diff --git a/lib/common/utils.js b/lib/common/utils.js
index b5e59b4..0f31d58 100644
--- a/lib/common/utils.js
+++ b/lib/common/utils.js
@@ -124,6 +124,11 @@ function escapeHtml(str) {
 
 ////////////////////////////////////////////////////////////////////////////////
 
+function arrayReplaceAt(src, pos, newElements) {
+  return [].concat(src.slice(0, pos), newElements, src.slice(pos + 1));
+}
+
+
 exports.assign            = assign;
 exports.isString          = isString;
 exports.has               = has;
@@ -132,3 +137,4 @@ exports.isValidEntityCode = isValidEntityCode;
 exports.fromCodePoint     = fromCodePoint;
 exports.replaceEntities   = replaceEntities;
 exports.escapeHtml        = escapeHtml;
+exports.arrayReplaceAt    = arrayReplaceAt;
diff --git a/lib/index.js b/lib/index.js
index 65a291a..8d7bc68 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -3,6 +3,7 @@
 'use strict';
 
 
+var utils        = require('./common/utils');
 var assign       = require('./common/utils').assign;
 var isString     = require('./common/utils').isString;
 var Renderer     = require('./renderer');
@@ -51,6 +52,9 @@ function MarkdownIt(presetName, options) {
   this.renderer = new Renderer();
   this.ruler    = new Ruler();
 
+  // Expose utils for easy acces from plugins
+  this.utils    = utils;
+
   this.options  = {};
   this.configure(config[presetName]);
 
diff --git a/lib/rules_core/abbr2.js b/lib/rules_core/abbr2.js
index cdc03ce..0a3315c 100644
--- a/lib/rules_core/abbr2.js
+++ b/lib/rules_core/abbr2.js
@@ -3,6 +3,9 @@
 'use strict';
 
 
+var arrayReplaceAt = require('../common/utils').arrayReplaceAt;
+
+
 var PUNCT_CHARS = ' \n()[]\'".,!?-';
 
 
@@ -82,7 +85,7 @@ module.exports = function abbr2(state) {
       }
 
       // replace current node
-      blockTokens[j].children = tokens = [].concat(tokens.slice(0, i), nodes, tokens.slice(i + 1));
+      blockTokens[j].children = tokens = arrayReplaceAt(tokens, i, nodes);
     }
   }
 };
diff --git a/lib/rules_core/linkify.js b/lib/rules_core/linkify.js
index 4bd8625..b8a958c 100644
--- a/lib/rules_core/linkify.js
+++ b/lib/rules_core/linkify.js
@@ -5,7 +5,8 @@
 'use strict';
 
 
-var Autolinker = require('autolinker');
+var Autolinker     = require('autolinker');
+var arrayReplaceAt = require('../common/utils').arrayReplaceAt;
 
 
 var LINK_SCAN_RE = /www|@|\:\/\//;
@@ -154,7 +155,7 @@ module.exports = function linkify(state) {
         }
 
         // replace current node
-        blockTokens[j].children = tokens = [].concat(tokens.slice(0, i), nodes, tokens.slice(i + 1));
+        blockTokens[j].children = tokens = arrayReplaceAt(tokens, i, nodes);
       }
     }
   }