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I have been coding in Javascript in the last 2 years of my full time job, using the most recent ECMAScript standard, which has all the cool features. One of them, is to be able to define constants. Other programming languages already had this feature. In Javascript this was not possible to do until ES6 came out and introduced the const keyword.

Sometimes, while I am talking to other developers, I can see some confusion around constants. Some people think that constants are more than they really are. I decided to write this post to make it clear what really…

A home that can be controlled remotely by smartphone…

Since the first time a touched a computer I got eager to learn more and more about it. Nowadays I am a grown up and I am a professional software developer. Technology is just my passion. This means, I usually read articles and watch videos about the most recent tech, the latest computers, smartphones and since a couple of months ago, smart home technology.

More than two years ago, I bought a cheap apartment. It felt like a really good deal and a lot of work at the same time. Not only filling the house with furniture but also, painting…

Javascript is a programming language that can be tricky for beginners. Once you understand how it works, it becomes clear, but in the beginning, you end up debugging problems that you created yourself because you didn’t know something about the language.
We all have been there.
Maybe you are learning Javascript and you are in this process of dealing with problems you don’t see happening in most programming languages.

In this post, I will show you some code snippets and for some, a link to codepen. However, you will see document.write calls instead of console.log. This is just to allow…

As a developer, I spend a lot of time on fixing bugs. If you are a software developer, you can relate to this, right? I love to create new things and develop new features. However, there are a lot of days that most of my time is spent around debugging. Some days are really hard and you have to act like a detective to fix a bug. Those are your detective days. I think most developers have such days from time to time.

The code detective

In this post, I will introduce a bug case and I will explain the process of fixing…

Unboxing Redux

Redux is just flux with only one store

Redux is a Javascript library that helps developers manage the application state, for instance, it can be the logged in user or the followers of a given user in a social network app.

I am working with Redux for a couple of months and it’s being awesome! Something just popped into my mind when I started using it. Then, I remembered that I have read about the Flux design pattern a long time ago. Don’t worry if you don’t know anything about redux or flux, I will try to make it clear…

Embracing let and const and drop out var

If you used to code in Javascript in the old days, you used the var keyword a lot. There was no other way to declare a variable. It was really simple. The only thing you needed to do was just something like this:

var x = 3; var y = 'hello'; // etc...

Since ES6, there are two new keywords, const and let. The first one is a bit self-explanatory, it allows you to define a constant. If you do:

const x = 2;

You can’t reassign another value to the constant x. There are many programming languages that allow…

A long time ago I used Sublime text editor to write my code. However, that “Buy this” dialog was just annoying.

Buy sublime text dialog

I am not saying that the editor is not good enough for someone to buy it but seriously… Do you know someone that actually clicked the “Purchase” button?

Github released Atom, which is free but the performance was not that great (at least, from my point of view, I didn’t do any benchmarks).

Because there were not enough text editors (not really), Microsoft released Visual Studio Code. …

Javascript is becoming more and more a really cool language. Why? Because of all the features introduced in ES6 (ECMAScript 6 aka ECMAScript 2015) and all the other more advanced versions. ECMAScript is just the standardized specification of Javascript. Some browsers already support it. However, it is usually not safe to rely on that, because there is no guarantee that any browser will support the complete specification. The best thing to do is to use a transpiler, that converts your ES6 code to ES5, which for sure will run in any browser.

The command line is a tool used by software developers, to run framework or development tools related commands, run scripts to automate processes and a lot more. If you are learning to code or already code, I think you should not be afraid of the command line. It can seem intimidating at first, but it will improve your workflow.

I met some people that always ran away from anything that didn’t have a GUI (Graphical User Interface). In some cases, you will be just fine. For instance, if you are a C# developer, you will use Visual Studio. Actions related…


I started coding in Java early in college. Even after college, I wrote a lot of code in Java at work due to projects with Java backends or Android apps. I made some mistakes because I was not aware of some features or just because I didn’t have much experience. Along the way, I learned a lot and improved my coding skills. Based on my experience, I compiled a list of mistakes that I have done or I saw others do.

Let’s get into it…

1- Instatiating an Array List without specifying the capacity

When you need to use a list, most times you just create an instance of…

Samuel Coelho

Software engineer, blogger, spreading the word about coding

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