diff --git a/examples/splitter/index.html b/examples/splitter/index.html
index 9be830c25..566136990 100644
--- a/examples/splitter/index.html
+++ b/examples/splitter/index.html
@@ -66,10 +66,6 @@
         </div>
 
         <script type="text/javascript" src="../../dist/ethers-wallet.js"></script>
-
-        <!-- This greatly improves the scrypt PBKDF performance -->
-        <script type="text/javascript" src="./setImmediate.js"></script>
-
         <script type="text/javascript">
             var submitCheck = document.getElementById('submitCheck');
             var submitSplit = document.getElementById('submitSplit');
diff --git a/examples/splitter/setImmediate.js b/examples/splitter/setImmediate.js
deleted file mode 100644
index 5abe55ccf..000000000
--- a/examples/splitter/setImmediate.js
+++ /dev/null
@@ -1,175 +0,0 @@
-(function (global, undefined) {
-    "use strict";
-
-    if (global.setImmediate) {
-        return;
-    }
-
-    var nextHandle = 1; // Spec says greater than zero
-    var tasksByHandle = {};
-    var currentlyRunningATask = false;
-    var doc = global.document;
-    var setImmediate;
-
-    function addFromSetImmediateArguments(args) {
-        tasksByHandle[nextHandle] = partiallyApplied.apply(undefined, args);
-        return nextHandle++;
-    }
-
-    // This function accepts the same arguments as setImmediate, but
-    // returns a function that requires no arguments.
-    function partiallyApplied(handler) {
-        var args = [].slice.call(arguments, 1);
-        return function() {
-            if (typeof handler === "function") {
-                handler.apply(undefined, args);
-            } else {
-                (new Function("" + handler))();
-            }
-        };
-    }
-
-    function runIfPresent(handle) {
-        // From the spec: "Wait until any invocations of this algorithm started before this one have completed."
-        // So if we're currently running a task, we'll need to delay this invocation.
-        if (currentlyRunningATask) {
-            // Delay by doing a setTimeout. setImmediate was tried instead, but in Firefox 7 it generated a
-            // "too much recursion" error.
-            setTimeout(partiallyApplied(runIfPresent, handle), 0);
-        } else {
-            var task = tasksByHandle[handle];
-            if (task) {
-                currentlyRunningATask = true;
-                try {
-                    task();
-                } finally {
-                    clearImmediate(handle);
-                    currentlyRunningATask = false;
-                }
-            }
-        }
-    }
-
-    function clearImmediate(handle) {
-        delete tasksByHandle[handle];
-    }
-
-    function installNextTickImplementation() {
-        setImmediate = function() {
-            var handle = addFromSetImmediateArguments(arguments);
-            process.nextTick(partiallyApplied(runIfPresent, handle));
-            return handle;
-        };
-    }
-
-    function canUsePostMessage() {
-        // The test against `importScripts` prevents this implementation from being installed inside a web worker,
-        // where `global.postMessage` means something completely different and can't be used for this purpose.
-        if (global.postMessage && !global.importScripts) {
-            var postMessageIsAsynchronous = true;
-            var oldOnMessage = global.onmessage;
-            global.onmessage = function() {
-                postMessageIsAsynchronous = false;
-            };
-            global.postMessage("", "*");
-            global.onmessage = oldOnMessage;
-            return postMessageIsAsynchronous;
-        }
-    }
-
-    function installPostMessageImplementation() {
-        // Installs an event handler on `global` for the `message` event: see
-        // * https://developer.mozilla.org/en/DOM/window.postMessage
-        // * http://www.whatwg.org/specs/web-apps/current-work/multipage/comms.html#crossDocumentMessages
-
-        var messagePrefix = "setImmediate$" + Math.random() + "$";
-        var onGlobalMessage = function(event) {
-            if (event.source === global &&
-                typeof event.data === "string" &&
-                event.data.indexOf(messagePrefix) === 0) {
-                runIfPresent(+event.data.slice(messagePrefix.length));
-            }
-        };
-
-        if (global.addEventListener) {
-            global.addEventListener("message", onGlobalMessage, false);
-        } else {
-            global.attachEvent("onmessage", onGlobalMessage);
-        }
-
-        setImmediate = function() {
-            var handle = addFromSetImmediateArguments(arguments);
-            global.postMessage(messagePrefix + handle, "*");
-            return handle;
-        };
-    }
-
-    function installMessageChannelImplementation() {
-        var channel = new MessageChannel();
-        channel.port1.onmessage = function(event) {
-            var handle = event.data;
-            runIfPresent(handle);
-        };
-
-        setImmediate = function() {
-            var handle = addFromSetImmediateArguments(arguments);
-            channel.port2.postMessage(handle);
-            return handle;
-        };
-    }
-
-    function installReadyStateChangeImplementation() {
-        var html = doc.documentElement;
-        setImmediate = function() {
-            var handle = addFromSetImmediateArguments(arguments);
-            // Create a <script> element; its readystatechange event will be fired asynchronously once it is inserted
-            // into the document. Do so, thus queuing up the task. Remember to clean up once it's been called.
-            var script = doc.createElement("script");
-            script.onreadystatechange = function () {
-                runIfPresent(handle);
-                script.onreadystatechange = null;
-                html.removeChild(script);
-                script = null;
-            };
-            html.appendChild(script);
-            return handle;
-        };
-    }
-
-    function installSetTimeoutImplementation() {
-        setImmediate = function() {
-            var handle = addFromSetImmediateArguments(arguments);
-            setTimeout(partiallyApplied(runIfPresent, handle), 0);
-            return handle;
-        };
-    }
-
-    // If supported, we should attach to the prototype of global, since that is where setTimeout et al. live.
-    var attachTo = Object.getPrototypeOf && Object.getPrototypeOf(global);
-    attachTo = attachTo && attachTo.setTimeout ? attachTo : global;
-
-    // Don't get fooled by e.g. browserify environments.
-    if ({}.toString.call(global.process) === "[object process]") {
-        // For Node.js before 0.9
-        installNextTickImplementation();
-
-    } else if (canUsePostMessage()) {
-        // For non-IE10 modern browsers
-        installPostMessageImplementation();
-
-    } else if (global.MessageChannel) {
-        // For web workers, where supported
-        installMessageChannelImplementation();
-
-    } else if (doc && "onreadystatechange" in doc.createElement("script")) {
-        // For IE 6–8
-        installReadyStateChangeImplementation();
-
-    } else {
-        // For older browsers
-        installSetTimeoutImplementation();
-    }
-
-    attachTo.setImmediate = setImmediate;
-    attachTo.clearImmediate = clearImmediate;
-}(typeof self === "undefined" ? typeof global === "undefined" ? this : global : self));
diff --git a/examples/wallet/index.html b/examples/wallet/index.html
index ad88a5830..1a404f74b 100644
--- a/examples/wallet/index.html
+++ b/examples/wallet/index.html
@@ -161,10 +161,6 @@
         </div>
 
         <script type="text/javascript" src="../../dist/ethers-wallet.js"></script>
-
-        <!-- This greatly improves the scrypt PBKDF performance -->
-        <script type="text/javascript" src="./setImmediate.js"></script>
-
         <script type="text/javascript">
             function setEnter(source, target) {
                 source.onkeyup = function(e) {
diff --git a/examples/wallet/setImmediate.js b/examples/wallet/setImmediate.js
deleted file mode 100644
index 5abe55ccf..000000000
--- a/examples/wallet/setImmediate.js
+++ /dev/null
@@ -1,175 +0,0 @@
-(function (global, undefined) {
-    "use strict";
-
-    if (global.setImmediate) {
-        return;
-    }
-
-    var nextHandle = 1; // Spec says greater than zero
-    var tasksByHandle = {};
-    var currentlyRunningATask = false;
-    var doc = global.document;
-    var setImmediate;
-
-    function addFromSetImmediateArguments(args) {
-        tasksByHandle[nextHandle] = partiallyApplied.apply(undefined, args);
-        return nextHandle++;
-    }
-
-    // This function accepts the same arguments as setImmediate, but
-    // returns a function that requires no arguments.
-    function partiallyApplied(handler) {
-        var args = [].slice.call(arguments, 1);
-        return function() {
-            if (typeof handler === "function") {
-                handler.apply(undefined, args);
-            } else {
-                (new Function("" + handler))();
-            }
-        };
-    }
-
-    function runIfPresent(handle) {
-        // From the spec: "Wait until any invocations of this algorithm started before this one have completed."
-        // So if we're currently running a task, we'll need to delay this invocation.
-        if (currentlyRunningATask) {
-            // Delay by doing a setTimeout. setImmediate was tried instead, but in Firefox 7 it generated a
-            // "too much recursion" error.
-            setTimeout(partiallyApplied(runIfPresent, handle), 0);
-        } else {
-            var task = tasksByHandle[handle];
-            if (task) {
-                currentlyRunningATask = true;
-                try {
-                    task();
-                } finally {
-                    clearImmediate(handle);
-                    currentlyRunningATask = false;
-                }
-            }
-        }
-    }
-
-    function clearImmediate(handle) {
-        delete tasksByHandle[handle];
-    }
-
-    function installNextTickImplementation() {
-        setImmediate = function() {
-            var handle = addFromSetImmediateArguments(arguments);
-            process.nextTick(partiallyApplied(runIfPresent, handle));
-            return handle;
-        };
-    }
-
-    function canUsePostMessage() {
-        // The test against `importScripts` prevents this implementation from being installed inside a web worker,
-        // where `global.postMessage` means something completely different and can't be used for this purpose.
-        if (global.postMessage && !global.importScripts) {
-            var postMessageIsAsynchronous = true;
-            var oldOnMessage = global.onmessage;
-            global.onmessage = function() {
-                postMessageIsAsynchronous = false;
-            };
-            global.postMessage("", "*");
-            global.onmessage = oldOnMessage;
-            return postMessageIsAsynchronous;
-        }
-    }
-
-    function installPostMessageImplementation() {
-        // Installs an event handler on `global` for the `message` event: see
-        // * https://developer.mozilla.org/en/DOM/window.postMessage
-        // * http://www.whatwg.org/specs/web-apps/current-work/multipage/comms.html#crossDocumentMessages
-
-        var messagePrefix = "setImmediate$" + Math.random() + "$";
-        var onGlobalMessage = function(event) {
-            if (event.source === global &&
-                typeof event.data === "string" &&
-                event.data.indexOf(messagePrefix) === 0) {
-                runIfPresent(+event.data.slice(messagePrefix.length));
-            }
-        };
-
-        if (global.addEventListener) {
-            global.addEventListener("message", onGlobalMessage, false);
-        } else {
-            global.attachEvent("onmessage", onGlobalMessage);
-        }
-
-        setImmediate = function() {
-            var handle = addFromSetImmediateArguments(arguments);
-            global.postMessage(messagePrefix + handle, "*");
-            return handle;
-        };
-    }
-
-    function installMessageChannelImplementation() {
-        var channel = new MessageChannel();
-        channel.port1.onmessage = function(event) {
-            var handle = event.data;
-            runIfPresent(handle);
-        };
-
-        setImmediate = function() {
-            var handle = addFromSetImmediateArguments(arguments);
-            channel.port2.postMessage(handle);
-            return handle;
-        };
-    }
-
-    function installReadyStateChangeImplementation() {
-        var html = doc.documentElement;
-        setImmediate = function() {
-            var handle = addFromSetImmediateArguments(arguments);
-            // Create a <script> element; its readystatechange event will be fired asynchronously once it is inserted
-            // into the document. Do so, thus queuing up the task. Remember to clean up once it's been called.
-            var script = doc.createElement("script");
-            script.onreadystatechange = function () {
-                runIfPresent(handle);
-                script.onreadystatechange = null;
-                html.removeChild(script);
-                script = null;
-            };
-            html.appendChild(script);
-            return handle;
-        };
-    }
-
-    function installSetTimeoutImplementation() {
-        setImmediate = function() {
-            var handle = addFromSetImmediateArguments(arguments);
-            setTimeout(partiallyApplied(runIfPresent, handle), 0);
-            return handle;
-        };
-    }
-
-    // If supported, we should attach to the prototype of global, since that is where setTimeout et al. live.
-    var attachTo = Object.getPrototypeOf && Object.getPrototypeOf(global);
-    attachTo = attachTo && attachTo.setTimeout ? attachTo : global;
-
-    // Don't get fooled by e.g. browserify environments.
-    if ({}.toString.call(global.process) === "[object process]") {
-        // For Node.js before 0.9
-        installNextTickImplementation();
-
-    } else if (canUsePostMessage()) {
-        // For non-IE10 modern browsers
-        installPostMessageImplementation();
-
-    } else if (global.MessageChannel) {
-        // For web workers, where supported
-        installMessageChannelImplementation();
-
-    } else if (doc && "onreadystatechange" in doc.createElement("script")) {
-        // For IE 6–8
-        installReadyStateChangeImplementation();
-
-    } else {
-        // For older browsers
-        installSetTimeoutImplementation();
-    }
-
-    attachTo.setImmediate = setImmediate;
-    attachTo.clearImmediate = clearImmediate;
-}(typeof self === "undefined" ? typeof global === "undefined" ? this : global : self));
diff --git a/package.json b/package.json
index f0d8b0a4f..19c75e6ba 100644
--- a/package.json
+++ b/package.json
@@ -13,6 +13,7 @@
     "inherits": "2.0.1",
     "pbkdf2": "3.0.4",
     "rlp": "2.0.0",
+    "setimmediate": "1.0.4",
     "scrypt-js": "2.0.2",
     "uuid": "2.0.1",
     "xmlhttprequest": "1.8.0"