diff --git a/lib/execjs/support/node_runner.js b/lib/execjs/support/node_runner.js
index 2987d9f..4c8cacf 100644
--- a/lib/execjs/support/node_runner.js
+++ b/lib/execjs/support/node_runner.js
@@ -1,20 +1,17 @@
-(function(program, execJS) { execJS(program) })(function(global, process, module, exports, require, console, setTimeout, setInterval, clearTimeout, clearInterval, setImmediate, clearImmediate) { #{source}
-}, function(program) {
+(function(execJS) { execJS() })(function() {
+  var source = #{::JSON.dump(source)};
+  source = "(function(){"+ source + "})()";
+
   var output, print = function(string) {
     process.stdout.write('' + string);
   };
   try {
-    var __process__ = process;
-    delete this.process;
-    delete this.console;
-    delete this.setTimeout;
-    delete this.setInterval;
-    delete this.clearTimeout;
-    delete this.clearInterval;
-    delete this.setImmediate;
-    delete this.clearImmediate;
+    var program = function(){
+      var vm = require('vm');
+      var context = vm.createContext();
+      return vm.runInNewContext(source, context, "(execjs)");
+    }
     result = program();
-    this.process = __process__;
     if (typeof result == 'undefined' && result !== null) {
       print('["ok"]');
     } else {
@@ -25,7 +22,6 @@
       }
     }
   } catch (err) {
-    this.process = __process__;
     print(JSON.stringify(['err', '' + err, err.stack]));
   }
 });