Alejandro Hernandez, Developer in Córdoba, Cordoba, Argentina
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Alejandro Hernandez

Verified Expert  in Engineering

Serverless Developer

Córdoba, Cordoba, Argentina
Toptal Member Since
October 30, 2012

Alejandro got his bachelor's degree in software engineering in 2005 and has since been working for software companies of all sizes from all around the globe as a freelancer. Currently, he enjoys working as a full-stack architect in JavaScript projects, where his experience and his deep understanding of architecture and theory are most impactful.


Node.js, JavaScript, HTML5, Web Development, Full-stack, Expo, React Native...
Babel, Serverless, Node.js, JavaScript, HTML5, Web Development, Full-stack...
Node.js, JavaScript, HTML5, Web Development, GraphQL, React




Preferred Environment

Node.js, Git, Atom, MacOS

The most amazing...

...thing I've built is a multi-player 3D Pong game in HTML5: distributed UX, rendered in WebGL/Three.js, controlled by accelerometers, connected with Socket.IO.

Work Experience

Front-end Engineer

2018 - 2018
  • Built a simple, high-performance React application.
  • Created pixel-perfect designs with styled components.
  • Integrated a context API to handle application state.
  • Developed a small React Native application (using Expo) as a proof of concept.
  • Wrote a custom REST API library with Context API.
Technologies: Node.js, JavaScript, HTML5, Web Development, Full-stack, Expo, React Native, React

Solution Architect

2017 - 2018
  • Provided server-side rendering with React and AWS Lambda and AWS API Gateway to reduce cost from idle server time.
  • Implemented GraphQL Data Loader for Postgres SQL tables to reduce DB load.
Technologies: Babel, Serverless, Node.js, JavaScript, HTML5, Web Development, Full-stack, GraphQL, React, AWS Lambda, Architecture

Front-end Engineer

2017 - 2018
  • Created the admin application of the web store in React.
  • Replaced Redux with Apollo Client for GraphQL against a Ruby back-end.
  • Created a HOC architecture to reuse common GraphQL functionality for listing and filtering.
  • Created our own custom UI library with styled components.
  • Used HOC for form manipulation.
Technologies: Node.js, JavaScript, HTML5, Web Development, GraphQL, React

JavaScript Front-end Engineer

2016 - 2016
DBMS Insight
  • Worked with a React/Redux environment on a major enterprise product already in production.
  • Helped integrate charts libraries based on D3 and React.
Technologies: Babel, Node.js, JavaScript, HTML5, Web Development, D3.js, Redux, React

Full-stack JavaScript Engineer

2015 - 2016
  • Created a new front-end app based on React and Redux.
  • Added a Hot module replacement plugin to Webpack.
  • Worked with legacy code on the server side, able to understand the principles behind it and make it work again.
Technologies: GraphQL, JavaScript, HTML5, Web Development, Full-stack, MongoDB, Express.js, Node.js, Redux, React

Front-end Engineer

2013 - 2014
  • Created reusable D3.js charts using Raphael.js to draw SVG on browsers.
  • Handled responsive design layouts for views.
  • Implemented reusable components for UX using jQuery.
  • Created an xQuery Selector generator from an HTML Element DOMNode.
  • Created a Pop CSS editor for elements.
Technologies: Node.js, HTML5, Web Development, Raphaël, D3.js, jQuery, JavaScript

Technical Leader

2011 - 2013
  • Did advanced JavaScript functional programming.
  • Designed a MongoDB database.
  • Created single-page apps with Backbone.js and Ember.js.
  • Developed software using RESTful APIs with Node.js and Express.js.
  • Handled JavaScript UX framework prototyping.
Technologies: Backbone.js, Express.js, Node.js, MongoDB, HTML5, JavaScript

Business Intelligence Consultant

2008 - 2011
America Movil (AMX)
  • Developed a reporting and decision support system.
  • Designed the data warehouse.
  • Implemented an ETL process.
  • Designed reports and data visualization.
  • Configured SharePoint.
Technologies: SharePoint, PL/SQL, SQL Server Reporting Services (SSRS), SQL Server Analysis Services (SSAS), SQL Server Integration Services (SSIS), Microsoft SQL Server

An Introduction to Full-stack JavaScript
An article I wrote on how to develop applications end-to-end using only JavaScript from the client side to the server side, and even as a query language to the database side. The article was syndicated by Smashing Magazine.

Toptal Academy - React.js
I was in charge of the Toptal Academy for React.js program were we help other toptalers to understand new technologies

Toptal Academy: AngularJS

A crash course on AngularJS that I taught for the Toptal community in Córdoba.

Toptal Buenos Aires JavaScript Conference

A talk on ECMAScript 6 and Koa.js using generators, which are the most fascinating feature of ES6.

Bucefalo Base System | Class Definer for JavaScript
Bucefalo Base System is a class definer for JavaScript that handles class definition and asynchronous module definition. The complete code and tests performed using Mocha are available in the link above.


I created an ASCII Cam to create ASCII art from live video from the web cam.

Augmented Box

A simple augmented reality game to hit the character on the screen controlling the ball using this marker:
2000 - 2005

Bachelor's Degree in Software Engineering

Catholic University of Cordoba - Cordoba Argentina


React, Node.js, Backbone.js, D3.js, Polymer, jQuery, Raphaël, WebRTC, Socket.IO, EaselJS, WebGL, Three.js, jsSHA, RequireJS, YUI, Handlebars


Webpack 2, Babel, Webpack, Node Inspector, Gulp, Grunt, Atom, Expo, Amazon Elastic Container Service (Amazon ECS), AWS IAM, Git, GitHub, Solr, Jenkins, Apache, Mercurial, Adobe Fireworks, Redmine, Jira, Mocha


Redux, Express.js, Laravel, Flutter, Connect.js, React Native, AngularJS, PixiJS, Ember.js


GraphQL, ECMAScript (ES6), JavaScript, HTML5, Sass, ES7, Less, SQL


Business Intelligence (BI), Functional Programming, Agile Software Development, REST, Asynchronous Programming, Prototype-based OOP, Parasitic Inheritance


SQL Server Integration Services (SSIS), SQL Server Analysis Services (SSAS), SQL Server Reporting Services (SSRS), PL/SQL, Amazon S3 (AWS S3), Amazon DynamoDB, Oracle PL/SQL, Microsoft SQL Server, MongoDB, Redis, NoSQL, MySQL


SharePoint, MacOS, Amazon EC2, AWS Lambda, Docker


Serverless, Full-stack, Writing & Editing, Web Development, Architecture, Apollo, Amazon API Gateway, Ajax, DOM, Web Services

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