
-      _setAuto();
-    throw new ArgumentError(value);
-  }
-
-  void setter(dynamic value) {
-    if (value == auto)
-      return _setAuto();
-    return super.setter(value);
-  }
-
-  external bool _isAuto();
-  external void _setAuto();
-}
-
-class ColorProperty extends Property {
-  ColorProperty(Symbol propertySymbol, StyleDeclaration declaration) : super(propertySymbol, declaration);
-
-  int get alpha => _getRGBA() & 0xFF000000 >> 24;
-  void set alpha (int value) => _setRGBA(_getRGBA() & 0x00FFFFFF + value << 24);
-  int get red => _getRGBA() & 0x00FF0000 >> 16;
-  void set red (int value) => _setRGBA(_getRGBA() & 0xFF00FFFF + value << 16);
-  int get green => _getRGBA() & 0x0000FF00 >> 8;
-  void set green (int value) => _setRGBA(_getRGBA() & 0xFFFF00FF + value << 8);
-  int get blue => _getRGBA() & 0x000000FF >> 0;
-  void set blue (int value) => _setRGBA(_getRGBA() & 0xFFFFFF00 + value << 0);
-
-  int get rgba => _getRGBA();
-  void set rgba (int value) => _setRGBA(value);
-
-  void setter(dynamic value) {
-    if (value is int)
-      return _setRGBA(value);
-    return super.setter(value);
-  }
-
-  external int _getRGBA();
-  // throws StateError if the value isn't a color
-  external void _setRGBA(int value);
-}
-
-class Matrix {
-  const Matrix(this.a, this.b, this.c, this.d, this.e, this.f);
-
-  // +-     -+
-  // | a c e |
-  // | b d f |
-  // | 0 0 1 |
-  // +-     -+
-  
-  final double a;
-  final double b;
-  final double c;
-  final double d;
-  final double e;
-  final double f;
-}
-
-class TransformProperty extends Property {
-  TransformProperty(Symbol propertySymbol, StyleDeclaration declaration) : super(propertySymbol, declaration);
-
-  void reset() => setTransform(1.0, 0.0, 0.0, 1.0, 0.0, 0.0);
-
-  void translate(double dx, double dy) => transform(1.0, 0.0, 0.0, 1.0, dx, dy);
-  void scale(double dw, double dh) => transform(dw, 0.0, 0.0, dh, 0.0, 0.0);
-  void rotate(double theta) => transform(cos(theta), -sin(theta), sin(theta), cos(theta), 0.0, 0.0);
-
-  // there's no "transform" getter since it would always return a new Matrix
-  // such that foo.transform == foo.transform would never be true
-  // and foo.transform = bar; bar == foo.transform would also never be true
-  // which is bad API
-
-  external Matrix getTransform();
-  // throws StateError if the value isn't a matrix
-  // returns a new matrix each time
-  external void setTransform(a, b, c, d, e, f);
-  external void transform(a, b, c, d, e, f);
-  // throws StateError if the value isn't a matrix
-}
-
-external void autoLengthPropertyStringSetter(Symbol propertySymbol, StyleDeclaration declaration, String value);
-external String autoLengthPropertyStringGetter(Symbol propertySymbol, StyleDeclaration declaration);
-external void colorPropertyStringSetter(Symbol propertySymbol, StyleDeclaration declaration, String value);
-external String colorPropertyStringGetter(Symbol propertySymbol, StyleDeclaration declaration);
-external void transformPropertyStringSetter(Symbol propertySymbol, StyleDeclaration declaration, String value);
-external String transformPropertyStringGetter(Symbol propertySymbol, StyleDeclaration declaration);
-
-void _init() {
-  registerProperty(new PropertyTable(   
-    symbol: #height,
-    inherited: false,
-    stringSetter: autoLengthPropertyStringSetter,
-    stringGetter: autoLengthPropertyStringGetter,
-    objectConstructor: (Symbol propertySymbol, StyleDeclaration declaration) =>
-                         new AutoLengthProperty(propertySymbol, declaration)));
-  registerProperty(new PropertyTable(   
-    symbol: #width,
-    inherited: false,
-    stringSetter: autoLengthPropertyStringSetter,
-    stringGetter: autoLengthPropertyStringGetter,
-    objectConstructor: (Symbol propertySymbol, StyleDeclaration declaration) =>
-                         new AutoLengthProperty(propertySymbol, declaration)));
-  registerProperty(new PropertyTable(   
-    symbol: #color,
-    inherited: false,
-    stringSetter: colorPropertyStringSetter,
-    stringGetter: colorPropertyStringGetter,
-    objectConstructor: (Symbol propertySymbol, StyleDeclaration declaration) =>
-                         new ColorProperty(propertySymbol, declaration)));
-  registerProperty(new PropertyTable(   
-    symbol: #transform,
-    inherited: false,
-    stringSetter: transformPropertyStringSetter,
-    stringGetter: transformPropertyStringGetter,
-    objectConstructor: (Symbol propertySymbol, StyleDeclaration declaration) =>
-                         new TransformProperty(propertySymbol, declaration)));
-}
-```
-
diff --git a/specs/utils.md b/specs/utils.md
deleted file mode 100644
index de8da83ba75..00000000000
--- a/specs/utils.md
+++ /dev/null
@@ -1,22 +0,0 @@
-Dart Utilities Used By dart:sky
-===============================
-
-The classes defined here are used internally by dart:sky but are
-pretty generic.
-
-```dart
-class Pair<A, B> {
-  const Pair(this.a, this.b);
-  final A a;
-  final B b;
-  int get hashCode => a.hashCode ^ b.hashCode;
-  bool operator==(other) => other is Pair<A, B> && a == other.a && b == other.b;
-}
-
-// MapOfWeakReferences can be implemented in C, using the C Dart API, apparently
-class MapOfWeakReferences<Key, Value> {
-  external operator[](Key key);
-  external operator[]=(Key key, Value value);
-  external bool containsKey(Key key);
-}
-```