Early last week I had the chance to attend the Symposium on Blockchain and Distributed Ledger Technology organised by UNSW. I wasn’t aware that UNSW was so heavily involved in the community until this event and have since learned about their interest group which has been going on for a while.
The talks had a healthy mix of research and industry case studies with subjects ranging from the technical challenges of current blockchain implementations to the legal implications of distributed ledger technology.
The panelists took turns in giving their views around blockchain, investments and regulation, leading into a Q&A at the end. I was running late to this session and believe I may have missed Ross’ individual slot.
A bit late for a EuroClojure 2014 post but I suppose “better late than never” applies here.
The best part of every conference is the networking. Meeting new and interesting people is priceless and I did plenty of that - mostly over Polish beer and food. Polish beer isn’t the greatest but if you must have it, better stick to Żywiec. It’s widely available and was the one which didn’t give me a headache :) - I’ve been told there are amazing microbreweries though I didn’t get a chance to try any while in Krákow.
YOW! LambdaJam is a conference targeted at intermediate and advanced functional programmers and is organised in talks, jams and workshops.
Talks are the traditional format and are 30 minutes long;
Workshops aim to introduce a specific subjects to attendees in great detail and are up to two hours long;
Jams are hands-on sessions. Participants will be guided through pre-defined problems around a given subject/technology and encouraged to work through the solutions either by themselves or ideally as small groups. Jams are also 2 hours long;
I was in São Paulo last week - the 3rd and 4th of November - for RubyConf Brazil. For those who don’t know, RubyConf Brazil is the evolution of Rails Summit Latin America, where I had the privilege to speak in 2009.
This year though, all bets were off. Fabio Akita and Locaweb put together a great event, with over 700 attendees and about 30 speakers split in two streams and two awesome days.
I met some really cool people, discussed a whole bunch of technical subjects and managed not to get so nervous in my first presentation ever - I'm not counting internal presentations I've done for my team...
My slides and source files can be found here. Feel free to contact me with questions if you got any.
I'll be speaking at this year's Rails Summit Latin America in Sao Paulo, Brazil. It will be a good opportunity to meet some amazing people and visit friends back home! :)
Overall I'll be spending 12 days in Brazil, with 2 of them dedicated to the conference. The other 10 I'll be in Rio de Janeiro visiting my family and friends. I strongly advise you to spend some time in Rio too, if at all possible. It's an amazing city and you can contact me if you have any questions.
Back to the conference, my session is called JRuby in the enterprise world: Using Rails with legacy code, and will be given in the form of a tutorial. I will walk you through some problems we had while making this kind of integration at my company, focusing mostly on dependency management.
At the end I hope you'll have a good understanding of what JRuby is capable of in a legacy environment.
If you're planning to attend and would like to hear anything specific about JRuby, please let me know, I can try and squeeze in.
As always I expected a good talk from Ola and once more he delivered it. But this one was different. It might have been even boring to some ruby developers since we saw a fair amount of java code in this presentation. Ola gave us a tour through the main classes that make JRuby possible with a single purpose: so we can check out the code and hack ourselves. You can download his slides here.
If you've been following both JRuby and Ola Bini for the past year or so, you've noticed the trend and evolution of this alternative - and so far the most complete one - implementation of the ruby language. Specially at conferences.
Last year at QCon London, Ola was also talking about JRuby. At Euruko '08, in Prague, Charles Nutter also talked about it. RailsConf in Berlin also had its share. What all these talks had in common is that they talked about JRuby from a user/developer point of view. They were selling the solution. Convincing people to use it and presenting successful use cases.
And as the trend goes on, JRuby is now faced as a true alternative - one that we, btw, believe here at the company as we're actively using it - and it seems that now the call is for help. Help to make JRuby an even more complete and overall better ruby implementation. Charles' call for help was a great step. As he states, it's a good way to get your feet wet. I answered the call and am hacking JRuby myself, having already submitted a couple of patches. Perhaps this was the reason for which I enjoyed the talk the most. I was already familiar with some of the structure and classes in JRuby.
There were 2 more talks about JRuby: The Pleasure and Pain of Migrating to jRuby, by Steven Bristol and Integrating Enterprise Java with JRuby and Rails, Michael Johann. Unfortunately only the first one was a real case experience, where Steven walked through the problems he faced integrating JRuby with an existing java project. Interesting insights.
Michael Johann basically presented a short tutorial on how to integrate rails with EJB3 which, albeit interesting, failed to address issues faced on real life projects, like dependency management. Issues which we have already addressed in a very cool way here and I plan to share it soon. Still deciding how though...
I'm back in Madrid again after the RailsConf and I think it's time to say something about it. :)
First off, the infrastructure provided by the conference was really great. The rooms, WiFi connection, food... Really well organized.
Now to the sessions, highlights:
Tutorials (Tuesday) - Meta-programming Ruby for fun and profit (Neal Ford, Patrick Farley) The old and good techniques that made Ruby so powerful. Here Neal and Patrick walked us through the main tricks to meta programming like open classes - and conditionally open them - , dynamically define methods, sending messages to objects and how Ruby can help test your Java code in a much easier way.
I've put the link to the slides but honestly I don't think they're too much useful without the talking.
Sessions (Wednessday) - EC2, MapReduce and Distributed processing (Jonathan Dahl) Jonathan explained the theory behind MapReduce using very simple ruby examples, providing the basics on how to distribute and paralelize tasks accross multiple machines.
He also introduced Hadoop, a platform built in Java that "lets one easily write and run applications that process vast amounts of data". What I liked the most was the simplicity he explained this subject. As of today, his presentation is not available online. Stay tuned as I'm gonna update this post with the links, as soon as they're available.
Sessions (Thursday) - Debugging & Testing the Web Tier (Neal Ford) If you've been concerned about testing your app's web tier lately, this presentation would probably not show you anything new. Neal talks about the need to debug and test javascript behaviour accross multiple browsers, using tools like Firebug, JSUnit and Selenium. If you have no idea about what these tools are, please stop now and go evaluate them!
We are pretty concerned about testing on my actual job, but selenium tests can be a pain sometimes - a.k.a extremely slow. And what ends up happening is that they are forgotten. Developers only run the test suite if it's not painful and it's lightning fast. Here's is where the highlight for this session comes: CrossCheck.
The idea is to be able to test your javascript code accross multiple browsers without the need to launch them. In fact, you don't even need a browser installed. The negative point is that it's kinda fallen behind because now you can only test older versions of browsers. But since the project is getting a lot of traction, I'm pretty sure this will be solved soon.
Conclusion
My overall impression of the other sessions I attended is that some speakers just didn't have time to properly prepare themselves, what made me think this years's RailsConf wasn't all that I expected.
But I also met interesting people and after all one of the key points in a conference is networking. :)
Definitely worth it though. And that's why I took the time to provide this highlights.
And while we're talking about JRuby, it's impressive how it's becoming a recurrent and big subject. Fast. It had its own small space at big event like QCon and in the last Euruko in Prague, we had a presentation by the JRuby Core Developers Charles Nutter and Thomas Enebo.
Big companies are sponsoring JRuby's development indirectly or directly, like Sun. And other big companies are endorsing its production ready state, like Oracle, which has a publicly available website developed with JRuby On Rails.
Almost 300 attendees already registered for the event. And a few very interesting people will be speaking there like Matz and DHH (this one, through skype).
Besides that, the organization staff is scheduling 2 parties, friday and saturday, for the attendees.
Networking comes to mind, doesn't it? I think it will be a great opportunity to meet interesting and bright people.
Today was the first day of the conference and it started with a tutorial about DSL's with Martin Fowler, Neal Ford and Rebecca Parsons. We also had as attendants Ola Bini, core developer of JRuby, and others. My expectations were pretty high and the presentation didn't let me down. I'll try to put here toghether my impressions and some notes I took while I was there.
Marting Fowler started discussing what DSL's are and giving some examples that many of us use in our day to day Job. Like the XML configuration files in the Java world. It is a kind of DSL, it has it's own keywords and syntax in order to express some information that will be used , for instance, to configure an underlying framework.
The problem with XML is that it becomes hard to see the overall behavior behind it. It's not very fluent to understand the purpose of an XML file just by looking at it for the first time. There is too much "noise". Things that get into the way of the readability. - YAML files are an much more readable alternatives to XML.
The same happens with a standard framework api code. Let's take for instance a sample API configuration code written in Java to tackle the domain of hotel reservations. A framework like this could have the following implementation:
HotelService hotelService = new HotelService(); PersonService personService = new HotelService();
Hotel hotel = hotelService.findById(1); Person guest = personService.findById(10) ;
hotelService.book(hotel, reservation); Of course implementations of this simple example may vary but we can see here some of the readability problems. One approach we could use for that is to develop a Fluent Interface to wrap this API. This was one of the techniques explored during the tutorial and the actual fluent interface could now look somewhat similar with this:
new Hotel(1) .book() .forGuests({ person.find(10) }) .rooms(1) .from("2008-03-10") .to("2008-03-10");
Much more readable, huh? One of the main benefits of using DSL's they highlighted in the tutorial is the simplicity of code you can achieve. You can actually show this code to a business person and he can understand it. This is a kind of internal DSL.
But there is still a bit of noise in this code. The the parenthesis which are not always desirable, and the use of double quotes for dates. But, this is Java code, and Java doesn't give too much room for you on the DSL subject. Here was when the speakers changed their focus a bit to Ruby. It's dynamic nature and metaprogramming techniques provides a powerful flexibility that allows for a looser syntax.
So in ruby the previous interface could look like this now:
We got rid of the double quotes and the code looks more fluent, like a normal english sentence. I doubt a business guy woudn't understand what this code is doing. With this, we can get closer to the business guys, with a common vocabulary, and fill the gap between us.
This is just one of the ways we could have written this code and is not the actual example used in the tutorial. The syntax also really depends on how readable you wanna make your code. I'll provide those later when they release the digital format of the presentation.
So one of the flows that the development of an internal DSL can get is to build a framework and define the DSL on top of it. But we should also keep in mind that DSL's shouldn't be general purpose programming languages. They should be created to tackle a specific kind of domain problem, so we would have a whole system made of small DSL's.
Another interesting subject that was touched is testing. How do you test DSL's? The suggested approach, and that I think is quite reasonable, is to have separate tests for the underlying framework and another to test the DSL and its parser you can assure you have the expected behaviour of both parts.
This is really just a summary of my thoughts and of what happened there. I'm not going into too much details right now but if you found something too abstract - and it is! ;) - feel free to ask details. I'll be more than happy to help.
This is definetly an interesting subject and now I'll head to play more with all that. :)
PS; This is not the whole presentation, just the best of it from my stand point. Other subjects include External DSL's which can actually involve you coding Lexers, Parsers and Compilers. It's usually not worth the hassle. And it's too complicated anyway, that's why I left it out from this post.
Next week I'll be at QCon, in London, so if any of you are going to the conference and would like meet up for a couple of beers and a tech talk, please don't hesitate to drop a message.
For those of you who have never heard of QCon before, it is a really nice event to play along with some of the most popular names in the software engineering community. This year's conference features people like Martin Fowler, Neal Ford, Erich Gamma and much more.
So stay tuned, the conference takes place during the whole week and I'll try and keep you posted about what's happening over there.
