Bitcoin (and many more) cryptocurrency prices have been sky rocketing for the lasts weeks/months, and thus their usage and mining. But have we stop thinking how this impacts the Climate Change? Before jumping into graphs, a quick recap on how cryptocurrencies work: when you buy or sell Bitcoins (for example), your transaction is being recorded into a distributed ledger. This distributed ledger is cryptographically secured against tampering, meaning that once anything is written into it, there is no way of changing nor removing it.

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If you are a AWS SES user (AWS' email system) you probably know that working with its JSON based templates is not a user-friendly task: Text and HTML content are defined as properties of a JSON object It’s a JSON file, meaning that you have to escape some characters, like " in the HTML It’s quite hard to find the content to change in the HTML being stored in a single line But still, is a quite convenient system, as hosting your own email server is quite an effort, and you want it to be reliable.

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What is a Monorepo

Definition: A monorepo is a standard Version Control System, or VCS (such as Git, Subversion or CVS) repository, which instead of containing just one application or unit of software (applications, libraries, micro services, modules…), contains all the components that a project (or company) needs to operate. At first glance, it sounds counterintuitive to host more than one unit of software in a single repository, but there are few advantages on having all components stored in the same place:

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JCrete 2019

Amazing. That’s the one word summary for this unconference. It wasn’t my first time in an unconference, although the previous ones were slightly smaller and my experience then wasn’t that satisfactory as the one I’ve had in JCrete. And I have just discovered the key ingredient for a successful unconference: the people. Because is not only about the technical content of the sessions (which was quite high, don’t get me wrong), but about those interactions during and after the sessions, happening without any planification, as natural as a conversation can be.

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It’s been a while (well, years) since I rotated my GPG keys, and to be honest, now that I know better how to handle a GPG key pair in order to avoid master key rotation, I think it’s the time to get a new pair. This tutorial will show you the steps I followed with explanations on what we are achieving in every step. Environment This is the GnuPG version used in this tutorial (if you are using a different version, probably not every command would work the same, but I wouldn’t expect for the concept to change that much):

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In the previous post we explained from a theoretical point of view how a block chain works. In this post we will get down to work and will implement a working blockchain in Go. If you haven’t read it yet, we recommend you to do it now before continuing. It’ll provide you the basic concepts needed to understand the examples below. (You can find the complete example in this Github repository: https://github.

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Blockchain is one of those buzzwords everyone is listening nowadays, but what it really is? In this series of posts we will dig one general concepts about BlockChain and a little bit of its relation with BitCoin, as well as we will develop a simple blockchain in Go. To put it simple, and as its name states, it’s just a chain of blocks. The interesting detail is that is a cryptographic chain providing some characteristics that make them really useful:

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There has been a lot of noise around Monero and Coinhive lately, or web mining in general, and don’t quite agree with most of what I’m hearing. It all started with The Pirate Bay adding a web mining script to their site, so whenever you’d visit them, your CPU would be used to mine some Monero for them. That was made without any notice to the user, just “stealing” their power.

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In this tutorial I’ll show how to piece together the required NPM modules to build a REST API in Node.js with proper Swagger documentation. We’re going to use Express as the HTTP framework, and the Swagger documentation will be written as inline comments within the code, as close as possible to the handling endpoint or models that will implement the contract, so it will be harder for them to eventually diverge.

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Recently I took the decision of leaving my long beloved distro – Ubuntu (sorry, link in spanish) and moving forward into Arch Linux. And why? As JFK said when the USA was aiming to land on the moon, “not because it’s easy, but because it’s hard”, maybe not that much compared to getting to the moon, but definitely more tedious than Ubuntu. One thing you can take for sure if you take the chance to install Arch: no matter if you success or give up with it, you will learn something new about how a Linux distro works.

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Daniel Pecos Martínez

Passionate fullstack developer. JVM languages, Node.js, Golang & frontend. Blogger, father and active technology local group member.

Fullstack Developer

Amsterdam