challenge cryptocurrency javascript nodejs postgresql react sessions

Solution for the QR Capital Challenge

A simple and elegant website to select and track your favorite cryptocurrencies

_{Quick links for interviewers:}

Preview | Features | How to run | Competences | About me

_{This program was built with ❤︎ by Gabriel Castro}

Preview

Features

Easy run: Dockerized for your convienience and value of your time ❤
Individual user accounts - Have your own Dashboard
Beautiful and responsive layout
Cryptocurrency search & track using CryptoCompare API
Get the 24-hours price change in any currency! Updated on each 5 seconds.

How to run

I deployed this application on DigitalOcean using ci/cd! If you want to test the application, just enter this website: http://gabrielcastro.codes/

To run this applications, you must have Docker installed in your computer.

Read more about how to Install Docker here: Docker Installation Guide

If you already have docker installed and running, all you have to do is clone this repository, open terminal/bash and write the docker compose up command:

Docker compose up --build

After the containers are created, you can access the application using the following link: http://localhost:3000/

Competences

There are several hard skills which I want to prove I have in this challenge:

NodeJS/React Stack

This program is made using NodeJS in the back-end and React in front-end.

I have already done other servers for games in my years of experience in full-stack development using many frameworks in my company (Gunbound GITZ) and this challenge allowed me to show a good understanding about how software works.

Sessions

I made my own server-side sessions implementation, which was inspired by the same solution I made in other projects.

This solution stores a session cookie in the database and browser and uses it as authentication. It's implemented in a way that allows further control of sessions for the user, storing in the database information about the session such as IP, browser, and OS. This approach allows the creation of a page where the user can see all sessions and remove specific sessions. Similar to what is done in modern apps such as Facebook and others.

Understanding of Cybersecurity for any software

I want to show in this challenge that I have a good understanding about security-related practices while building a full stack app because I used to exploit them in order to make gamehacking when I was young. Since a very young age, I was a cheater(in online games) and this helped me to have a decent knowledge about which verifications must be in backend and which should'nt.

For online games, the choose of which verification should be on front or back-end is a very important skill in order to create a secure app (the best security is the code). That's a knowledge that is true to any software (not only games) and that's the competence I want to show here: I'm capable of see when the software have inconsistent checks on frontend and when the backend shouldn't trust the client.

Fluent english writing/reading skills

I have years of experience working with multicultural teams in asynchronous chats.

The main language of the challenge is english-only to show my experience on creating software and documentations in english language so anyone can contribute and do maintenance.

Automated test coverage and Test-driven development

I am already used to think a lot before writing any code.

This program was made using TDD/BDD/DDD methodology and I used Jest to create the tests.

High level of adaptability and very fast learning curve

I'm used to adapt myself.

This solution is a complete solution to show my high level of adaptability and very fast learning curve. I accomplished every single topic of the challenge to prove that I can learn fast in order to deliver a project. I've done this many times in my company, and like any entrepreneur, I had to learn a lot very fast.

SQL (PostgreSQL)

As mentioned in the challenge rules, we used postgreSQL for database.

I have more than 10 years of experience working with SQL in many databases(mySQL, SQL Server, PostgreSQL, etc).

Software design patterns (MVC, SOLID, etc)
Conventional commits

About me

I'm Gabriel Castro and I love coding softwares!

_{I'm a Lifelong learner, software developer, I study economy, blockchains, tech, astronomy and history. Intelectually generalist, I have interests in many fields of science.}

I talk about Bitcoin, web3, and economy on my twitter:

_{My twitter is worth to check since it has 2 years of recorded proofs of my true love about economy, bitcoin and my own travel through the bitcoin's rabbit hole.}