I have been reading quite a lot about  Vert.x  recently and finally the day before yesterday I sat down and spent some time exploring it by writing some code. Today I would like to present the outcome. A little bit of history Like all Reactive frameworks/tool-kits/libraries, Vert.x is inspired by Node.js. Back when it was released, Node.js shocked many Java developers who looked down on Javascript, on top of owning the Web client side, JS wanted to conquer also the server side! And thanks to its non-blocking nature, Node.js performed better than typical Java application servers such as Tomcat or Glassfish. Then the Java world reacted (pun intended) and today Vert.x is one of the most matured reactive technologies for the JVM. First Vert.x application  When trying to build my first super-simple reactive  (not really) application using Vert.x, I started following  this tutorial  from the lead developers of Vert.x. That's great stuff, but I found it a little overwhelming

In the previous post  I explained the idea behind the Social Ledger  blockchain network, a fork from Ethereum which uses a new consensus algorithm called  Proof of Social Network Identity ( PoSNI ). Ok, even if that does not make much sense to you, what it means is that you can mine (create) the crypto currency used by this new blockchain network (a clone of Ether cryptocurrency) just using a regular (so far just tested on Linux) computer and a Twitter account. I must tell you that this new cryptocurrency is currently worth zero, but Bitcoin was also worth nothing when it was launched back in 2009, so why not give a try to this since it basically requires just a little of your time? Also, I believe it would be better if your main motivation was not to make a profit out of this, but to help researching in new solutions which could improve the whole blockchain ecosystem. So here are the instructions, first the requisites: - A Linux PC/laptop with connection to the internet and a

One of the main criticisms to blockchain technology is based on the huge consumption of electricity required by the biggest networks (e.g., Bitcoin and Ethereum). That huge electric power consumption  comes from using Proof of Work (PoW) algorithms to prevent " double spending " which is closely related to the " 51% attack ". Some other types of algorithm have been developed as an alternative to PoW, the more popular one being Proof of Stake (PoS), which basically implies that individuals with higher stake (i.e., more crypto money) have more power (i.e., are more trusted) than the rest. Hence, PoS, creates an entry barrier for those who want to become members of the blockchain network, since one needs to own a stake in order to join the network. The key to prevent " double spending / 51% attacks"  is to use something  in the block validation mechanism which is complicated or expensive enough for some malicious actor to replicate or to clone or