Lucas Souza, Developer in São Paulo - State of São Paulo, Brazil
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Lucas Souza

Verified Expert  in Engineering

Software Developer

São Paulo - State of São Paulo, Brazil
Toptal Member Since
April 19, 2014

Lucas' past projects provided him with a variety of developer skills, which he knows how to apply to almost all levels of performance, availability and scalability issues. He worked with a lot of technologies which allows him to use the right language to solve the right problem.


Amazon Web Services (AWS), DevOps, Chef, Backbone.js, Ruby on Rails (RoR)
Scala, Sinatra, MongoDB, Redis, Memcached, Varnish, RabbitMQ...
JavaScript, Ruby on Rails (RoR), Java




Preferred Environment

Git, Google Chrome, ITerm, Vim Text Editor, MacOS

The most amazing...

...thing I've coded was the new CMS of In doing so I used a lot of technologies like RabbitMQ, EventMachine, Scala, Rails, Sinatra, Solr, Varnish, etc.

Work Experience

Software Engineer

2013 - PRESENT
  • Supported an existing website built with Ruby on Rails, MySQL and AWS.
  • Created a new mobile application using Backbone and PhoneGap to facilitate the communication between customers and clients.
  • Created recipes to automate the existing infrastructure of any environment.
  • Created a new payment system, integrating with MoIP and PayPal.
  • Created daemons responsible for processing messages from SQS. Used REST to keep the system decoupled.
Technologies: Amazon Web Services (AWS), DevOps, Chef, Backbone.js, Ruby on Rails (RoR)

Software Engineer

2011 - 2013
  • Created a platform using ImageMagick to support images in different formats and sizes.
  • Created the new CMS interface using Rails and JavaScript, for journalists to use everyday.
  • Created a gem to paginate queries on databases using Mongoid and MongoDB.
  • Created the infrastructure to cache every page using Varnish and HTTP Headers.
  • Created a gem that enables REST communication between CMS and Delivery platform.
Technologies: Scala, Sinatra, MongoDB, Redis, Memcached, Varnish, RabbitMQ, Ruby on Rails (RoR)

Developer, Instructor and Consultant

2009 - 2011
  • Taught courses in: Basic Java, Web Java, EJB Java, Agile (XP and Scrum), Ruby on Rails and Rspec.
  • Worked as Chief Editor for InfoQ Brasil. Responsible for translating, creating and reviewing technological articles.
  • Wrote the first Brazilian book about Ruby: "Ruby a linguagem mais divertida".
  • Created two courses, one on Hibernate and one on JSF.
  • Supported open-source projects like: Caelum Stella, Restufie, etc.
Technologies: JavaScript, Ruby on Rails (RoR), Java

Java Developer

2007 - 2009
  • Supported a WMS system using JSP, Servlets, Struts 2.
  • Created a system using Google Web Toolkit, Hibernate and Oracle to manage the main Education Company in Brazil.
  • Created a system using Google Web Toolkit, GXT and Hibernate to track the company's assets.
  • Coached other developers, teaching them how to use Google Web Toolkit and how to test, using JUnit.
  • Performed a big refactoring on WMS system to replace Struts 2 with Vraptor.
Technologies: VRaptor, Apache Struts 2, Jakarta Server Pages (JSP), Google Web Toolkit, Java

Java Developer

2006 - 2007
Visual Midia
  • Supported an existing system responsible to manage the school students' information, using SWT and Prevayler.
Technologies: JUnit, Prevayler, SWT, Java

CMS for is the second Web Portal from Brazil and they had a poor CMS written in Java.
My team worked to build a new solution to replace it, using Ruby, Event Machine, RabbitMQ, Varnish, and various other tools. Today the project is still growing, so that proves our effort in building a quality system was worth it.


Ruby, JavaScript, Java, Unicorn, SQL, Scala


Capybara, Ruby on Rails (RoR), Google Web Toolkit, VRaptor, Sinatra, Jakarta Server Pages (JSP), JUnit, Apache Struts 2, Padrino, AngularJS, JSF


Rack, Backbone.js, EventMachine, jQuery, Underscore.js, Backbone.Marionette, Redis Queue, Prevayler, Amazon API, SWT, AMQP, Mahout, Facebook API, Twitter API, Google Maps


Amazon Simple Queue Service (SQS), RSpec, Vim Text Editor, RabbitMQ, MacVim, ITerm, Chef, NGINX, RVM, Eclipse IDE, Varnish, Git, Capistrano, GCC, Google Cloud Messaging, SBT, Nagios, Passenger, MySQL Workbench


Agile Software Development, Object-oriented Programming (OOP), Test-driven Development (TDD), Plain Old Ruby Object (PORO), Behavior-driven Development (BDD), Functional Programming, DevOps


MongoDB, Redis, MySQL, Memcached, SQL Server 2000, HDFS


New Relic, MacOS, Ubuntu, Google Chrome, Amazon Web Services (AWS), Oracle, Windows, iOS


Relational Database Services (RDS), Mailchimp API

2003 - 2007

Bachelor's Degree in Computer Engineering

Ribeirão Preto University - Ribeirão Preto - SP