Hernan Rajchert

I started following and learning TypeScript since version 1.4, back when the Angular team announced that they were going to use it for the next version of the framework. Once I was comfortable enough I introduced it to my colleagues and migrated a large codebase to it. While doing so, I created multiple open-source libraries including a video player and a Node.js starter kit. Now I don't use Angular that much, but I still use TypeScript for most of my projects. I think that restricting the way we program lead us to more correct code. Here are some of my TypeScript blog-posts: https://medium.com/@hernanrajchert/creating-typings-for-curry-using-ts-3-x-956da2780bbf https://medium.com/@hernanrajchert/typescript-meets-google-sheets-a4be3891af85 https://medium.com/@hernanrajchert/guardians-of-the-code-ec0e3d3bc06a Here are some of my TypeScript talks (in Spanish): TypeScript can do that?: https://www.youtube.com/watch?v=56s94hJBs1Q Whose error is it anyway: https://www.youtube.com/watch?v=WIf582XYm-w ¿Qué es TypeScript? Conoce sus ventajas: https://www.youtube.com/watch?v=W8zpuxuGlqU

I started using Node in 2012. The idea of having the same code running in the front and the back caught my eye. Actually, my first open-source project was a library that helped us use the same router in a Backbone and Express app. In 2016 I created a Node and an Express course in Acamica, an online platform for learning programming in Spanish. More recently, I created a TypeScript Node starter to ease the creation of new projects, and I used it to migrate a PHP monolith at work into several microservices.

I decided to focus my career in web development after I graduated from college in 2010. In the beginning, I worked mostly in the backend with PHP, but in 2012 Node.js caught my eye. I liked the idea of having iso-morphic JavaScript, code that could run both in the front and in the back without too much hassle. I've closely followed the evolution of the language since a time that ES5 wasn't fully supported by all major browsers and before the Promise/A specification was known. I liked the asynchronous nature of the language and learn how to program with Callbacks, Promises, Generators and Observables. I've even created an online course about it. Now I program with TypeScript and PureScript, which are two statically compiled languages that generate JavaScript. I've started a blog series about it called "Not all compilers are created equally" https://blog.logrocket.com/typescript-vs-purescript-not-all-compilers-are-created-equal-c16dadaa7d3e/ https://blog.logrocket.com/to-mutate-or-immutate/

After many years of programming I realized that creating code was easy, the difficult part was maintaining the software when the technology or the use cases changed. Looking for a way to mitigate this I found that Functional Programming has several concepts that maximize reuse while still being flexible enough to accept change and be resilient to failure. In my work, I introduced some beginning concepts such as pure functions, sum types and some simple algebras like Maybe and Task. We used TypeScript, that has some support to represent those concepts but it's not as strict as I would want it to be. In my personal time, I program with more strict languages, such as PureScript, that enforces your code to be pure and reduces the chances of making a runtime mistake.

At Acamica, I worked in a large codebase using AngularJS. Our main product was an online platform that helped our students learn trough interactive videos and code challenges. We started the project in Angular 1.2, and at that time there were no libraries to help us with the video experience. So I created and open sourced a video player that was capable of reproducing both from youtube or a direct source, and present custom components on top of the video to have a more interactive experience. When the Angular team announced the second version, I started the migration to TypeScript and refactored the player using rxjs.

One of the problems we had at Acamica was that our development stack differ from production so we runned several times into "It works in my machine". Also, we didn't have staging and at the same time we wanted to move from a monolith PHP backend to a Node microservice arquitecture. We decided to migrate to Docker and Swarm and I was in charge of the migration process.

While being CTO of Acamica I had to wear many hats, including devops. I had to create and maintain the infrastructure, which required me to use services like EC2, S3, Aurora and EFS. Initially we had a monolith of 2 servers using a PHP backend, but I drove the migration to a microservice architecture using Docker Swarm.