Did I spend a whole week in Trivago learning JavaScript from Kyle Simpson?

It looked like a harmless Pull Request. I saw this contest by Trivago where 3 people would be fortunate enough to win a free spot in a 5-day JavaScript workshop with Kyle Simpson.

Well, I was fortunate enough.

Yeah, that’s about right. 5 days with Kyle Simpson. For free. In Düsseldorf, surrounded by other JavaScript engineers. How cool is that?

The menu for the week was the following:

• JavaScript foundations
• ES6: the good parts
• Rethinking Async
• Functional Light JavaScript
• Functional Light JavaScript II

One topic per day. 8 hours a day.

Did I learn a ton?

Heck yeah I did.

Did my brain hurt every evening?

Heck yeah it did.

I thought I knew JavaScript. It’s not only that I didn’t, is that now I feel that I discovered a ton of things I didn’t know I don’t know. (This sentence was as hard to write as it is to read).

5 days a week

Monday was great because we focused for 8 hours on low-level JS stuff such as scoping, hoisting, closures and so on.

We had time to go over “classical JS interview questions”, and we could spend the required amount of time on each question, to make sure we fully understood what was happening and why.

So, for instance, it’s clear to me now why this two loops don’t output the same result:

for (var i = 0; i < 10; i++) {
  console.log('The number is ' + i)
}

for (var i = 0; i < 10; i++) {
  setTimeout(function() {
    console.log('The number is ' + i)
  }, 0)
}

Do you want the answer, and how to solve it? Ask for it 😜 Or, ehm, well, use Google.

On Tuesday we explored new ES6 functionalities, and instead of exploring the usual suspects (let/const, arrow functions)… we explored object/array destructuring, template literals and other “not-so-famous” ES6 features.

My mind was blown during Wednesday when we focused on asynchronous patterns and how to handle asynchronous data management in JavaScript. I mean, I thought I was well versed in Promises. Oh, how wrong I was.

Finally, we spent the last two days on functional programming. Kyle’s approach is great as we tried to get our heads around FP without dealing with all the convoluted stuff (monads, transducers, and other hard-to-type-and-harder-to-understand words).

I tried to jot down every piece of knowledge I received and also trying to stay focused to understand the concepts and also the nuances behind the language. Besides that, I loved Kyle speeches on “offtopic” issues such as learning mindset, code quality and what it means to be a “senior” developer. He didn’t explicitly mention seniority, but from my point of view, he was describing what a “senior developer” looks like. I loved that speeches, as they provided real value besides JavaScript and any specific programming language.

Kyle asked us to try to go over our notes a week or so after the workshop. I did (even though I was on vacation), and a month later, I’m planning to put everything together and wrap it up nicely on a Github repository so I get to go over my notes again and to make sure I share what I learned with everyone. You know, learn in public.

It was also my first time traveling alone. I was excited about the idea of exploring a whole new city by myself, and it was worth it.

Let me also share Debbie O’Brien’s post about her experience. She was another of the fortunate developers who earned a spot in the workshop. In her post, she goes into detail about the whole week and it really captures what being at Trivago for 5 days felt like. I’m glad I met her! I spent a lot of time with Tomeu and Rasmus as well, who happen to be frontend developers for Trivago but they work in Palma, not in Düsseldorf. I learned tons of things about JS, but I also learned from the people I met during the week.

A meeting room at Trivago. True story.