Miguel Cabrera

Muerte en Hawaii - Cover Vallenato

2011-09-25T00:00:00-05:00

De esto ya ha pasado algún tiempo, pero creí necesario escribir sobre lo mismo para que quede en la posteridad.

Todo comenzó cuando navegando en internet vi que existia un concurso del periodico ADN para concoer personalmente a los chicos de Calle 13. El concurso consistía en hacer algunas cosas relacionadas con Calle 13, entre ellas hacerce el look de Residente o Cantar la canción Muerte en Hawaii de la misma banda y subir el video a YouTube. El premio se lo ganaba la persona que más likes consiguiera en Facebook.

Dado que me puedo considerar fan de la banda y que he estado neciando con música ultimamente (hice un remix de esa canción con mis juguetes musicales, ver el video abajo) y después de conversarlo con mi novia, decidimos hacer una versión de Muerte en Hawaii de Calle 13 propia para participar en el concurso. Nuestra versión iba a tener unos arreglos propios de la múscia de la costa norte de Colombia (Vallenato y Cumbia para ser más específicos). Como queriamos hacerlo rápido, decidimos hacerlo en dos sesiones por la noche y así subirlo lo más rápido posible para iniciar a conseguir "likes".

Iniciamos grabando los acordes básicos, con suerte descubrimos que la canción estaba en el tono que estaba afinado mi acordeón (Bb-Eb-Ab), asi que no tendria que buscar otro (o comprarme un Roland FR-18 ). Grabamos también los acordens en piano (usando my Korg padKontrol). Con esa base procedimos a reemplazar una de las guitarras con el acordeón, el cual grabamos con mi FastTrack pro y el micro Samsom C03 conectado a esa tarjeta. Todo lo grabamos usando GarageBand que venia con mi Mac. Aprovechamos y grabamos también la caja y la guacharaca del mismo modo. Todo eso en algo más de 3 horas un domingo por la noche.

Aunque sonaba bien, nos faltaba otra guitarra (y el bajo) y era dificil tocarla como queriamos usando algún controlador MIDI, así que le dije a mi amigo Esteban Salazar para que se trajera su guitarra al dia siguiente y así grabaramos la segunda guitarra y los bajos. Conectamos la guitarra directamente a la FastTrack Pro y usando los amplificadores virtuales del GarageBand obtuvimos los sonidos que queriamos tanto para el bajo como para la guitarra. Esteban tuvo algunos problemas identificando algunos acordes que posiblemente con algo de tiempo los hubieramos conseguido, pero como estabamos al trote, decidimos hacer algunas ediciones en Garageband y seguir.

Las voz principal la grabé y con mucha ayuda de mi novia que es profesora de canto. Ella me corrigió algunos problemas de afinación. Los coros los hicimos todos y algunas voces auxiliares las realizó ella.

El "Video" que hicimos esa misma noche y usamos la camara de mi MBP fija, sin ninguna iluminación apropiada y con la ropa del trabajo (y algunos trapos encima). Una vez grabado, hice la edición rápida en iMovie y lo publiqué (recuerdo haberme acostado esa noche como a las 2:00 AM)..

Al final no ganamos (realmente quedamos en muy mala posición en el top :P), pero fue muy divertido hacerlo y jugar con los juguetes (hablaré de los mismos en otro post). El resultado obviamente dista de ser pro (nunca habia grabado algo en mi vida) pero quedé muy contento con el mismo. Depronto me gustaría hacer algo con un acordeón más elaborado (hacerlo más vallenato tal vez) y tener cajeros y guacharaqueros de verdad para que quedara bien grabado. (por que me tocó grabar todo eso a mi, la calidad no es la mejor).

Abajo el vid con el resultado final. (El cual es totalmente Cheezy, pero divertido). Por favor obviar los errores de sincronización del cantane y la música :D.

Bonus Track

Aca un remix de la canción Muerte en Hawaii de Calle 13 con una percusión (realizada con Garageband y mi Korg padKontrol):

AmazonXCH - Mira los precios de Amazon en tu Moneda Local

2011-06-13T00:00:00-05:00

Cuando yo tengo un viaje a estados unidos o algún amigo viaja para allá, mucho de nosotros aprovechamos y compramos cosas. Uno de los sitios favoritos para comprar en USA tanto mio como de mis compañeros de trabajo es Amazon. Los precios, como es de esperar, están en dolares, por tanto tenemos dos opciones para ver los precios en nuestra moneda local: 1. Hacemos el calculo aproximado (por ejemplo 1 dolar = 2000 pesos) o 2. usamos una sencilla calculadora y juiciosamente realizamos el calculo. También, si usamos algún buen navegador podremos usar alguna extensión que nos ayude con ese calculo.

Sin embargo, lo ideal sería poder ver precios de nuestra moneda local directamente en Amazon. Dado que no vi ninguna extensión que hiciese eso (y la verdad no busqué de a mucho) y que también que tenia ganas de aprender Javascript (por eso del HTML5) decidí hacerme una extensión para Google Chrome (el navegador que uso) que hiciese precisamente eso, mostrar los precios en la moneda local. (En mi caso COP).

Se llama Amazon-XCH y la la desarrollé basandome en la extensión Currency Converter para Chrome, es decir, usa como fuente de datos Yahoo Finance, por tanto usa los datos en tiempo real del mercado internacional no la TRM (tasa oficial) del día, sin embargo es un buen aproximado, además de permitirle a la extensión mostrar los precios en cualquier moneda del mundo :-). El precio aparece entre parentesis luego del precio original en dolares (depronto cambio esto en el futuro cercano).

Dado que es la primer aproximación el código no es de lo mejor, adicionalmente hay algunos inconvenientes en los que trabajaré si el tiempo me lo permite:

Cuando el precio hay que verlo en el carrito ("see price in cart") para que se muestre el precio hay que darle click al link, cerrar el frame y darle click otra vez.
Los precio desaparece cuando un producto tiene varias opciones de configuración (como el Kindle 3G).

Pueden descargar la extensión desde la Google Chrome WebStore.

El código fuente (licenciado como MIT) pueden verlo en Github.

Creo que debería hacer un post similar a este en inglés pero es algo tarde y tengo sueño.

Buena noche.

Operations vs Development

2011-02-14T00:00:00-05:00

Since I graduate from college (actually a little bit before that) I always felt like I was in between worlds. I had a lot of friends from the university that had very defined profiles and skill sets. Generally, they were either Developers (some of them very good coders) or they were oriented towards networking and systems administration (many of them literally hated programming).¹

Nowadays, I still feel like a hybrid between the Sysadmin and Software Developer. Even though now I am "Software Architect" in a software development department, I really do a lot of stuff that is related to the operations part. As my team generally defines the best practices and the technology to use company-wise, It is crucial for us to be well versed in sysadmin tasks.

As I mentioned above, my team has to define/develop many of the technologies that the other development teams use, that includes SCM procedures tools, integration technologies, application servers, shared libraries, development environments, common functionality libraries and so on. As you see, many of these activities require a lot of interaction with operations people. So, we generally end up working, or at least talking, with the operations crew much more frequently that the common Software Developer. Sometimes, we even have to perform "operation's" activities on our development environment first, and then send a "How-to" manual to the operation people to perform.

As is common in many enterprises, Operations is clearly separated from Development and from QA. Moreover, QA is also split in two different teams: the "Technical QA" which "belongs" to Operations and the "Functional QA" which belongs to Software Development department ². So, my company is no different from a common enterprise, both areas have different agendas and they both claim to be "aligned" with the "strategic objectives" of the business. However, when it comes to get a new application to production (which includes getting the hardware, testing, preparing the environments, and other related task) or simply releasing a new version of an already existing application into production, all the process (even in our development department) are either manual, duplicated or extremely tedious. And generally a combination of all of them.

Currently, we are in the process of improving our Software Development Methodology. I am in charge of the SCM process definition, but only for the dev team. But this is no easy task, given the broad scope of the process and that we are basically in diapers when referring to CM. Some could think that this is a great opportunity for us to automate and improve these process, including Release Management and Build Engineering (namely, continuous integration, unit testing and other industry best practices). However, although we certainly would do better if we apply this to our processes, at the end, we would hit operations' "wall" nevertheless.

In the beginning I believed operations was a bottle-neck because they were just not agile as they should, or not as good as they should. But there was another factor I did not take into account. Operations inherently wants to prevent change, given that they are the responsible for the stability of the system and they are also rewarded for that. If you make changes (e.g deploys, new applications, etc) possibilities of making the whole system unstable increases. But if you do stop changes (or make the process of releasing new changes extremely cumbersome) the change will be accumulative and big changes are far more dangerous than small ones.³

The "wall of confusion" Source

So, what are the specific problems I think we have when comes to our overall SDLC process:

Information silos. We have different systems to handle requirements from users, task planning, bug database, test results and deployment requirement. That is not necessarily bad, but none of those systems are connected, so each of them have a work-flow and database. Therefore, there is no way to trace back a change with a release to production or to bug (issue).
Cumbersome Processes: The process of getting a new application on-line is cumbersome, filled with a lot formats that ask impossible question to answer.
Manual Build & Release Process: Once the application is "on-line" and we want to release a new version of the software all is done "manually", from the compilation, testing to the configuration of environments. Some of those task are requested using ticketing system, asking for the same information over and over (We have even two different process for asking the same stuff and performing the same task). In other words a Build and Release process should be created.
Manual Environment Management The environment administration is done also manually, and a lot of problems occurs when a change is requested. Finding the origin of the change is difficult if not impossible. Environment configuration should be baselined and handled using appropriate tools. (Like or Chef or Puppet, just to name some Open Source alternatives). That is, the environments should be first class citizens and automated process for managing the changes should be put in place.
Dependency Management is not managed at all by operations, I had to create a Subversion repository with some manual procedures in order to stabilize the system. (See my older post). We have minimized the problem of "It works on my machine". However, there is still problems with configuration files that are not managed at all.
Split QA Teams: The QA department is split in two, technical and "functional", each managed differently and with different tooling and objectives. Many of the test are manual, making them difficult to re-schedule. There is no Code Coverage or Automated Unit Testing, only System testing. This not only makes the QA process slow but also may prevent a proper identification of application issues. I believe also the communication between teams (QA, Ops and Dev) can be improved.

We have more or less a broad view of the problems, and It is evident that if Operations and and Development worked together this could a lot of them could be tackled. Recently, a new "approach" called DevOps have taken strength in the last few years. Wikipedia (and the Original article) defines DevOps as

[…] a set of processes, methods and systems for communication, collaboration and integration between departments for development (applications/software engineering), technology operations and quality assurance (QA).

DevOps Approach vs Traditional Thinking:

Based on the This presentation by John Allspaw (from Flickr) here's the traditional thinking (slightly modified):

Developers job is to create software and add features.
Operations job is keep the site stable and fast.

But the truth is that

Operations job is NOT to keep the site stable and fast.
Operations job is to ENABLE the business
Change is the root of all failures and outages

Basically, what DevOps is saying is that we areas should communicate more, or at least more assertive, tools and methodologies should be used to automate from the build process to release process. Which is an area that "belongs" to the Configuration Management set of processes. In other words, it creates new ways of integration between QA, Operations by Development by creating a culture, a set of process and automation tools, to lower the risk and support change, instead of avoiding it. Right now the definition is still somewhat unclear, however, at the end, what is being proposed is a pattern for managing IT areas.

Let me be clear, I am not arguing that my company should jump into the DevOps approach in order to succeed. However I do believe that DevOps people propose is valuable, those thing need to be taken into consideration urgently in my organization. They are:

Serious Change in the culture in both areas.⁴
Unified processes: The SDLC should be unified and the appropiate metrics should be defined.
Unified Tooling: Tools using in both sides should be the same, including versioning, ticketing system and version control system.
Version controlled Software Library.
Version controlled Environments
Automation of Manual Task, including testing and deployment.
Assertive communication (whatever that means in context).

Some folks in my organization argue that they are just following ITIL to counter my argument a about their responsibilities in some of the task I just mentioned above. Either they forget completely about the ITIL Service Transition process or their interpretation is quite limited to the minimum effort to get it done. In either way, you can implement the process in any way you like. The fact that you follow ITIL by doing some archaic process does not make you better than a organization that does not know what ITIL is, but has a highly automated and optimized processes. I mean, it is just a matter of common sense.

To summarize, I believe that Suramericana should re-think the whole SDLC process, with a strong emphasis in the definition and application of a good Configuration Management process across the areas (including Operations), with specific emphasis in the Build Engineering, Release Management, Environment Management processes and strong emphasis in inter team communication in order to solve the issues I just described.

Footnotes:

¹ There was also the ones who did not think to hard about that, they were more attracted towards the "management" of software development.

² I really believe that QA department should be a completely different area, as it seems to be the best practice.

³ 10 Deploys Per Day - Dev and Ops Cooperation at Flickr by John Allspaw

⁴ I really like the hard way recipe of Ted Dziuba in his DevOps bashing article, which includes putting developers on call rotations, making develop in the same operating system they deploy and that a making sure a downtime never happens again.

Hyperref Options Link

2010-11-10T00:00:00-05:00

If you ever need to know all the options of the Latex package Hyperref (that nifty package that allows you to create nice TOC and Link inside a latex document you may check this link

Now if you want to use hyperref along with Org-Mode you may want to put something like this on top of you .org file.

Sobre Ser Costeño, Colombiano, Latino y Ciudadano del Mundo

2010-11-05T00:00:00-05:00

Por motivos familiares, mi niñez transcurrió entre distintas ciudades de la costa norte colombiana. no fueron muchas, ni los viajes tan constantes, pero
los cambios y/o viajes fueron los suficientemente frecuentes para generar un de alguna manera un desarraigo por costumbres o por ciudades.

Aunque siempre que me preguntan digo que soy Samario, Yo realmente nací en Cartagena de Indias pero solo viví un periodo de tiempo muy corto cuando estaba bebé. En en mi infancia y parte de la adolescencia viaje (y viví) en varias partes de Colombia (incluyendo ciudades y pueblos como Cali, Buga, Sincelejo, Sucre y por supuesto Santa Marta, la ciudad de mi familia materna y el lugar donde pasé la gran mayoría de mis periodos vacacionales). Casi todo ese tiempo, estuve en ciudades y pueblos de la costa. Centrandome viajando constantemente entre el departamento de Sucre y Magdalena.

Lo máximo que alcancé a vivir en uno de esos lugares fue 6 años y creo que en promedio no más de 3 y 1/2. Definitivamente lo malo de moverme tanto es que
nunca me sentí que era de un lugar. Sin embargo, vivir en tantas partes de la costa norte me dio una visión más completa de lo que era la costa norte, sus diferencias y similitudes en las distintas regiones que visitaba (que por las cuales estuve de paso).

Cualquier persona pensaría vivir en tantos regiones de la costa atlántica me haría más costeño, pero no, creo que el desarraigo que eso causo, me hizo buscar, durante mi adolescencia, referentes culturares que en ese momento pensé superiores a los locales.

Intenté encontrar una identidad siendo rocker y ensayando distinto tipo de musica y maneras de vestir, iniciando en una combinación extraña de rapero metalero, pasando por gruncheto hasta reggae dancehall guy. Pero al final, despues de explorar mucho, crecer (y madurar algo) creo encontré que a uno no lo define la música que se escucha y la verdad, menos la ropa que viste.

Comencé a descubrir el folklore de mi tierra (de una manera que extraña que ya contaré) y estando lejos de mi tierra (Medellín). La verdad me gusta mucho. También leí muchos libros de historia latinoamericana y colombiana, tratando de entender por que estamos como estamos, por que tal vez somos como somos y que significa ser una mezcla de culturas muchas veces tan distintas.

Creo que logré algo importante, ubicarme dentro del mundo como latino, como colombiano, como costeño. Actuando local con una visión global. Valorando y disfrutando influencias culturales foraneas sin anteponerlas nunca a las expresiones de mi tierra.

Esto tiene sus ventajas, muchos amigos van y disfrutan de Placebo, pero no pueden escuchar un Vallenato o una cumbia. Otro amigos dicen que Metallica o Iron Maiden es musica de locos. Yo puedo ir un concierto de Bomba Estereo, escuchar Andres Landero en mi carro y pasarla muy bien en un concierto de Placebo. Puedo valorar expresiones locales, mientas otras personas las rechazan “Por que sino suena a gringo no sirve”. Puedo sentirme Latino, Colombiano y Costeño, Muy orgulloso de ello, mientras otras personas sueñan con haber nacido en un barrio de Seattle, en una ciudad Alemana o en algun pueblo nordico, con su cuerpo lleno de genes vikingos.

OC4J, Shared Libraries Ruby and Graphviz

2010-06-18T00:00:00-05:00

(all of that, in just one post)

Since July of 2010 I have been working in a insurance company called Suramericana. There, we have a software development department and I work as “Architecture Analyst” whatever that means. Anyway, what I do there is all the non-functional stuff that “supports” the department software (security, messaging, environment, software development methodology, etc.).

Like many enterprises, applications are built using Java (specifically J2EE or JEE) using Oracle Application Server (OC4J) and Oracle Database. Many of these J2EE containers support what is called in java shared libraries. A library is a bunch of jars (therefore a bunch of classes), so this is a way to “elegantly” organize class loaders defining dependencies between them and assigning them to the the required applications. In OC4J, the libraries are defined in a file called server.xml. You can see an example here

When I got to Suramericana, there was no one was in charge for administering the shared libraries, and there was a lot of disorganization in all the enviroments causing delays in the when deploying to the test or production environment. And a lot of people asking for support to the Architecture team (my team), so we basically couldn’t focus on our project because the support load was to high, and the shared libraries dependencies issue was the one of the main reasons.
So I decided to do something about it. I talked to my boss and we decided to organize the whole thing and create a process (some part are manual but that is another story) to organize the shared libraries and put them on a Subversion repository. Now, all containers have the same shared libraries and there is a control when someone wants to modify or add a shared library. We now have almost not support regarding shared libraries use.

Well, while I was doing all this I wanted to have like a graphic representation of the shared libraries and its dependencies. I though that maybe Graphviz could help me doing that. As I needed to parse the XML quickly and I am Ruby fan I chose Ruby to implement it, I discovered a Ruby gem that generates dot files (Graphviz file format) using Ruby as a DSL for it. So I wrote a small script (see the end of the post) that took the xml file, parsed it, and based on the references to other libraries, created a graph. I obtained a cool image like:

As you see above, the name of the shared libraries with the version are the nodes and directed edges represent the dependencies. For example, we see that log4j have no dependencies and pretty much all of the other libraries depend on it.

I really liked doing this in Ruby. Ruby have powerful meta-programming capabilities and a flexible syntax that allows a programmer to create such DSL really easily. I also discovered a small bug and sent a trivial patch to fix it ;-P.

You can see the code below. Remember, I am not a Ruby expert, so comments are welcome :-)

Interesting Articles on Machine Learning

2010-04-17T00:00:00-05:00

I have done a little bit of Machine Learning back in college, I paralellized
a transductive SVM to get improvement over the a really slow algorithm so the topic still interest me. I just discovered a cool article by Google Research about empiric lesson learned while developing a real world machine learning algorithms.

Lessons learned developing a practical large scale machine learning system

Now while reading my feed I discovered this article that introduces a cool machine learning algorith for ranking and matching players for the Xbox live. It also have a good introduction to statistical machine learning. Totally recommended.

Computing Your Skill

Happy reading :-) .

N900 and Installing Maemo SDK on Ubuntu x86_64

2010-03-28T00:00:00-05:00

Well, this is my first post on my new blog. It have been a while since I blogged and I really want to do it again. I think that with this new tool which is simpler and is text based I will be able to get
more easily the thoughts out of my head.

Around mid-February I bought a Nokia N900 (see video below) from a local Ebay-like Web. The N900 is a Linux (Maemo) based “Internet Table” with phone functionality. Others prefer to call it a Linux Smartphone. In any case is a device that gives you the basic functionality of a phone plus the experience of a desktop Internet experience providing you among others things:

Mozilla-based web browsing with full flash support
Common IM platform supported integrated into one (Conversations)
Skype support
Music, Video, and Radio receiver and transmitter.
Mail for exchange with Calendar sync.

And given that it is a Linux-based device, porting applications is somewhat easier, so with minor efforts you can get Gimp, Open Office and a extra bunch of application running smoothly on this device.

The SDK for this device is free of charge and the supported Languages are C,C++ and Python. I would have liked support for Java, Ruby and Mono. I thing the lack of support of Java is one the grey spot of this device.

In general I am happy with the device. It pretty much fulfill all my expectations, however here some things I believe could be improved:

More applications: The lack of commercial application could hurt badly this device.
Battery life: Life duration really suck. I will have to get an extra battery.
More documentation and support for developers.
Support for multiple accounts in mail for exchange.

Installing the SDK on Ubuntu x86_64

I am planning to code some application for this device (while learning some Python) so I decided to install the sdk on my Ubuntu 9.10 box. I ran into problem using the GUI installer that is related to the vdso32 kernel option. In order to install the Maemo 5 SDk you should put “vdso32=0” in your kernel command line. As it is common in Ubuntu, wich each realease a lot of stuff changes so I couldn’t find where to put this option. But doing it could be more easy. Look for the file /etc/default/grub and append “vdso32=0” to the GRUB_CMDLINE_LINUX variable. Mine looks something like this:

# /boot/grub/grub.cfg.
  GRUB_DEFAULT=0
  #GRUB_HIDDEN_TIMEOUT=0
  GRUB_HIDDEN_TIMEOUT_QUIET=true
  GRUB_TIMEOUT=10
  GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
  GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
  GRUB_CMDLINE_LINUX="vdso32=0"
  (...)

After that reboot and the installation is just a matter of clicking “next” :-).