diff --git a/source/Ox.Image/Ox.Image.js b/source/Ox.Image/Ox.Image.js
index 2c95526c..c4f6eb64 100644
--- a/source/Ox.Image/Ox.Image.js
+++ b/source/Ox.Image/Ox.Image.js
@@ -355,7 +355,7 @@ Ox.load.Image = function(options, callback) {
             while (str.length < cap) {
                 str += str.substr(4, len);
             }
-            str = str.substr(0, Math.ceil(cap));
+            str = str.slice(0, Math.ceil(cap));
             // Create an array of bit values
             bin = Ox.flatten(Ox.map(str.split(''), function(chr) {
                 return Ox.range(8).map(function(i) {
diff --git a/source/Ox.UI/js/Code/Ox.SourceViewer.js b/source/Ox.UI/js/Code/Ox.SourceViewer.js
index 36dae3f0..a3a2f836 100644
--- a/source/Ox.UI/js/Code/Ox.SourceViewer.js
+++ b/source/Ox.UI/js/Code/Ox.SourceViewer.js
@@ -30,7 +30,7 @@ Ox.SourceViewer = function(options, self) {
                         return match ? match[0].length : 0;
                     }));
                 return '<pre>' + lines.map(function(line) {
-                    return line.substr(indent);
+                    return line.slice(indent);
                 }).join('\n') + '</pre>';
             }
         ]
diff --git a/source/Ox.UI/js/Core/Ox.URL.js b/source/Ox.UI/js/Core/Ox.URL.js
index 59edf95b..fadc202d 100644
--- a/source/Ox.UI/js/Core/Ox.URL.js
+++ b/source/Ox.UI/js/Core/Ox.URL.js
@@ -336,10 +336,10 @@ Ox.URL = function(options) {
         }
         if (['=', '!='].indexOf(condition.operator) > -1) {
             if (condition.value[0] == '*') {
-                condition.value = condition.value.substr(1);
+                condition.value = condition.value.slice(1);
                 condition.operator = condition.operator.replace('=', '$')
             } else if (condition.value[condition.value.length - 1] == '*') {
-                condition.value = condition.value.substr(0, condition.value.length - 1);
+                condition.value = condition.value.slice(0, -1);
                 condition.operator = condition.operator.replace('=', '^')
             }
         }
@@ -417,7 +417,7 @@ Ox.URL = function(options) {
         return str.split(',').map(function(str) {
             var hasOperator = /^[\+-]/.test(str);
             return {
-                key: hasOperator ? str.substr(1) : str,
+                key: hasOperator ? str.slice(1) : str,
                 operator: hasOperator
                     ? str[0]
                     : Ox.getObjectById(self.options.sortKeys[state.type][
diff --git a/source/Ox.UI/js/Form/Ox.Button.js b/source/Ox.UI/js/Form/Ox.Button.js
index c8cad30b..09d96264 100644
--- a/source/Ox.UI/js/Form/Ox.Button.js
+++ b/source/Ox.UI/js/Form/Ox.Button.js
@@ -113,7 +113,7 @@ Ox.Button = function(options, self) {
             that.attr({
                 src: Ox.UI.getImageURL(
                     'symbol' + self.options.title[0].toUpperCase()
-                    + self.options.title.substr(1)
+                    + self.options.title.slice(1)
                 )
             });
         } else {
diff --git a/source/Ox.UI/js/Form/Ox.Input.js b/source/Ox.UI/js/Form/Ox.Input.js
index b761d370..ae6f7849 100644
--- a/source/Ox.UI/js/Form/Ox.Input.js
+++ b/source/Ox.UI/js/Form/Ox.Input.js
@@ -513,7 +513,7 @@ Ox.Input = function(options, self) {
                 } else if (/\./.test(value) && self.options.decimals) {
                     length = value.split('.')[1].length;
                     if (length > self.options.decimals) {
-                        value = value.substr(0, value.indexOf('.') + 1 + self.options.decimals);
+                        value = value.slice(0, value.indexOf('.') + 1 + self.options.decimals);
                         cursor = [oldCursor[0] + 1, oldCursor[1] + 1];
                     } else if (length < self.options.decimals) {
                         value += Ox.repeat('0', self.options.decimals - length);
@@ -527,7 +527,7 @@ Ox.Input = function(options, self) {
                 }
             }
             while (/^0\d/.test(value)) {
-                value = value.substr(1, value.length);
+                value = value.slice(1);
             }
             if (!regexp.test(value) || value < self.options.min || value > self.options.max) {
                 value = oldValue;
@@ -725,7 +725,7 @@ Ox.Input = function(options, self) {
         that.triggerEvent('insert', {
             end: input.selectionEnd,
             id: that.oxid,
-            selection: input.value.substring(input.selectionStart, input.selectionEnd),
+            selection: input.value.slice(input.selectionStart, input.selectionEnd),
             start: input.selectionStart,
             value: input.value
         });
@@ -734,7 +734,7 @@ Ox.Input = function(options, self) {
     function keydown(event) {
         var oldCursor = cursor(),
             oldValue = self.options.value,
-            newValue = oldValue.substr(0, oldCursor[0] - 1),
+            newValue = oldValue.slice(0, oldCursor[0] - 1),
             hasDeletedSelectedEnd = (event.keyCode == 8 || event.keyCode == 46) &&
                 oldCursor[0] < oldCursor[1] && oldCursor[1] == oldValue.length;
         if (
diff --git a/source/Ox.UI/js/Form/Ox.InsertHTMLDialog.js b/source/Ox.UI/js/Form/Ox.InsertHTMLDialog.js
index 248258a3..6d13b52d 100644
--- a/source/Ox.UI/js/Form/Ox.InsertHTMLDialog.js
+++ b/source/Ox.UI/js/Form/Ox.InsertHTMLDialog.js
@@ -190,9 +190,9 @@ Ox.InsertHTMLDialog = function(options, self) {
                             );
                         self.options.callback({
                             position: self.options.start + value.length,
-                            value: self.options.value.substr(0, self.options.start)
+                            value: self.options.value.slice(0, self.options.start)
                                 + value
-                                + self.options.value.substr(self.options.end)
+                                + self.options.value.slice(self.options.end)
                         });
                         that.close();
                     }
diff --git a/source/Ox.UI/js/Form/Ox.TimeInput.js b/source/Ox.UI/js/Form/Ox.TimeInput.js
index 6e6b0e02..3392b569 100644
--- a/source/Ox.UI/js/Form/Ox.TimeInput.js
+++ b/source/Ox.UI/js/Form/Ox.TimeInput.js
@@ -119,7 +119,7 @@ Ox.TimeInput = function(options, self) {
     function getDate() {
         return new Date('1970/01/01 ' + (
             self.options.milliseconds
-                ? self.options.value.substr(0, self.options.value.length - 4)
+                ? self.options.value.slice(0, -4)
                 : self.options.value
         ));
     }
@@ -129,7 +129,7 @@ Ox.TimeInput = function(options, self) {
         return {
             ampm: Ox.formatDate(date, '%p'),
             hours: Ox.formatDate(date, self.options.ampm ? '%I' : '%H'),
-            milliseconds: self.options.milliseconds ? self.options.value.substr(-3) : '000',
+            milliseconds: self.options.milliseconds ? self.options.value.slice(-3) : '000',
             minutes: Ox.formatDate(date, '%M'),
             seconds: Ox.formatDate(date, '%S')
         };
diff --git a/source/Ox.UI/js/Map/Ox.ListMap.js b/source/Ox.UI/js/Map/Ox.ListMap.js
index 451dd10c..0c775163 100644
--- a/source/Ox.UI/js/Map/Ox.ListMap.js
+++ b/source/Ox.UI/js/Map/Ox.ListMap.js
@@ -774,7 +774,7 @@ Ox.ListMap = function(options, self) {
             country = Ox.getCountryByGeoname(place.geoname);
         place.countryCode = country ? country.code : '';
         if (!self.isAsync) {
-            place.id = self.selectedPlace.substr(1); // fixme: safe?
+            place.id = self.selectedPlace.slice(1); // fixme: safe?
             self.selectedPlace = place.id;
             self.options.places.push(place);
             self.$list.options({
diff --git a/source/Ox.UI/js/Video/Ox.AnnotationPanel.js b/source/Ox.UI/js/Video/Ox.AnnotationPanel.js
index 4bba3994..1bbf5f42 100644
--- a/source/Ox.UI/js/Video/Ox.AnnotationPanel.js
+++ b/source/Ox.UI/js/Video/Ox.AnnotationPanel.js
@@ -302,8 +302,9 @@ Ox.AnnotationPanel = function(options, self) {
                     insert({
                         end: element.selectionEnd,
                         id: id,
-                        selection: element.value
-                            .substr(element.selectionStart, element.selectionEnd),
+                        selection: element.value.slice(
+                            element.selectionStart, element.selectionEnd
+                        ),
                         start: element.selectionStart,
                         value: element.value
                     });
diff --git a/source/Ox.UI/js/Video/Ox.VideoElement.js b/source/Ox.UI/js/Video/Ox.VideoElement.js
index b1129857..29d250b5 100644
--- a/source/Ox.UI/js/Video/Ox.VideoElement.js
+++ b/source/Ox.UI/js/Video/Ox.VideoElement.js
@@ -89,7 +89,7 @@ Ox.VideoElement = function(options, self) {
         item.$videos = src.map(function(src, i) {
             // in all browsers except firefox,
             // loadedmetadata fires only once per src
-            if(Ox.parseURL(src).protocol.substr(0, 4) == 'http') {
+            if (Ox.startsWith(Ox.parseURL(src).protocol, 'http')) {
                 src += '?' + Ox.uid();
             }
             return $('<video>')
@@ -434,7 +434,7 @@ Ox.VideoElement = function(options, self) {
                 self.$video.each(function(video, i) {
                     if (i != self.currentPart) {
                         var src = self.options.src[i];
-                        if(Ox.parseURL(src).protocol.substr(0, 4) == 'http') {
+                        if (Ox.startsWith(Ox.parseURL(src).protocol, 'http')) {
                             src += '?' + Ox.uid();
                         }
                         video.src = src;
@@ -443,7 +443,7 @@ Ox.VideoElement = function(options, self) {
             } else {
                 self.items[0].$videos.forEach(function($video, i) {
                     var src = self.options.src[i];
-                    if (Ox.parseURL(src).protocol.substr(0, 4) == 'http') {
+                    if (Ox.startsWith(Ox.parseURL(src).protocol, 'http')) {
                         src += '?' + Ox.uid();
                     }
                     $video[0].src = src;
diff --git a/source/Ox.UI/js/Window/Ox.Dialog.js b/source/Ox.UI/js/Window/Ox.Dialog.js
index fb7e68a8..3b7d63a8 100644
--- a/source/Ox.UI/js/Window/Ox.Dialog.js
+++ b/source/Ox.UI/js/Window/Ox.Dialog.js
@@ -309,7 +309,7 @@ Ox.Dialog = function(options, self) {
     }
 
     function resizestart(event) {
-        var edge = event.target.className.substr(17).toLowerCase(),
+        var edge = event.target.className.slice(17).toLowerCase(),
             offset = that.offset();
         self.drag = {
             edge: edge,
diff --git a/source/Ox/js/Array.js b/source/Ox/js/Array.js
index 3944672f..a9ae327b 100644
--- a/source/Ox/js/Array.js
+++ b/source/Ox/js/Array.js
@@ -462,8 +462,8 @@ Ox.range = function() {
                     var len;
                     if (new RegExp('^' + article + ' ').test(sort[val])) {
                         len = article.length;
-                        sort[val] = sort[val].substr(len + 1) + ', '
-                            + sort[val].substr(0, len);
+                        sort[val] = sort[val].slice(len + 1) + ', '
+                            + sort[val].slice(0, len);
                         Ox.break();
                     }
                 });
diff --git a/source/Ox/js/Color.js b/source/Ox/js/Color.js
index 1c26e37b..3a2471de 100644
--- a/source/Ox/js/Color.js
+++ b/source/Ox/js/Color.js
@@ -119,4 +119,3 @@ Ox.toRGB = function(hex) {
         return parseInt(hex.substr(i * 2, 2), 16);
     });
 };
-
diff --git a/source/Ox/js/Constants.js b/source/Ox/js/Constants.js
index ac23c33a..9ba79d19 100644
--- a/source/Ox/js/Constants.js
+++ b/source/Ox/js/Constants.js
@@ -74,7 +74,7 @@ Ox.MONTHS = [
 ];
 //@ Ox.SHORT_MONTHS <[str]> Short names of months
 Ox.SHORT_MONTHS = Ox.MONTHS.map(function(val) {
-    return val.substr(0, 3);
+    return val.slice(0, 3);
 });
 //@ Ox.PATH <str> Path of Ox.js
 Ox.PATH = Ox.toArray(
@@ -127,5 +127,5 @@ Ox.WEEKDAYS = [
 ];
 //@ Ox.SHORT_WEEKDAYS <[str]> Short names of weekdays
 Ox.SHORT_WEEKDAYS = Ox.WEEKDAYS.map(function(val) {
-    return val.substr(0, 3);
-});
\ No newline at end of file
+    return val.slice(0, 3);
+});
diff --git a/source/Ox/js/Core.js b/source/Ox/js/Core.js
index b176678f..ca001303 100644
--- a/source/Ox/js/Core.js
+++ b/source/Ox/js/Core.js
@@ -141,7 +141,7 @@ Ox.localStorage = function(namespace) {
             ret = {};
             Ox.forEach(localStorage, function(val, key) {
                 if (Ox.startsWith(key, namespace + '.')) {
-                    ret[key.substr(namespace.length + 1)] = JSON.parse(val);
+                    ret[key.slice(namespace.length + 1)] = JSON.parse(val);
                 }
             });
         } else if (arguments.length == 1 && typeof key == 'string') {
@@ -214,7 +214,7 @@ Ox.Log = (function() {
         if (!log.filterEnabled || log.filter.indexOf(args[0]) > -1) {
             date = new Date();
             args.unshift(
-                Ox.formatDate(date, '%H:%M:%S.') + (+date).toString().substr(-3)
+                Ox.formatDate(date, '%H:%M:%S.') + (+date).toString().slice(-3)
             );
             window.console && window.console.log.apply(window.console, args);
             ret = args.join(' ');
@@ -326,7 +326,7 @@ Ox.print = function() {
     var args = Ox.toArray(arguments),
         date = new Date();
     args.unshift(
-        Ox.formatDate(date, '%H:%M:%S.') + (+date).toString().substr(-3)/*,
+        Ox.formatDate(date, '%H:%M:%S.') + (+date).toString().slice(-3)/*,
         (arguments.callee.caller && arguments.callee.caller.name)
         || '(anonymous)'*/
     );
diff --git a/source/Ox/js/Date.js b/source/Ox/js/Date.js
index 0aa4a759..3aaccafc 100644
--- a/source/Ox/js/Date.js
+++ b/source/Ox/js/Date.js
@@ -26,7 +26,7 @@ Ox.getDateInWeek = function(date, weekday, utc) {
     var sourceWeekday = Ox.getISODay(date, utc),
         targetWeekday = Ox.isNumber(weekday) ? weekday
             : Ox.indexOf(Ox.WEEKDAYS, function(v) {
-                return v.substr(0, 3) == weekday.substr(0, 3);
+                return v.slice(0, 3) == weekday.slice(0, 3);
             }) + 1;
     return Ox.setDate(date, Ox.getDate(date, utc) - sourceWeekday + targetWeekday, utc);
 }
@@ -72,7 +72,7 @@ Ox.getDaysInMonth = function(year, month) {
     year = Ox.makeYear(year);
     month = Ox.isNumber(month) ? month
         : Ox.indexOf(Ox.MONTHS, function(v) {
-            return v.substr(0, 3) == month.substr(0, 3);
+            return v.slice(0, 3) == month.slice(0, 3);
         }) + 1;
     return new Date(year, month, 0).getDate();
 }
diff --git a/source/Ox/js/Encoding.js b/source/Ox/js/Encoding.js
index d3b9bfcb..8e4e44d5 100644
--- a/source/Ox/js/Encoding.js
+++ b/source/Ox/js/Encoding.js
@@ -204,14 +204,14 @@
         // bytes IHDR name), keep bytes 16 to 19 (width), discard bytes 20 to 29
         // (4 bytes height, 5 bytes flags), keep bytes 29 to 32 (IHDR checksum),
         // keep the rest (IDAT chunks), discard the last 12 bytes (IEND chunk).
-        data = str.substr(16, 4) + str.substr(29, 4);
-        idat = str.substr(33, str.length - 45);
+        data = str.slice(16, 20) + str.slice(29, 33);
+        idat = str.slice(33, -45);
         while (idat) {
             // Each IDAT chunk is 4 bytes length, 4 bytes name, length bytes
             // data and 4 bytes checksum. We can discard the name parts.
-            len = idat.substr(0, 4);
-            data += len + idat.substr(8, 4 + (len = Ox.decodeBase256(len)));
-            idat = idat.substr(12 + len);
+            len = idat.slice(0, 4);
+            data += len + idat.slice(8, 12 + (len = Ox.decodeBase256(len)));
+            idat = idat.slice(12 + len);
         }
         callback && callback(data);
         return data;
@@ -234,18 +234,18 @@
         var image = new Image(),
             // PNG file signature and IHDR chunk
             data = '\u0089PNG\r\n\u001A\n\u0000\u0000\u0000\u000DIHDR'
-                + str.substr(0, 4) + '\u0000\u0000\u0000\u0001'
-                + '\u0008\u0006\u0000\u0000\u0000' + str.substr(4, 4),
+                + str.slice(0, 4) + '\u0000\u0000\u0000\u0001'
+                + '\u0008\u0006\u0000\u0000\u0000' + str.slice(4, 8),
             // IDAT chunks
-            idat = str.substr(8), len;
+            idat = str.slice(8), len;
         function error() {
             throw new RangeError('Deflate codec can\'t decode data.');
         }
         while (idat) {
             // Reinsert the IDAT chunk names
-            len = idat.substr(0, 4);
-            data += len + 'IDAT' + idat.substr(4, 4 + (len = Ox.decodeBase256(len)));
-            idat = idat.substr(8 + len);
+            len = idat.slice(0, 4);
+            data += len + 'IDAT' + idat.slice(4, 8 + (len = Ox.decodeBase256(len)));
+            idat = idat.slice(8 + len);
         }
         // IEND chunk
         data += '\u0000\u0000\u0000\u0000IEND\u00AE\u0042\u0060\u0082';
@@ -259,7 +259,7 @@
             try {
                 // Parse the first byte as number of bytes to chop at the end,
                 // and the rest, without these bytes, as an UTF8-encoded string.
-                str = Ox.decodeUTF8(str.substr(1, str.length - 1 - str.charCodeAt(0)))
+                str = Ox.decodeUTF8(str.slice(1, -str.CharCodeAt(0)));
             } catch (e) {
                 error();
             }
diff --git a/source/Ox/js/Format.js b/source/Ox/js/Format.js
index d56f0a56..88744b9f 100644
--- a/source/Ox/js/Format.js
+++ b/source/Ox/js/Format.js
@@ -153,7 +153,7 @@ Ox.formatDate = function(date, str, utc) {
         ['d', function(d) {return Ox.pad(Ox.getDate(d, utc), 2);}],
         ['e', function(d) {return Ox.pad(Ox.getDate(d, utc), 2, ' ');}],
         ['G', function(d) {return Ox.getISOYear(d, utc);}],
-        ['g', function(d) {return Ox.getISOYear(d, utc).toString().substr(-2);}],
+        ['g', function(d) {return Ox.getISOYear(d, utc).toString().slice(-2);}],
         ['H', function(d) {return Ox.pad(Ox.getHours(d, utc), 2);}],
         ['I', function(d) {return Ox.pad((Ox.getHours(d, utc) + 11) % 12 + 1, 2);}],
         ['j', function(d) {return Ox.pad(Ox.getDayOfTheYear(d, utc), 3);}],
@@ -185,7 +185,7 @@ Ox.formatDate = function(date, str, utc) {
             return Math.abs(y) + (y < 1000 ? ' ' + Ox.BCAD[y < 0 ? 0 : 1] : '');
         }],
         ['Y', function(d) {return Ox.getFullYear(d, utc);}],
-        ['y', function(d) {return Ox.getFullYear(d, utc).toString().substr(-2);}],
+        ['y', function(d) {return Ox.getFullYear(d, utc).toString().slice(-2);}],
         ['Z', function(d) {return d.toString().split('(')[1].replace(')', '');}],
         ['z', function(d) {return Ox.getTimezoneOffsetString(d);}],
         ['n', function() {return '\n';}],
@@ -496,8 +496,8 @@ Ox.formatNumber = function(num, dec) {
         str = Ox.isUndefined(dec) ? abs.toString() : abs.toFixed(dec),
         spl = str.split('.');
     while (spl[0]) {
-        arr.unshift(spl[0].substr(-3));
-        spl[0] = spl[0].substr(0, spl[0].length - 3);
+        arr.unshift(spl[0].slice(-3));
+        spl[0] = spl[0].slice(0, -3);
     }
     spl[0] = arr.join(',');
     return (num < 0 ? '-' : '') + spl.join('.');
diff --git a/source/Ox/js/JavaScript.js b/source/Ox/js/JavaScript.js
index fcebca11..2622bd1e 100644
--- a/source/Ox/js/JavaScript.js
+++ b/source/Ox/js/JavaScript.js
@@ -76,7 +76,7 @@ Ox.doc = (function() {
         // or if the second last char is a single or double quote
         return matches && (
             matches[2].indexOf('/') == -1 ||
-            '\'"'.indexOf(matches[2].substr(-2, 1)) > -1
+            '\'"'.indexOf(matches[2].slice(-2, -1)) > -1
         ) ? Ox.extend({
             name: parseName(matches[1].trim()),
             summary: matches[3].trim()
@@ -163,7 +163,7 @@ Ox.doc = (function() {
                     // main item
                     // include leading whitespace
                     item.source = parseTokens(tokens[i]);
-                    item.line = source.substr(0, item.source[0].offset)
+                    item.line = source.slice(0, item.source[0].offset)
                         .split('\n').length;
                     items.push(item);
                 } else {
@@ -186,7 +186,7 @@ Ox.doc = (function() {
         // fixme: we cannot properly handle tests where a string contains '\n '
         var lines = decodeLinebreaks(str).split('\n ');
         return {
-            statement: lines[0].substr(2),
+            statement: lines[0].slice(2),
             result: lines[1].trim()
         };
     }
@@ -258,7 +258,7 @@ Ox.doc = (function() {
             split,
             type;
         // only split by ':' if there is no default string value
-        if ('\'"'.indexOf(str.substr(-2, 1)) == -1) {
+        if ('\'"'.indexOf(str.slice(-2, -1)) == -1) {
             split = str.split(':');
             str = split[0];
             if (split.length == 2) {
@@ -637,7 +637,7 @@ Ox.tokenize = (function() {
                 identifier: function() {
                     var str;
                     while ((identifier + number).indexOf(source[++cursor]) > -1) {}
-                    str = source.substring(start, cursor);
+                    str = source.slice(start, cursor);
                     Ox.forEach(word, function(value, key) {
                         if (value.indexOf(str) > -1) {
                             type = key;
diff --git a/source/Ox/js/String.js b/source/Ox/js/String.js
index 9d63b156..666cdf10 100644
--- a/source/Ox/js/String.js
+++ b/source/Ox/js/String.js
@@ -48,7 +48,7 @@ Ox.ends = Ox.endsWith = function(str, sub) {
     // fixme: rename to ends
     str = str.toString();
     sub = sub.toString();
-    return str.substr(str.length - sub.length) == sub;
+    return str.slice(str.length - sub.length) == sub;
 };
 
 /*@
@@ -107,7 +107,7 @@ Ox.highlightHTML = function(html, str, classname, tags) {
             isEntity = true;
         } else if (!isTag && chr == '<') {
             Ox.forEach(tags, function(tag) {
-                if (html.substr(i + 1).match(new RegExp('^/?' + tag + '\\W'))) {
+                if (html.slice(i + 1).match(new RegExp('^/?' + tag + '\\W'))) {
                     isTag = true;
                     Ox.break();
                 }
@@ -138,10 +138,10 @@ Ox.highlightHTML = function(html, str, classname, tags) {
     });
     positions.forEach(function(position) {
         var match = '<span class="' + classname + '">'
-            + html.substr(position[0], position[1] - position[0])
+            + html.slice(position[0], position[1])
                 .replace(/(<.*?>)/g, '</span>$1<span class="' + classname + '">')
             + '</span>';
-        html = html.substr(0, position[0]) + match + html.substr(position[1]);
+        html = html.slice(0, position[0]) + match + html.slice(position[1]);
     });
     return html;
 }
@@ -180,13 +180,11 @@ Ox.pad = function(str, len, pad) {
     // fixme: slighly obscure signature
     // fixme: weird for negative numbers
     var pos = len / (len = Math.abs(len));
-    str = str.toString().substr(0, len);
+    str = str.toString().slice(0, len);
     pad = Ox.repeat(pad || '0', len - str.length);
-    str = pos == 1 ? pad + str : str + pad;
-    str = pos == 1 ?
-        str.substr(str.length - len, str.length) :
-        str.substr(0, len);
-    return str;
+    return pos == 1
+        ? (pad + str).slice(-len)
+        : (str + pad).slice(0, len);
 };
 
 /*@
@@ -209,7 +207,7 @@ Ox.parsePath = function(str) {
     return {
         pathname: matches[1] || '',
         filename: matches[2] || '',
-        extension: matches[3] ? matches[3].substr(1) : ''
+        extension: matches[3] ? matches[3].slice(1) : ''
     };
 }
 
@@ -422,7 +420,7 @@ Ox.starts = Ox.startsWith = function(str, sub) {
     // fixme: rename to starts
     str = str.toString();
     sub = sub.toString();
-    return str.substr(0, sub.length) == sub;
+    return str.slice(0, sub.length) == sub;
 };
 
 /*@
@@ -482,10 +480,10 @@ Ox.toTitleCase <f> Returns a string with capitalized words
 @*/
 Ox.toTitleCase = function(str) {
     return str.split(' ').map(function(val) {
-        var sub = val.substr(1),
+        var sub = val.slice(1),
             low = sub.toLowerCase();
         if (sub == low) {
-            val = val.substr(0, 1).toUpperCase() + low;
+            val = val.slice(0, 1).toUpperCase() + low;
         }
         return val;
     }).join(' ');
@@ -533,13 +531,13 @@ Ox.truncate = function(str, len, pad, pos) {
         left, right;
     if (strlen > len) {
         if (pos == 'left') {
-            str = pad + str.substr(padlen + strlen - len);
+            str = pad + str.slice(padlen + strlen - len);
         } else if (pos == 'center') {
             left = Math.ceil((len - padlen) / 2);
             right = Math.floor((len - padlen) / 2);
-            str = str.substr(0, left) + pad + str.substr(-right);
+            str = str.slice(0, left) + pad + str.slice(-right);
         } else if (pos == 'right') {
-            str = str.substr(0, len - padlen) + pad;
+            str = str.slice(0, len - padlen) + pad;
         }
     }
     return str;
@@ -628,7 +626,7 @@ Ox.wordwrap = function(str, len, sep, bal, spa) {
             } else {
                 // word is longer than line
                 chr = len - lines[lines.length - 1].length;
-                lines[lines.length - 1] += word.substr(0, chr);
+                lines[lines.length - 1] += word.slice(0, chr);
                 Ox.loop(chr, word.length, len, function(pos) {
                     lines.push(word.substr(pos, len));
                 });