Programming · Design · Technology

Learn to code with passion

Complete, free, no-nonsense tutorials (in Spanish). Theory, challenges and resources from my university courses.

"I can only show you the door, you're the one that has to walk through it" – Morpheus

        /|      __          
       / |   ,-~ /          
      Y :|  //  /           
      | jj /( .^            
      >-"~"-v"              
     /       Y              
    jo  o    |              
   ( ~T~     j              
    >._-' _./               
   /   "~"  |               
  Y     _,  |               
 /| ;-"~ _  l               
/ l/ ,-"~    \              
\//\/      .- \             
 Y        /    Y            
 l       I     !            
 ]\      _\    /"\          
(" ~----( ~   Y.  )

Follow the white rabbit ↓

neo@matrix: ~

Wake up

ヤ = 8 1 ; ; 8 > < A ラ 3 / / カ > 6 A A ナ 7 A / < { R R 3ハ 0 4 0 A 9 = A サワ 9 7 4 マ R カ 2 2 > A 8 ハ 4 ワ 2 4 1 86 A < < 8 7 / A 3 / ラ { 2 1 3 X A タ A サ 4 ハサ A ヤ < ハ 5A R A R ; ワアラサア } ラ = 7 / ラ A ラ 3 R ナ 7 ア R < A ア R> ワヤヤ 9 カ ; / / 7 カタ A ナ / R カ A A A N ; 4 ラ = A 3 ラ2 } = 1 = 4 マ 0 A A < A A マ < ナ 7 9 ; N 6 マ 5 ハ > 8 9 7ア 0 8 ヤ = 0 ラ > 5 サ X A A R > N ア ; } = R カナサタサア }ヤ > ラ 5 A 4 > X 3 4 サラ A A ハ A 7 ナヤ } ハサワ < 9 6 A サア 4 タラ A X ; 5 C N A > { 2 4 7 7 9 = > < = A C A 5 7 N1 A / = N X ヤラ X タ A A < / 8 5 A 9 A ワ / 5 3 マ { ラ R Aナ 0 A アナ 3 ア / R マヤ N / マナ } ア A { ; ナ 1 = N 9 { X /カ } ヤ { ラヤ } < A ラ R カ / 4 X > A タ A 7 A 4 A X = R A マN N カサワ A A N ワマカ 6 9 ナ 1 6 ヤカカタ < 6 A = 7 / 3 }/ } A ハサ = < 5 9 3 7 ナササ 2 2 ヤ < ナカア C A カ ; 1 4 Rヤ < 4 カマ ; ; ラ A A 1 6 0 ラ A A > 7 A A A ; N / ワ / 1 AA 6 X C カラマア { A } C A A ヤ 9 6 3 8 ; 8 3 7 ラ / X 0 ラ

        /|      __          
       / |   ,-~ /          
      Y :|  //  /           
      | jj /( .^            
      >-"~"-v"              
     /       Y              
    jo  o    |              
   ( ~T~     j              
    >._-' _./               
   /   "~"  |               
  Y     _,  |               
 /| ;-"~ _  l               
/ l/ ,-"~    \              
\//\/      .- \             
 Y        /    Y            
 l       I     !            
 ]\      _\    /"\          
(" ~----( ~   Y.  )

Down the rabbit hole.

Text from Alice's Adventures in Wonderland (Lewis Carroll, 1865)

        /|      __          
       / |   ,-~ /          
      Y :|  //  /           
      | jj /( .^            
      >-"~"-v"              
     /       Y              
    jo  o    |              
   ( ~T~     j              
    >._-' _./               
   /   "~"  |               
  Y     _,  |               
 /| ;-"~ _  l               
/ l/ ,-"~    \              
\//\/      .- \             
 Y        /    Y            
 l       I     !            
 ]\      _\    /"\          
(" ~----( ~   Y.  )

About

Hi, I'm Andrés a.k.a Xaca Rana

Computer engineer, graphic designer and holder of a master's degree in ICT. I worked as a Fullstack engineer for 10 years at PRAGMA S.A. and I'm currently a faculty member at UPB's School of Energy and Digital Technologies.

Teaching programming, design and technology is what I'm most passionate about, and that's what I do every day at UPB.

What you'll find here

YouTube

Video tutorials

Courses I designed and shared with my students. Free, practical, no prior knowledge required, and doable from any computer. Videos are in Spanish.

despertar.js

const despertar = (n) =>  `Wake up, ${n}`;console.log(despertar('Neo'));

25 lessons

JavaScriptStart

despertar.py

def despertar(nombre):    return f"Wake up, {nombre}"print(despertar("Neo"))

14 lessons

PythonStart

Matrix.java

public class Matrix {  public static void main(String[] a) {    System.out.println("Wake up");

60 lessons

JavaStart

index.html

<main class="matrix">  <h1>Wake up</h1></main>

20 lessons

Desarrollo WebStart

University courses

Materials, workshops and assignments for the subjects I teach at UPB this semester, plus the archive of previous semesters (in Spanish).

Go to courses

Wake Up!

// The Resistance code

These are the pillars that define me. They have helped me reach academic and personal goals, and I share them so you can apply them to your life and career.

Progress
"Talk is cheap, show me the code." – Linus Torvalds. It doesn't matter how much you know if you can't show it. The compiler only gives two options: it works or it doesn't.
Concepts
See the whole picture of what you learn: what you use, how it is used and how it is built. Understanding the full process is the key to mastering it.
Ask
Always ask. No question is silly; it is an indicator of how you are learning, and you will almost always find someone to help.
Respect
Respect your peers. Teamwork beats working alone, and respect is the foundation of any relationship.
Passion
Passion keeps you awake and moving forward every day. Without passion there is no progress.
Awareness
Awareness makes you a better person: thinking of others, being empathetic, being human.

What students, clients, colleagues and friends say

He was my teacher in college. He has always been great at explaining because his classes are dynamic and hands-on. He has also been my colleague in continuing-education courses, and his experience across languages and technologies really shows.
Santiago QuinteroFrontend developer
A very curious person with a huge appetite for knowledge. Sharing it is his passion, as a teacher and as host of Coding with Friends, focused on building learning communities.
Felipe RestrepoBug bounty hunter
A programming ace who always seeks to share his knowledge with others, through his calling as a teacher and by connecting with people to keep learning and teaching.
Fabian SernaFrontend developer
A professional with a great ability to teach complex topics clearly and precisely. Being multidisciplinary, he inspires you to go beyond the conventional, highlighting creativity and technical skills. His passion and commitment stand out, both humanly and in his willingness to help.
Santiago TobónGraphic designer