diff --git a/src/app.js b/src/app.js
index a3132352d2..017e1d3b05 100644
--- a/src/app.js
+++ b/src/app.js
@@ -241,9 +241,9 @@ var run = function() {
 		return $('<li class="file"><span class="name">'+name+'</span><span class="remove"><i class="fa fa-close"></i></span></li>');
 	}
 
-	$filesWrapper = $('.files-wrapper');
-	$scrollerRight = $('.scroller-right');
-	$scrollerLeft = $('.scroller-left');
+	var $filesWrapper = $('.files-wrapper');
+	var $scrollerRight = $('.scroller-right');
+	var $scrollerLeft = $('.scroller-left');
 
 	function widthOfList (){
 		var itemsWidth = 0;
diff --git a/src/app/compiler.js b/src/app/compiler.js
index 11d35dbafd..2f0e800019 100644
--- a/src/app/compiler.js
+++ b/src/app/compiler.js
@@ -161,6 +161,7 @@ function Compiler(web3, editor, handleGithubCall, outputField, hidingRHP, update
     }
     var importRegex = /^\s*import\s*[\'\"]([^\'\"]+)[\'\"];/g;
     var reloop = false;
+    var githubMatch;
     do {
       reloop = false;
       for (var fileName in files) {
diff --git a/src/app/renderer.js b/src/app/renderer.js
index 90640a9286..b3a8700b5b 100644
--- a/src/app/renderer.js
+++ b/src/app/renderer.js
@@ -121,7 +121,7 @@ function Renderer(web3, editor, compiler, updateFiles) {
 
     var $contractOutput = dapp.render();
 
-    $txOrigin = $('#txorigin');
+    var $txOrigin = $('#txorigin');
 
     function renderAccounts(err, accounts) {
       if (err)
@@ -188,13 +188,14 @@ function Renderer(web3, editor, compiler, updateFiles) {
   var formatGasEstimates = function(data) {
     var gasToText = function(g) { return g === null ? 'unknown' : g; }
     var text = '';
+    var fun;
     if ('creation' in data)
       text += 'Creation: ' + gasToText(data.creation[0]) + ' + ' + gasToText(data.creation[1]) + '\n';
     text += 'External:\n';
-    for (var fun in data.external)
+    for (fun in data.external)
       text += '  ' + fun + ': ' + gasToText(data.external[fun]) + '\n';
     text += 'Internal:\n';
-    for (var fun in data.internal)
+    for (fun in data.internal)
       text += '  ' + fun + ': ' + gasToText(data.internal[fun]) + '\n';
     return text;
   };
diff --git a/src/universal-dapp.js b/src/universal-dapp.js
index f44695b801..0122aab6fb 100644
--- a/src/universal-dapp.js
+++ b/src/universal-dapp.js
@@ -97,7 +97,7 @@ UniversalDApp.prototype.render = function () {
             this.$el.append(this.renderOutputModifier(this.contracts[c].name, $contractEl));
         }
     }
-    $legend = $('<div class="legend" />')
+    var $legend = $('<div class="legend" />')
         .append( $('<div class="attach"/>').text('Attach') )
         .append( $('<div class="transact"/>').text('Transact') )
         .append( $('<div class="call"/>').text('Call') );
@@ -183,13 +183,14 @@ UniversalDApp.prototype.getInstanceInterface = function (contract, address, $tar
             $instance.toggleClass('hide');
         });
 
-        $events = $('<div class="events"/>');
+        var $events = $('<div class="events"/>');
 
         var parseLogs = function(err,response) {
             if (err)
                 return;
 
-            $event = $('<div class="event" />');
+            var $event = $('<div class="event" />');
+
             var $close = $('<div class="udapp-close" />');
             $close.click( function(){ $event.remove(); } );
 
@@ -562,8 +563,9 @@ UniversalDApp.prototype.runTx = function( data, args, cb) {
         }
     }
 
+    var tx;
     if (!this.vm) {
-        var tx = {
+        tx = {
             from: self.options.getAddress ? self.options.getAddress() : web3.eth.accounts[0],
             to: to,
             data: data,
@@ -583,7 +585,7 @@ UniversalDApp.prototype.runTx = function( data, args, cb) {
         try {
             var address = this.options.getAddress ? this.options.getAddress() : this.getAccounts()[0];
             var account = this.accounts[address];
-            var tx = new EthJSTX({
+            tx = new EthJSTX({
                 nonce: new Buffer([account.nonce++]), //@todo count beyond 255
                 gasPrice: 1,
                 gasLimit: 3000000000, //plenty