Marko vs Ember

Marko consistently outperforms other alternatives in code benchmarks, both on rendering speed and compilation time.

Custom tags provide a simple mechanism for embedding more complex components into a template by extending the HTML grammar with support for new tags. For example:

<div>
    <say-hello name="World"/>
</div>

Custom tags are easy to create since they just map to a JavaScript "renderer" function as shown below:

module.exports = function sayHelloRenderer(input, out) {
    out.write('Hello ' + input.name + '!');
}

Custom tags support nested content:

<fancy-overlay title="My Title">
    This will be the body content of the overlay
</fancy-overlay>

Custom tags can also have parent/child relationships to support more complex use cases such a "tabs" component with nested "tab" components:

<fancy-tabs>
    <fancy-tabs:tab label="Home">
        Content for Home
    </fancy-tabs:tab>
    <fancy-tabs:tab label="Profile">
        Content for Profile
    </fancy-tabs:tab>
    <fancy-tabs:tab label="Messages">
        Content for Messages
    </fancy-tabs:tab>
</fancy-tabs>

Streaming allows progressive HTML rendering and reduces time to first byte.

Marko supports both server-side and client-side rendering.

Marko Widgets allows UI components (rendering + behavior) to be built using Marko.

Avoids ugly globals and "named" templates.

var template = require('./template.marko');
var html = template.renderSync({name: 'Frank'});

Marko makes additional asynchronous calls after the view rendering has begun.

Easy Integration with Express and Node

The documentation is extensive and very helpful. It also contains several sample applications which are very useful.

JavaScript expressions can be executed inside the templates.

Marko has a HTML-like syntax which should be easy to read and understand for everyone who has even minimal experience in web development.

It is easy to get up to speed and understand what is going on in a very short period of time.

Marko's compiled templates are usually very small, as proven by benchmarks.

To prevent regressions, Marko includes a full suite of tests. The testing harness renders a collection of templates and does an exact string comparison to make sure that the tests rendered exactly as expected. There are also API tests, and negative tests to make sure that errors are reported in a friendly way.

To run tests:
git clone https://github.com/marko-js/marko
cd marko
npm install
npm test

Error messages come in an easy to read and friendly format, with valid stack traces and file formats of the file(s) which brought the error(s).

The Concise syntax type lets you write Marko with a Jade-like indentation based syntax, and the Mixed mode lets you combine in regular HTML-style syntax.

Marko's development community is rather small compared to other frameworks but community is well mannered and active. You can chat with the core development team using gitter.im

Ember already defines the general application structure and organization for you. This was done to prevent developers from making mistakes which would needlessly over-complicate their application. While it's still possible to go out of these practices forced to developers by the Ember authors, you still have to go out of your way to force them.

Ember-CLI is a very useful tool. With just a couple of commands it scaffolds the code, installs dependencies and finally compiles everything itself. It's very useful to quickstart an Ember project.

Ember's preferred templating language is Handlebars. This is mainly because Handlebars is a logic-less templating language and Ember tries to keep it's logic outside the view.

Another reason why Ember benefits from Handlebars is mostly aesthetic as Handlebar's clean syntax makes for easier to read and understand templates.

Finally, Handlebars templates are compiled instead of interpreted, which means that they are much faster to load.

Ember follows the philosophy of "convention over configuration" meaning that it already has almost everything configured for you, so you just have to start coding and developing your project right away.

Ember is practically a complete full-stack front-end framework. It comes with it's own asset pipeline, router, services etc...

The Ember Guides are well structured and very well written. The API documentation is also fantastic.

Most of Ember's components come from the Ember Object Model. It's the basis for views, controllers, models and even the framework itself. This means that the framework is extremely consistent since almost every component shares the same core functionalities and properties since they are all derived from the same object.

Route handlers for the URLs can see a wide range of possible application states, asynchronous logic in the router makes sure of Promises. And implementing makes sense.

It batches bindings and DOM updates to increase performance; if similar tasks are added to a batch, the browser would only need to process them in one single go, as compared to re-computing for each task one at a time.

Ember's API are really easy to understand and work with. It has methods which allow you to harness complicated functionalities in an easy to understand way.

Ember's new router need much less boilerplate code that it previously did.

Ember also has a debugging tool called Ember Inspector which is used for debugging the client side of your app.

You can use any of jQuery’s features.

EmberJS provides with an extremely handy feature of advanced bindings. With this you can not only set the path to the binding value in your app but also set in which direction you want the changes to propagate to (oneway, single, multiple etc).

Promises represent an eventual state in asynchronous logic. Having promises everywhere (almost) means you could write simple and modular code, using almost any API that Ember provides.

Having custom properties in your templates is itself a huge plus but having custom computed properties is an even greater benefit, since now you can code your custom function as a property and call it from your template. Hence rendering your page exactly according to your needs.

Ember comes with built-in routing capabilities. There's no need to install third-party plugins to be able to use routes.

If you've used handlebars (Ember.js's templating is powered by HandleBars) helper tags in your code (like {{#each}}) you won't have to worry about updating your template each time you add/remove data from your page, Handlebars will auto update your template for you.