This is not mine, it’s Google’s.

I’ve completed course n° 3 so far and this is my take on them.

I had been interested in user design for a while and when Google announced their fresh certificate courses I thought it was a great opportunity.

Now I think it’s fair to warn you that my purpose is not getting a UX design job with this course. I’m a front-end developer looking to learn and broaden my horizons. But that being said, I really like it!

The Certificate consists of 7 courses which according to Coursera should be completed in six months. I found the timelines Coursera…


Hola! 👋 Alguna vez tuvieron esta advertencia de React, esa a la que realmente le gusta usar la palabra Controlled? 👇

A component is changing an uncontrolled input of type text to be controlled. Input elements should not switch from uncontrolled to controlled (or vice versa). Decide between using a controlled or uncontrolled input element for the lifetime of the component.

No es mío. Lo tomé prestado de: weknowmemes.com

Ya sea si se preguntaron de que se trataba, o si directamente (como hice yo) googlearon una solución y se deshicieron de la misma lo más rápido posible, hoy me gustaría darles un poco de contexto, respecto de lo…


Hi! 👋 Have you ever gotten that Warning while developing forms in React that REALLY likes to use the word Controlled? 👇

A component is changing an uncontrolled input of type text to be controlled. Input elements should not switch from uncontrolled to controlled (or vice versa). Decide between using a controlled or uncontrolled input element for the lifetime of the component.

Not mine. Borrowed from weknowmemes.com

Whether you were asking yourself what that was about, or (like me) googled the solution and got rid of it as fast as you could, today I’d like to give you a bit of context as to what…


If you are working with React, chances are at some point you attempted to render a list of data. And when you did, I’m sure React warned you that: each child on a list must have a unique “key” property. So what now?

As the React documentation points out: “Keys help React identify which items have changed, are added, or are removed. Keys should be given to the elements inside the array, to give the elements a stable identity

So we know that it’s a default property React will expect to find on the element. Often you will be…


Recently I’ve deployed my first app in Heroku. My app ran locally with no problems, and deployment on Heroku was successful, but when I tried to actually open the app I got an “Application Error” with no info on the logs other than it was H10.

Now H10 type errors can be caused by a variety of things. In this article, I will walk you through some of the steps I took in order to find what was the cause of the error in my app.

These are some items to check before you deploy:

  1. Create a Procfile. You can…


I’ve decided to start blogging about my journey to become a web developer, which so far it’s been exciting and fun but also demoralizing at times. I’m not going to lie, I thought about giving up at some point. But the developer's community is just so rich and full of people willing to help and give advice that I always found ways to keep motivated.

As you all know there is a point as you are learning to code, where you feel you are ready to start applying for jobs. And the nº1 advice is always: You need a portfolio…

Pato Montecchiarini

I’m a web & mobile developer. Love all CSS related things. Coding in JS and Dart.

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