diff --git a/.gitignore b/.gitignore
index c6f6fff..84e96ae 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 node_modules/
 coverage/
 demo/
+apidoc/
 *.log
diff --git a/.ndocrc b/.ndocrc
new file mode 100644
index 0000000..047f632
--- /dev/null
+++ b/.ndocrc
@@ -0,0 +1,25 @@
+#
+# Common nodeca config
+################################################################################
+
+--index         "./README.md"
+--package       "./package.json"
+--gh-ribbon     "{package.homepage}"
+--output        "apidoc"
+--render        "html"
+--link-format   "{package.homepage}/blob/master/{file}#L{line}"
+--broken-links  "show"
+
+
+#
+# Paths with sources
+################################################################################
+
+lib
+
+
+#
+# Project specific configuration
+################################################################################
+
+--show-all
diff --git a/.npmignore b/.npmignore
index f109ac6..7535526 100644
--- a/.npmignore
+++ b/.npmignore
@@ -2,6 +2,7 @@ benchmark/
 coverage/
 demo/
 docs/
+apidoc/
 support/
 test/
 Makefile
diff --git a/Makefile b/Makefile
index fd21fb1..fd42f98 100644
--- a/Makefile
+++ b/Makefile
@@ -44,7 +44,7 @@ lint:
 	eslint --reset .
 
 test: lint
-	NODE_ENV=test mocha -R spec
+	mocha -R spec
 	echo "CommonMark stat:\n"
 	./support/specsplit.js test/fixtures/commonmark/spec.txt
 
@@ -55,6 +55,15 @@ coverage:
 test-ci: lint
 	istanbul cover ./node_modules/mocha/bin/_mocha --report lcovonly -- -R spec && cat ./coverage/lcov.info | ./node_modules/coveralls/bin/coveralls.js && rm -rf ./coverage
 
+apidoc:
+	@if test ! `which ndoc` ; then \
+		echo "You need 'ndoc' installed in order to generate docs." >&2 ; \
+		echo "  $ npm install -g ndoc" >&2 ; \
+		exit 128 ; \
+		fi
+	rm -rf ./apidoc
+	ndoc --link-format "{package.homepage}/blob/${CURR_HEAD}/{file}#L{line}"
+
 publish:
 	@if test 0 -ne `git status --porcelain | wc -l` ; then \
 		echo "Unclean working tree. Commit or stash changes first." >&2 ; \
@@ -87,5 +96,5 @@ todo:
 	grep 'TODO' -n -r ./lib 2>/dev/null || test true
 
 
-.PHONY: publish lint test gh-pages todo demo coverage
+.PHONY: publish lint test gh-pages todo demo coverage apidoc
 .SILENT: help lint test todo
diff --git a/README.md b/README.md
index bdfd43e..8efcacf 100644
--- a/README.md
+++ b/README.md
@@ -62,7 +62,7 @@ var md = window.markdownit();
 console.log(md.render('# markdown-it rulezz!'));
 ```
 
-Single lines rendering, without paragraph wrap:
+Single line rendering, without paragraph wrap:
 
 ```js
 var md = require('markdown-it')();
@@ -88,7 +88,7 @@ active syntax rules and options for common use cases.
   all rules enabled, but still without html, typographer & autolinker.
 - [default](https://github.com/markdown-it/markdown-it/blob/master/lib/presets/default.js) -
   when no preset name given.
-- [zero](https://github.com/markdown-it/markdown-it/blob/master/lib/presets/zero.js) -
+- ["zero"](https://github.com/markdown-it/markdown-it/blob/master/lib/presets/zero.js) -
   all rules disabled (useful to quickly setup your config via `.enable()`).
 
 
diff --git a/bower.json b/bower.json
index 98b4822..6ce438b 100644
--- a/bower.json
+++ b/bower.json
@@ -17,6 +17,7 @@
     "coverage",
     "demo",
     "docs",
+    "apidoc",
     "lib",
     "node_modules",
     "support",
diff --git a/lib/index.js b/lib/index.js
index 6dc8355..640db2e 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -5,13 +5,10 @@
 
 var utils        = require('./common/utils');
 var helpers      = require('./helpers');
-var assign       = require('./common/utils').assign;
-var isString     = require('./common/utils').isString;
 var Renderer     = require('./renderer');
 var ParserCore   = require('./parser_core');
 var ParserBlock  = require('./parser_block');
 var ParserInline = require('./parser_inline');
-var Ruler        = require('./ruler');
 
 var config = {
   'default': require('./presets/default'),
@@ -34,30 +31,178 @@ function StateCore(self, src, env) {
   this.typographer = self.typographer;
 }
 
-// Main class
-//
+/**
+ * class MarkdownIt
+ *
+ * Main parser/renderer class.
+ *
+ * ##### Usage
+ *
+ * ```javascript
+ * // node.js, "classic" way:
+ * var MarkdownIt = require('markdown-it'),
+ *     md = new MarkdownIt();
+ * console.log(md.render('# markdown-it rulezz!'));
+ *
+ * // node.js, the same, but with sugar:
+ * var md = require('markdown-it')();
+ * console.log(md.render('# markdown-it rulezz!'));
+ *
+ * // browser without AMD, added to "window" on script load
+ * // Note, there are no dash.
+ * var md = window.markdownit();
+ * console.log(md.render('# markdown-it rulezz!'));
+ * ```
+ *
+ * Single line rendering, without paragraph wrap:
+ *
+ * ```javascript
+ * var md = require('markdown-it')();
+ * console.log(md.renderInline('__markdown-it__ rulezz!'));
+ * ```
+ **/
+
+/**
+ * new MarkdownIt([presetName, options])
+ * - presetName (String): optional, `commonmark` / `full` / `zero`
+ * - options (Object)
+ *
+ * Creates parser instanse with given config. Can be called without `new`.
+ *
+ * ##### presetName
+ *
+ * MarkdownIt provides named presets as a convenience to quickly
+ * enable/disable active syntax rules and options for common use cases.
+ *
+ * - ["commonmark"](https://github.com/markdown-it/markdown-it/blob/master/lib/presets/commonmark.js) -
+ *   configures parser to strict [CommonMark](http://commonmark.org/) mode.
+ * - ["full"](https://github.com/markdown-it/markdown-it/blob/master/lib/presets/full.js) -
+ *   enables all available rules, but still without html, typographer & autolinker.
+ * - [default](https://github.com/markdown-it/markdown-it/blob/master/lib/presets/default.js) -
+ *   similar to GFM, used when no preset name given.
+ * - ["zero"](https://github.com/markdown-it/markdown-it/blob/master/lib/presets/zero.js) -
+ *   all rules disabled. Useful to quickly setup your config via `.enable()`.
+ *   For example, when you need only `bold` and `italic` markup and nothing else.
+ *
+ * ##### options:
+ *
+ * - __html__ - `false`. Set `true` to enable HTML tags in source. Be careful!
+ *   That's not safe! You may need external sanitizer to protect output from XSS.
+ *   It's better to extend features via plugins, instead of enabling HTML.
+ * - __xhtmlOut__ - `false`. Set `true` to add '/' when closing single tags
+ *   (`<br />`). This is needed only for full CommonMark compatibility. In real
+ *   world you will need HTML output.
+ * - __breaks__ - `false`. Set `true` to convert `\n` in paragraphs into `<br>`.
+ * - __langPrefix__ - `language-`. CSS language class prefix for fenced blocks.
+ *   Can be useful for external highlighters.
+ * - __linkify__ - `false`. Set `true` to autoconvert URL-like text to links.
+ * - __typographer__  - `false`. Set `true` to enable some language-neutral
+ *   replacement + quotes beautification (smartquotes).
+ * - __quotes__ - `“”‘’`, string. Double + single quotes replacement pairs, when
+ *   typographer enabled and smartquotes on. Set doubles to '«»' for Russian,
+ *   '„“' for German.
+ * - __highlight__ - `null`. Highlighter function for fenced code blocks.
+ *   Highlighter `function (str, lang)` should return escaped HTML. It can also
+ *   return empty string if the source was not changed and should be escaped externaly.
+ *
+ * ##### Example
+ *
+ * ```javascript
+ * // commonmark mode
+ * var md = require('markdown-it')('commonmark');
+ *
+ * // default mode
+ * var md = require('markdown-it')();
+ *
+ * // enable everything
+ * var md = require('markdown-it')('full', {
+ *   html: true,
+ *   linkify: true,
+ *   typographer: true
+ * });
+ * ```
+ **/
 function MarkdownIt(presetName, options) {
   if (!(this instanceof MarkdownIt)) {
     return new MarkdownIt(presetName, options);
   }
 
   if (!options) {
-    if (!isString(presetName)) {
+    if (!utils.isString(presetName)) {
       options = presetName || {};
       presetName = 'default';
     }
   }
 
-  this.inline   = new ParserInline();
-  this.block    = new ParserBlock();
-  this.core     = new ParserCore();
+  /**
+   * MarkdownIt#inline -> ParserInline
+   *
+   * Instance of inline parser. You may need it to add new rules when
+   * writing plugins. For simple rules control use [[MarkdownIt.disable]] and
+   * [[MarkdownIt.enable]].
+   **/
+  this.inline = new ParserInline();
+
+  /**
+   * MarkdownIt#block -> ParserBlock
+   *
+   * Instance of block parser. You may need it to add new rules when
+   * writing plugins. For simple rules control use [[MarkdownIt.disable]] and
+   * [[MarkdownIt.enable]].
+   **/
+  this.block = new ParserBlock();
+
+  /**
+   * MarkdownIt#core -> ParserCore
+   *
+   * Instance of core chain executor. You may need it to add new rules when
+   * writing plugins. For simple rules control use [[MarkdownIt.disable]] and
+   * [[MarkdownIt.enable]].
+   **/
+  this.core = new ParserCore();
+
+  /**
+   * MarkdownIt#renderer -> Renderer
+   *
+   * Instance of Renderer. Use it to modify output look. Or to add rendering
+   * rules for new token types, generated by plugins.
+   *
+   * ##### Example
+   *
+   * ```javascript
+   * var md = require('markdown-it')();
+   *
+   * function myToken(tokens, idx, options, env, self) {
+   *   //...
+   *   return result;
+   * };
+   *
+   * md.renderer.rules['my_token'] = myToken
+   * ```
+   *
+   * See [[Renderer]] docs and [source code](https://github.com/markdown-it/markdown-it/blob/master/lib/renderer.js).
+   **/
   this.renderer = new Renderer();
-  this.ruler    = new Ruler();
 
   // Expose utils & helpers for easy acces from plugins
+
+  /**
+   * MarkdownIt#utils -> utils
+   *
+   * Assorted utility functions, useful to write plugins. See details
+   * [here](https://github.com/markdown-it/markdown-it/blob/master/lib/common/utils.js).
+   **/
   this.utils    = utils;
+
+  /**
+   * MarkdownIt#helpers -> helpers
+   *
+   * Link components parser functions, useful to write plugins. See details
+   * [here](https://github.com/markdown-it/markdown-it/blob/master/lib/helpers).
+   **/
   this.helpers  = helpers;
 
+
   this.options  = {};
   this.configure(config[presetName]);
 
@@ -65,16 +210,38 @@ function MarkdownIt(presetName, options) {
 }
 
 
-// Set options, if you did not passed those to constructor
-//
+/** chainable
+ * MarkdownIt.set(options)
+ *
+ * Set parser options (in the same format as in constructor). Probably, you
+ * will never need it, but you can change options after constructor call.
+ *
+ * ##### Example
+ *
+ * ```javascript
+ * var md = require('markdown-it')()
+ *             .set({ html: true, breaks: true })
+ *             .set({ typographer, true });
+ * ```
+ *
+ * __Note:__ To achieve the best possible performance, don't modify a
+ * `markdown-it` instance options on the fly. If you need multiple configurations
+ * it's best to create multiple instances and initialize each with separate
+ * config.
+ **/
 MarkdownIt.prototype.set = function (options) {
-  assign(this.options, options);
+  utils.assign(this.options, options);
   return this;
 };
 
 
-// Batch loader for components rules states & options
-//
+/** chainable, internal
+ * MarkdownIt.configure(presets)
+ *
+ * Batch load of all options and compenent settings. This is internal method,
+ * and you probably will not need it. But if you with - see available presets
+ * and data structure [here](https://github.com/markdown-it/markdown-it/tree/master/lib/presets)
+ **/
 MarkdownIt.prototype.configure = function (presets) {
   var self = this;
 
@@ -93,8 +260,21 @@ MarkdownIt.prototype.configure = function (presets) {
 };
 
 
-// Sugar to enable rules by names in all chains at once
-//
+/** chainable
+ * MarkdownIt.enable(list)
+ * - list (String|Array): rule name or list of rule names to enable
+ *
+ * Enable list or rules. It will automatically find appropriate components,
+ * containing rules with given names.
+ *
+ * ##### Example
+ *
+ * ```javascript
+ * var md = require('markdown-it')()
+ *             .enable(['sub', 'sup'])
+ *             .disable('smartquotes');
+ * ```
+ **/
 MarkdownIt.prototype.enable = function (list) {
   [ 'core', 'block', 'inline' ].forEach(function (chain) {
     this[chain].ruler.enable(list, true);
@@ -103,8 +283,12 @@ MarkdownIt.prototype.enable = function (list) {
 };
 
 
-// Sugar to disable rules by names in all chains at once
-//
+/** chainable
+ * MarkdownIt.disable(list)
+ * - list (String|Array): rule name or list of rule names to disable.
+ *
+ * The same as [[MarkdownIt.enable]], but turn specified rules off.
+ **/
 MarkdownIt.prototype.disable = function (list) {
   [ 'core', 'block', 'inline' ].forEach(function (chain) {
     this[chain].ruler.disable(list, true);
@@ -113,23 +297,37 @@ MarkdownIt.prototype.disable = function (list) {
 };
 
 
-// Sugar for curried plugins init:
-//
-// var md = new MarkdownIt();
-//
-// md.use(plugin1)
-//   .use(plugin2, opts)
-//   .use(plugin3);
-//
-MarkdownIt.prototype.use = function (plugin, opts) {
-  plugin(this, opts);
+/** chainable
+ * MarkdownIt.use(plugin, options)
+ *
+ * Load specified plugin with given options into current parser instance.
+ *
+ * ##### Example
+ *
+ * ```javascript
+ * var md = require('markdown-it')()
+ *             .use(require('makkdown-it-emoji'));
+ * ```
+ **/
+MarkdownIt.prototype.use = function (plugin, options) {
+  plugin(this, options);
   return this;
 };
 
 
-// Parse input string, returns tokens array. Modify `env` with
-// definitions data.
-//
+/** internal
+ * MarkdownIt.parse(src, env) -> Array
+ * - src (String): source string
+ * - env (Object): enviroment variables
+ *
+ * Parse input string and returns list of block tokens (special token type
+ * "inline" will contain list of inline tokens). You should not call this
+ * method directly, until you write custom renderer (for example, to produce
+ * AST).
+ *
+ * `env` is modified with additional info. For example, with references data.
+ * Also `env` can be used to pass external info to plugins.
+ **/
 MarkdownIt.prototype.parse = function (src, env) {
   var state = new StateCore(this, src, env);
 
@@ -139,8 +337,16 @@ MarkdownIt.prototype.parse = function (src, env) {
 };
 
 
-// Main method that does all magic :)
-//
+/**
+ * MarkdownIt.render(src [, env]) -> String
+ * - src (String): source string
+ * - env (Object): optional, enviroment variables
+ *
+ * Render markdown string into html. It does all magic for you :).
+ *
+ * `env` is `{}` by default. It's not used now directly, but you can pass
+ *  with it any additional data to plugins.
+ **/
 MarkdownIt.prototype.render = function (src, env) {
   env = env || {};
 
@@ -148,8 +354,13 @@ MarkdownIt.prototype.render = function (src, env) {
 };
 
 
-// Parse content as single string
-//
+/** internal
+ * MarkdownIt.parseInline(src, env) -> Array
+ * - src (String): source string
+ * - env (Object): enviroment variables
+ *
+ * The same as [[MarkdownIt.parse]] but skip all block rules.
+ **/
 MarkdownIt.prototype.parseInline = function (src, env) {
   var state = new StateCore(this, src, env);
 
@@ -160,8 +371,14 @@ MarkdownIt.prototype.parseInline = function (src, env) {
 };
 
 
-// Render single string, without wrapping it to paragraphs
-//
+/**
+ * MarkdownIt.renderInline(src [, env]) -> String
+ * - src (String): source string
+ * - env (Object): optional, enviroment variables
+ *
+ * Similar to [[MarkdownIt.render]] but for single paragraph content. Result
+ * will NOT be wrapped into `<p>` tags.
+ **/
 MarkdownIt.prototype.renderInline = function (src, env) {
   env = env || {};