Here is where it all begins for me as an engineer. Introduction Since I was a kid I had this feeling of creating new things. It could be anything. But I had to create. I remember that my and I were always drawing some cards on paper and we created a new card game like Yugioh or Pokemon. I wanted my own card game, with my own rules and my own characters.

Here is how we created a successful startup. Doors were about to be opened We had a dummy app, an idea, and determination. That was everything we needed to put our idea on paper and move forward. First, we needed to know how to connect mobile phones to doors, which seemed hard for us at the time. Some research led me to a weird thing called Arduino, an open-source electronics platform that allows us to interact with the physical world, read inputs like light sensors, and provide an output, like blinking a LED or send a message through the internet.

Here is how we failed another access control. And also how we destroyed a successful startup. What to do and what not to do The project was great. Another ambitious one. The bank already had an access control system. More than 4000 branches around the entire country. The main goal was simpler. We needed to build a web application that would interact with the doors of the branches. Easy, we had a private network, from one of the biggest banks in the country, it would never be slow like MonKey was.

Large Classes Usually we start coding small classes. While the codebase evolve, classes get bigger. And bigger. And bigger… They get bloated. We can do the following to refactor large classes. Extract Class We can separate a large class into multiple smaller classes. 1 2 3 4 5 6 7 8 9 class Person { private name private areaCode private officeNumber function getTelephoneNumber() { // Get the phone number } } We can extract data from Person into another class.

Long Methods Those are methods that contains a significant amount of code. There’s no rule for this smell, how long? 10, 20, 30 lines? Each case must be analyzed in its context. It’s important that the method follows the Single Responsibility Principal, here’s a great video from Uncle Bob Martin about Solid Principles which covers SRP. If we want to reduce the length of a method body Extract Method Suppose we have this code:

Introduction Code Smells Code smells indicate that the code needs to be refactored. This means that, while refactoring code, we need to find and get rid of code smells. This will allow more speed and quality in the development. Code will become hard to maintain and dirty, and features will require more time to implement. The team will feel that it would be better to start the project from scratch instead of evolving the current project.