Raible Designs

A Spectacular Trip to Stockholm and Madrid

When I travel in the winter, it's usually to ski resorts or client sites, not to conferences. However, when the Mattias Karlsson invited me to speak at Jfokus, I jumped at the opportunity. That same day in Antwerp, Sergi Almar asked me to speak at Spring I/O. Turns out, both conferences were in the same week so we worked out the logistics of traveling to Stockholm and Madrid and got ready for a spectacular trip.

Trish and I started our journey two weeks ago by flying over the top of world, connecting through Seattle and Reykjavik (Iceland) before arriving in Stockholm on Monday afternoon. We took the bullet train from the airport to downtown and walked a couple blocks to the conference venue/hotel. We checked in, relaxed, then met a bunch of folks a few hours later to go to the speaker's dinner at F12.

On Tuesday, I attended quite a few sessions at the conference, took and nap and delivered my Comparing JVM Web Frameworks talk at 17:00. The Atlassian Bar opened after my talk concluded and we enjoyed some tasty beverages while talking tech with new and old friends. James Ward's Cloud BOF started at 8 and we enjoyed the beer and banter before heading out to the local Sports Bar. We scared the bar's proprietors with our hunger and thirst at such a late hour, but they served us anyway.

On Wednesday, I got woken up by the hotel's housekeeping at 9:52 and I had to be on stage at 10:10. I got dressed and downstairs as fast as I could and put the final touches on my presentation as people were filing in the room. I opened my talk with, "You ever had one of those morning where the housekeeping woke you up and you had to be on stage 10 minutes later?"

The conference ended that day, but Trish and I extended it a bit by going to the Scala Stockholm Meetup and walking around the city to capture some night photos. I wrote up a blog post about my presentations and Jfokus the next morning and Trish posted both her Jfokus and Stockholm pictures to Flickr. Below are some of my favorite pictures of Sweden.

On Thursday, we traveled to Madrid for Spring I/O. We arrived at sunset and met up with Josh Long and his Dad for a ride to our hotel. Trish went to high school in Puerto Rico and got to show of her Spanish skills when she helped the driver find the hotel. I spoke on Friday morning and we spent the rest of the weekend taking photos and enjoying Carnival. We had a great hotel in the heart of Madrid and could walk to almost all the historic sites.

It was great seeing Trish in Madrid. Her Spanish was excellent and I felt like I had a personal tour guide the whole time. Her pictures show the weather was beautiful and the sites, amazing.

You can see all of Trish's Madrid photos on Flickr. I also published mine in a Stockholm and Madrid 2012 album.

For more of Trish's photos from our world travels, see McGinity Photo's World Gallery.

Comparing Web Frameworks and HTML5 with Play Scala at Jfokus 2012

Stockholm seems a lot like Denver this time of year. Cold, snowy and beautiful. Trish and I arrived in Stockholm (Sweden) on Monday for the Jfokus conference and we're traveling to Madrid today for the Spring I/O conference. I was invited to Jfokus within minutes of delivering my HTML5 with Play Scala talk at Devoxx.

Both the Jfokus and Spring I/O Organizers were interested in my Comparing JVM Web Frameworks talk, so I updated it to reflect my latest thoughts. First of all, I mentioned that there's a lot of great frameworks out there and I think the reason people are so apprehensive to choose one is because they've chosen badly at one point. This might've been Struts back in the day (even thought it was one of the best frameworks at the time) or it might be because a vendor talked them into it. However, if you look at the modern JVM frameworks today, you should be able to see that they're all pretty awesome.

I mentioned how I think Web developers should know JavaScript and CSS. If you're a Java developer and you call yourself a web developer, you're letting your framework do too much of the work for you. I mentioned Rich Manalang's Modern Principles in Web Development, where he talks about his core web development principles.

• Designing for mobile first (even if you’re not building a mobile app)
• Build only single page apps
• Create and use your own REST API
• “Sex sells” applies to web apps

I've found these principles to be true in my own experience and suggested that if you want to be a web developer, the frameworks you might want to learn are not traditional JVM web frameworks, but rather client-side MVC frameworks. For those Java developers that don't want to be web developers, I suggest they strengthen their services development knowledge by reading Hot to GET a Cup of Coffee.

I delivered my 2nd presentation on HTML5 with Play Scala, CoffeeScript and Jade on Wednesday morning. This talk is one of my favorites and I prepared for it over the last several weeks by adding JSON CRUD Services and SecureSocial to my HTML5 Fitness Tracking application. Right before we left for Jfokus, I was able to get everything to work, but didn't spend as much time as I'd like working on the mobile client. If this talk gets accepted for Devoxx France, I plan on spending most of my time enhancing the mobile client. After my latest experience developing, I can see how Rich's first principle (above) makes a lot of sense.

Below is my presentation for this talk. Of course, it's on Slideshare and downloadable as a PDF.

I also updated the Developing Play More demo video to show my latest efforts.

Delivering these talks at Jfokus was a lot of fun. Yes, it was a lot of work and stress to prepare them. However, I also learned a lot creating them and I hope the audience benefitted from that.

The conference itself was incredible. I got to meet Peter Hilton and Helena Hjertén as I was registering. The speaker's dinner at F12 was off-the-hook good and I had the pleasure of finally meeting Rickard Öberg.

I also attended some fantastic presentations, including Peter Hilton's Play Framework 2.0, Bodil Stokke's CoffeeScript: JavaScript without the Fail, Pamela Fox's Client-side Storage and Heiko Seeberger's Scala in Action. I don't know if Heiko has published any slides, but I'm guessing not since most of his presentation was live coding.

I have lots of good memories from Jfokus. Many thanks to Mattias for inviting me!

Play Framework 2.0 with Peter Hilton at Jfokus

This week, I'm at Jfokus in Stockholm, Sweden. After a fun speaker's dinner last night, I got up this morning and polished up my presentations and demo before attending the conference. The first session I attended was Peter Hilton's Play Framework 2.0 presentation. Below are my notes from this talk.

Peter is a Senior Web Developer, not a Java Developer. His first slide states the following:

"Play brings type safe high-productivity web development to the JVM."

New features in Play 2.0: type-safety, template syntax, compile-time checking and asynchronous HTTP programming. Java, Scala - the language you use is less important than the fact that Play is a web framework. It's a full-stack framework and has everything you need out-of-the-box to build a web application. Play focuses on HTTP and doesn't try to hide it. It's designed by web developers for web developers.

With Play, the Back button just works. Your web framework shouldn't break the first button on your browser's toolbar. The Reload button also works: make a change, hit reload and your changes (even in Scala classes) are shown. You design the URLs and you can use "clean" URLs. DX (Developer eXperience) is Peter's new term. Usability matters: as a developer, you deserve a framework that provides a good experience.

Play doesn't fight HTTP or the browser. It's stateless and HTTP-centric. A few years ago, it seemed like a good idea to try and keep state on the server. It sounded like a good idea, but in practice, it's a really bad idea - especially for things like the back button. Play matches the web's stateless HTTP architecture.

As a Java EE developer, PHP and Rails developers have been laughing at us for years. Like Father Christmas, Peter's heard of class-reloading, but he hasn't actually seen it. Code reloading is the most important part of DX and about achieving high-productivity in web development.

URLs want to be loved too. REST architecture isn't just for web service APIs. When you have clean URLs, you can tweet them, post them and email them.

"You would need to be a super-hero to successfully use some web frameworks." They show you a blank screen in the browser and you have to look at your console's stack trace to figure it out. With Play, the error is shown in your browser and you can see the exact line it happens on.

In Play 1.x, there was a lot of magic and a lot of bytecode enhancement at runtime. This allowed the API to be a lot nicer than traditional Java APIs. However, it caused issues when users viewed the enhanced source and it also caused issues in IDEs. With Play 2.0, the framework itself is implemented in Scala. Scala removes the need for so much bytecode enhancement. There is less 'magic' and strangeness in the API. The code you see in the IDE is the code that runs. Scala source code is not necessarily harder to read. 1.x had some pretty hairy Java code, and you could tell when you dug into it. Especially when you were deep into the source code and saw that a lot of the comments were in French.

Play 2.0's template system is based on Scala. It's similar to the lightweight template syntax in Play 1.x. Templates are compiled into class files for run-time speed. For example:

@(products: Seq[Product])

<ul>
@for(product <- products) {
  <li>@product.name</li>
}
</ul>

@summary(products)

We used to think XML-based templates were great, but it turns out it's a terrible idea. Mostly because you end up having to invent an expression language to create valid XML (to avoid putting XML in your HTML attributes). With Play 2.0's templates, you can define tags in your templates as regular Scala methods.

@display(product: models.Product) ={
 <a href="@routes.Product.details(product.id)">@product.name</a> 
}

@for(product <- products) {
  @display(product)
}

The compile-time checking in Play 2.0 is not just for Java and Scala classes. It also compiles your HTTP routes file (which maps requests to controller actions). Furthermore, it compiles your templates, JavaScript files (using Google Closure Compiler), CoffeeScript files and LESS stylesheets.

Play supports modern web development. It's designed to work with HTML5, but there's no constraints on HTML output. It's front-end developer friendly and has great DX. UI components belong in the client, e.g. jQuery UI. It also has built-in support for improvements to CSS (LESS) and JavaScript (CoffeeScript).

A few years ago, it seemed like a really good idea to hide JavaScript from the web developer. Web frameworks used to say "You don't need to see the JavaScript or the HTML, we'll handle generating your components for you." Now, if you're building a web application and you don't know any jQuery, you doing it the hard way. You should learn how to work with front-end developers or learn how to do it yourself. And make sure your web framework allows this sort of development.

The future of web programming is asynchronous. You'll perform simultaneous web service requests. You'll process streams of data, instead of filling up memory or disk. You'll publish real-time data and have predictable and minimal resource consumption. In the long term, this changes everything. The future of the web is real-time and asynchronous. With Play 2.0, it's not just another feature, it's a fundamental aspect of the architecture. Play's internal architecture uses a reactive model based on Iteratee IO.

In summary, use Play 2, use HTML5, deploy to the Cloud. There's two forthcoming books on Play (both from Manning) and Play 2.0 RC1 will be released today.

I think Peter did a good job of summarizing the new features in Play 2.0, especially how templates work. I enjoyed his emphasis on HTTP and how Play leverages the browser (back, reload and as a console). I liked his humorous speaking style, and agree with his emphasis that client-side development skills are important for modern web applications. I think Play 2.0 is making a big bet on Scala and asynchronous programming, but if they live up to the hype, it should be a very enjoyable web framework to develop with.

Secure JSON Services with Play Scala and SecureSocial

Last November, I traveled to Antwerp to speak at Devoxx. After my talk on HTML5 with Play Scala, Mattias Karlsson approached me and we had a chat about doing the same talk at Jfokus in Stockholm. I agreed and we began talking details after Trish and I returned to the US.

I wrote this article on a plane between Denver and Seattle and will be hopping over the North Pole to Stockholm via Iceland tonight. For the past couple of weeks, I've been updating my Play More! HTML5/mobile app to add some new features. Most notably, I wanted to upgrade to Play 2.0, create JSON services and add authentication.

Upgrading to Play 2.0
My attempt to upgrade to Play 2.0 involved checking out the source from GitHub, building and installing the RC1 snapshot. As I tried to upgrade my app and started getting failed imports, I turned to the internet (specifically StackOverflow) to see if it was a good idea. The first answer for that question suggested I stay with 1.x.

If it's a critical project, to be finished before next March 2012, I would go with Play 1.x. If it's a less important project, which could be delayed, and that in any case won't be released before March 2012, try Play 2.0.

While I didn't plan on releasing Play More! before Jfokus, I decided upgrading didn't add a whole lot to the talk. Also, I couldn't find a Play Scala 0.9.1 to Play 2.0 upgrade guide and I didn't have enough time to create one. So I decided to stick with Play 1.2.4 and add some JSON services for my iPhone client.

JSON Servers
I found Manuel Bernhardt's Play! Scala and JSON. This led me to Jerkson, built by the now infamous @coda. I was able to easily get things working fairly quickly and wrote the following WorkoutService.scala:

package controllers.api

import play.mvc.Controller
import models._
import com.codahale.jerkson.Json._

object WorkoutService extends Controller {

  def workouts = {
    response.setContentTypeIfNotSet("application/json")
    generate(Workout.find().list())
  }
  def edit(id: Long) = {
    generate(Workout.byIdWithAthleteAndComments(id))
  }

  def create() = {
    var workout = params.get("workout", classOf[Workout])
    Workout.create(workout)
  }

  def save(id: Option[Long]) = {
    var workout = params.get("workout", classOf[Workout])
    Workout.update(workout)
  }

  def delete(id: Long) = {
    Workout.delete("id={id}").on("id" -> id).executeUpdate()
  }
}

Next, I added routes for my new API to conf/routes:

GET     /api/workouts               api.WorkoutService.workouts
GET     /api/workout/{id}           api.WorkoutService.edit
POST    /api/workout                api.WorkoutService.create
PUT     /api/workout/{id}           api.WorkoutService.save
DELETE  /api/workout/{id}           api.WorkoutService.delete

Then I created an ApiTest.scala class that verifies the first method works as expected.

import play.test.FunctionalTest
import play.test.FunctionalTest._
import org.junit._

class ApiTests extends FunctionalTest {
  
    @Test
    def testGetWorkouts() {
        var response = GET("/api/workouts");
        assertStatus(200, response);
        assertContentType("application/json", response)
        println(response.out)
    }
}

I ran "play test", opened my browser to http://localhost:9000/@tests and clicked ApiTests -> Start to verify it worked. All the green made me happy.

Finally, I wrote some CoffeeScript and jQuery to allow users to delete workouts and make sure delete functionality worked.

$('#delete').click ->
  $.ajax
    type: 'POST'
    url: $(this).attr('rel')
    error: ->
      alert('Delete failed, please try again.')
    success: (data) ->
      location.href = "/more"

I was very impressed with how easy Play made it to create JSON services and I smiled as my CoffeeScript skills got a refresher.

The Friday before we left for Devoxx, I saw the module registration request for SecureSocial.

SecureSocial with Play Scala
From SecureSocial's README:

In other words, it sounded like a dream come true and I resolved to try it once I found the time. That time found me last Monday evening and I sent a direct message to @jaliss (the module's author) via Twitter.

Does Secure Social work with Play Scala? I'd like to use it in my Play More! project.

Jorge responded 16 minutes later saying that he hadn't used Play Scala and he'd need to do some research. At 8 o'clock that night (1.5 hours after my original DM), Jorge had a sample working and emailed it to me. 10 minutes later I was adding a Secure trait to my project.

package controllers

import play.mvc._
import controllers.securesocial.SecureSocial

/*
 * @author Jorge Aliss <[email protected]> of Secure Social fame.
 */
trait Secure {
  self: Controller =>

  @Before def checkAccess() {
    SecureSocial.DeadboltHelper.beforeRoleCheck()
  }

  def currentUser = {
    SecureSocial.getCurrentUser
  }
}

I configured Twitter and Username + Password as my providers by adding the following to conf/application.conf.

securesocial.providers=twitter,userpass

I also had to configure a number of securesocial.twitter.* properties. Next, I made sure my routes were aware of SecureSocial by adding the following to the top of conf/routes:

  *       /auth               module:securesocial

Then I specified it as a dependency in conf/dependencies.yml and ran "play deps".

    - play -> securesocial 0.2.4

After adding "with Secure" to my Profile.scala controller, I tried to access its route and was prompted to login. Right off the bat, I was shown an error about a missing jQuery 1.5.2 file in my "javascripts" folder, so I added it and rejoiced when I was presented with a login screen. I had to add the app on Twitter to use its OAuth servers, but I was pumped when both username/password authentication worked (complete with signup!) as well as Twitter.

The only issue I ran into with SecureSocial was that it didn't find the default implementation of SecureSocial's UserService.Service when running in prod mode. I was able to workaround this by adding a SecureService.scala implementation to my project and coding it to talk to my Athlete model. I didn't bother to hook in creating a new user when they logged in from Twitter, but that's something I'll want to do in the future. I was also pleased to find out customizing SecureSocial's views was a breeze. I simply copied them from the module into my app's views and voila!

package services

import play.db.anorm.NotAssigned
import play.libs.Codec
import collection.mutable.{SynchronizedMap, HashMap}
import models.Athlete
import securesocial.provider.{ProviderType, UserService, SocialUser, UserId}

class SecureService extends UserService.Service {
  val activations = new HashMap[String, SocialUser] with SynchronizedMap[String, SocialUser]

  def find(userId: UserId): SocialUser = {
    val user = Athlete.find("email={email}").on("email" -> userId.id).first()

    user match {
      case Some(user) => {
        val socialUser = new SocialUser
        socialUser.id = userId
        socialUser.displayName = user.firstName
        socialUser.email = user.email
        socialUser.isEmailVerified = true
        socialUser.password = user.password
        socialUser
      }
      case None => {
        if (!userId.provider.eq(ProviderType.userpass)) {
          var socialUser = new SocialUser
          socialUser.id = userId
          socialUser
        } else {
          null
        }
      }
    }
  }

  def save(user: SocialUser) {
    if (find(user.id) == null) {
      val firstName = user.displayName
      val lastName = user.displayName
      Athlete.create(Athlete(NotAssigned, user.email, user.password, firstName, lastName))
    }
  }

  def createActivation(user: SocialUser): String = {
    val uuid: String = Codec.UUID()
    activations.put(uuid, user)
    uuid
  }

  def activate(uuid: String): Boolean = {
    val user: SocialUser = activations.get(uuid).asInstanceOf[SocialUser]
    var result = false

    if (user != null) {
      user.isEmailVerified = true
      save(user)
      activations.remove(uuid)
      result = true
    }

    result
  }

  def deletePendingActivations() {
    activations.clear()
  }
}

Jorge was a great help in getting my authentication needs met and he even wrote a BasicAuth.scala trait to implement Basic Authentication on my JSON services.

package controllers

import _root_.securesocial.provider.{UserService, ProviderType, UserId}
import play._
import play.mvc._
import play.libs.Crypto

import controllers.securesocial.SecureSocial

/*
 * @author Jorge Aliss <[email protected]> of Secure Social fame.
 */
trait BasicAuth {
  self: Controller =>

  @Before def checkAccess = {
    if (currentUser != null) {
      // this allows SecureSocial.getCurrentUser() to work.
      renderArgs.put("user", currentUser)
      Continue
    }

    val realm =
      Play.configuration.getProperty("securesocial.basicAuth.realm", "Unauthorized")

    if (request.user == null || request.password == null) {
      Unauthorized(realm)
    } else {
      val userId = new UserId
      userId.id = request.user
      userId.provider = ProviderType.userpass
      val user = UserService.find(userId)

      if (user == null ||
        !Crypto.passwordHash(request.password).equals(user.password)) {
        Unauthorized(realm)
      } else {
        // this allows SecureSocial.getCurrentUser() to work.
        renderArgs.put("user", user)
        Continue
      }
    }
  }

  def currentUser = {
    SecureSocial.getCurrentUser()
  }
}

Summary
My latest pass at developing with Scala and leveraging Play to build my app was a lot of fun. While there were issues with class reloading every-so-often and Scala versions with Scalate, I was able to add the features I wanted. I wasn't able to upgrade to Play 2.0, but I didn't try that hard and figured it's best to wait until its upgrade guide has been published.

I'm excited to describe my latest experience to the developers at Jfokus this week. In addition, the conference has talks on Play 2.0, CoffeeScript, HTML5, Scala and Scalate. I hope to attend many of these and learn some new tricks to improve my skills and my app.

Update: The Delving developers have written an article on Migration to Play 2. While it doesn't provide specific details on what they needed to change, it does have good information on how long it took and things to watch for.

My What's New in Spring 3.1 Presentation

My first business trip of the year was to Dublin, CA this past week. Trish joined me because she wanted to take some pictures of San Francisco. She got some awesome shots as you can see below.

On Tuesday night, I attended Twitter's Open Source Summit with a co-worker and had a great time.

On Wednesday, I talked about What's New in Spring 3.1 at the Silicon Valley Spring User Group. I discussed the support for Java 7, Servlet 3, Hibernate 4 (and JPA 2 with Spring Data) and the new Cache Abstraction. I mentioned how spring-data-jpa-examples is a great sample project and showed a bunch of code from my Spring Kickstart project. I was surprised to find that no one in the audience (all Spring users) was using Java Config. Below are the slides from my presentation and you can also download the PDF.

Twitter's Open Source Summit: Bootstrap 2.0 Edition

Every few months, Twitter hosts an Open Source Summit to talk about tools they're using. Since I happened to be near San Fransisco, I happily attended their latest #ossummit to learn about Bootstrap 2.0. Below are my notes from last night's event.

95% of Twitter's infrastructure is powered by open source. They hope to contributing back to open source by doing 2-3 summits per year. Without open source, there would be no Twitter. You can find a bunch of Twitter's open source contributions at twitter.github.com. They're also big fans of Apache and commit to a wide variety of projects there.

Bootstrap
Bootstrap is developed by two main guys: @mdo and @fat. Mark (@mdo) has been a designer at Twitter for 2 years. He started on the Revenue Team with ads, but has been working on redesign for last 4 months. Has been doing HTML and CSS for about 11 years. He used Notepad on Windows to build his GeoCities site.

boot·strap: simple and flexible HTML, CSS, and JavaScript for popular user interface components and interactions.

Work on Bootstrap started about a 1.5 years ago. Internal tools didn't get the proper attention they needed. They figured out there was a lot of people that wanted good looking UIs and interactions. It became Twitter Blueprint and was mostly used internally. Jacob (@fat) started shortly after first release and decided to add some JavaScript on top of it. The JavaScript for Bootstrap was originally the "Twitter Internal Toolkit" or "TIT" and was built on Moo Tools. Jacob was like "we gotta open source this, it's gonna be huge!" (he was right).

The 1.0 release supported Chrome, Safari and Firefox (everyone at Twitter was on Macs). 1.3 added cross-browser support and JavaScript plugins.

Now there's Bootstrap 2 (just released!). They rewrote all the documentation and components and removed legacy code.

So, what's new? The biggest thing is the docs. Previously had live examples, now shows live examples and why you would do something, as well as additional options. The "topbar" has been renamed to "navbar", but it's still got all the hotness. It's responsive with CSS media queries for small devices, tablets, small desktops and large desktops. This means the layout breaks at certain points and stacks elements to fit on smaller screens.

CSS: smarter defaults, better classes. In 1.4, all forms were stacked. Now they can flow horizontally. Tables are now namespaced so Bootstrap's styles don't apply to all tables. The available table, form and navigation classes are as follows:

// Tables
.table { ... }
.table-striped { ... }
.table-bordered { ... }
.table-condensed { ... }

// Forms
.form-inline { ... }
.form-search { ... }
.form-horizontal { ... }

// Nav
.nav { ... }
.nav-tabs { ... }
.nav-pills { ... }

The goals with 2.0 are consistency, simplification and future-proofing styles. With 1.4, buttons used "btn primary" and it caused problems if you wanted to have a "primary" class in your project. With 2.0, buttons and all elements are namespaced to avoid collisions (now it's .btn-primary).

After Mark finished talking about the design of Bootstrap, Jacob (@fat) started talking about Bootstrap's JavaScript. Jacob works on The Platform Team at Twitter and claims he made a lot of mistakes with 1.x. However, thanks to semantic versioning, 2.0 is a new version and he got to start over!

The biggest change in 2.0 is the use of data attributes (a.k.a. data-*). They were using them in 1.x, but not to the full potential of what they can be and should be. The first class API for Bootstrap JavaScript is data attributes (or HTML), not JavaScript.

With 1.x, you could add an anchor to close modals and alerts.

// 1.x closing modal/alerts
<a class="close" href="#">×</a>

However, if you put your alerts in your modals, you close them all when you likely only wanted to close one. 2.0 uses a "data-dismiss" attribute.

<a class="close" data-dismiss="model">×</a>

This allows you to target what you want closed (modals or alerts, etc.). You know exactly what's going to happen just by reading the code. Another example is the "href" attribute of an anchor. Rather than using "href", you can now use "data-target".

// 1.x href = target
<a href="#myModal" data-toggle="modal">Launch</a>

// 2.x data-target = target
<a data-target=".fat" data-toggle="modal">Launch</a>

If you'd rather turn off the data attribute API, or just part of it, you can do so by using the following:

// Turn off all data-api
$('body').off('.data-api')

// Turn off alert data-api
$('body).off('.alert.data-api')

2.0's JavaScript API has the same stuff, but better. You can turn off the data-api and do everything with JavaScript. They copied jQuery UI in a lot of ways (defaults, constructors, etc.). Bootstrap's JavaScript has 12 plugins. New ones include collapse, carousel and typeahead.

Customize - a new tab that lets you customize and download Bootstrap. It's basically an alternative to customizing .less files and allows you to choose components, select jQuery plugins, customize variables (colors, font-sizes, backgrounds) and download.

What does the future hold? Internationalization, improving responsiveness, more new features and bug fixes.

After both Mark and Jacob gave their talks, they talked together about Community and how great it's been. Even if you're not into writing CSS and JavaScript, they mentioned they still wanted to hear from you. To give an example of great community contributions, one guy opened 50 issues in the last 2 days.

Someone in the audience asked why they used LESS over SASS. Jacob said the main reason they use LESS is because they're good friends with the guy who invented it (Alexis). SASS turns CSS into a programming language, but they wanted to maintain the approachability of CSS, which LESS does. There's no plans to do an official SASS port, but there is talk of doing one. One advantage of the current LESS compiler is they rewrote it to have better output so it's far more readable.

NASA
After Mark and Jacob finished, there was a 5 minute break to grab beers and snacks. Then Sean Herron (@seanherron) (a.k.a. "NASA Bro") talked about Bootstrap at NASA. He actually didn't talk about Bootstrap much, except that they used it for code.NASA. He talked about NASA and how it's playing a key role in the movement towards open data, open source and open standards in our federal government. He mentioned how data.NASA was launched last August and that they helped develop OpenStack. Finally, he mentioned open.NASA, which is a collaborative approach to open, direct and transparent communication about our space program.

Hogan.js
Next up, Rob Sayre (@sayrer) talked about Hogan.js. Rob has been at Twitter for a few months, before that he wrote JavaScript at other places. Hogan.js is a compiler for Mustache templates.

Why Mustache? Because it's similar to HTML and easy to edit. You can mock data as JSON files and programmers are not required.

At Twitter, designers can do the CSS and Mustache without connecting to the backend. It has cross-language support in Ruby, Java and JavaScript. However, client-side template compilation has performance problems, especially in IE7 on a Windows XP box with 4 viruses.

So they had a few choices: work on mustache.js, or use Dust.js or Handlebars.js. The compilers are very nice for Dust.js and Handlebars.js, but they're huge. Handlebar's parser is 4000 lines. The entire Hogan.js file is 500 lines. They decided they were too large to send to the browser's of their users, so they chose to write a better compiler for Mustache.

Hogan.js's main features:

• Compile on the server
• Parser API
• Performance

Performance is much better with Hogan.js than Mustache.js. On IE7 - Hogan is 5x faster than Mustache. On an iPhone, it's about the same (and an iPhone's browser is faster than IE7 on a decent computer). With modern browsers (Chrome 17, Safari 5 and Firefox 10), it's more than 10x faster.

Hogan.js is currently used at Twitter for Tweet embedding, the Bootstrap build process and soon, Twitter.com.

It's been awhile since I got excited about an open source project. Bootstrap has helped me a lot recently, in my Play More! mobile app, on some client projects and I'm in the process of refreshing AppFuse's UI to use it. I love how you can add a class or two to an element and all of a sudden they pop with good looks. The main problem with Bootstrap at this point is that a lot of Bootstrapped apps look the same. There's talk of adding themes in a future release to help alleviate this problem. In the meantime, there's a lot to get excited about with 2.0.

Thanks to Twitter for hosting this event and kudos to Mark and Jacob (and the community!) for such a fantastic project.