Paulo Renato Campos de Siqueira, Software Developer in Brazil
Paulo Renato Campos de Siqueira

Software Developer in Brazil

Member since August 28, 2012
Paulo is a passionate developer who found in Scala a chance to leverage years of experience with Java: beginning his career as a web-based Java developer, Paulo discovered Scala a few years ago and, since then, has been expanding his capabilities (and portfolio) with every passing project.
Paulo is now available for hire


  • JCranky IT
    Java, Scala, Akka, Play Framework 2.0
  • DOit
    Java, Scala, Akka
  • IPTI
    Java, Struts, JavaServer Pages


  • Java, 11 years
  • Test-driven Development (TDD), 10 years
  • NetBeans, 10 years
  • Functional Programming, 3 years
  • Scala, 3 years





Preferred Environment

NetBeans IDE

The most amazing...

...thing I've built is a Java-based system for filing invoices through a REST API.


  • Independent Consultant

    2012 - PRESENT
    JCranky IT
    • Maintained Python-based system for processing large volume of Twitter content.
    • Created material on Akka 2, Play Framework 2, and Scala for Globalcode's software architecture course.
    • Created Scala course for Globalcode.
    • Taught Java, Scala courses for Globalcode.
    • Contributed to DOit invoice system by adding several new features and resolving existing bugs.
    Technologies: Java, Scala, Akka, Play Framework 2.0
  • Senior Scala Engineer

    2013 - 2014
    Synata (via Toptal)
    • Designed and coded an document processing system with Scala and Akka.
    • Implemented google calendar integration with Scala and Akka.
    • Cleaned and improved scala and akka code.
  • Senior Developer

    2010 - 2012
    • Developed Java-based invoicing system, implemented with REST (Jersey) and EOF.
    • Migrated components of invoicing system to Scala.
    • Supported partial migration of company systems from internal servers to Amazon EC2 and S3.
    • Worked on helper projects in Scala for internal use.
    • Migrated portion of invoice system to Akka (from JMS).
    Technologies: Java, Scala, Akka
  • Java Developer, Project Leader

    2004 - 2010
    • Developed web-based e-learning tool (both v1.0 and v2.0).
    • Developed pilot internal project for demonstrating use of Structs in company projects.
    • Provided general support for company's team development tasks.
    • Developed social-networking tool for e-learning communities.
    Technologies: Java, Struts, JavaServer Pages
  • Intern, Developer

    2002 - 2004
    NPT | UMC
    • Developed web-based systems for supporting researchers using JavaServer Pages and Java Servlets.
    • Implemented graphical plotting capabilities in systems mentioned above using applets.
    • Supported other interns in various development tasks.
    Technologies: Java, Servlets, JavaServer Pages


  • Lojinha (Development)

    Lojinha is a "small store" (auction) application that I developed using Play Framework 2 and Scala, to sell old stufff that I don't want anymore.

    It is an open source software and the source code is available in github:

  • Scaladores (Development)

    Scaladores is a community for in-person meetings in São Paulo to discuss Scala-related development and news.

  • Scaling Play! to Thousands of Concurrent Requests (Publication)
    Web Developers often fail to consider the consequences of thousands of users accessing our applications at the same time. Perhaps it's because we love to rapidly prototype; perhaps it's because testing such scenarios is simply hard. Regardless, I'm going to argue that ignoring scalability is not as bad as it sounds—if you use the proper set of tools and follow good development practices. In this case: the Play! framework and the Scala language.


  • Languages

    Scala, Java, HTML5, JavaScript, Python, CSS3
  • Frameworks

    Akka 2, Play Framework
  • Tools

    Maven, Git, SBT
  • Paradigms

    Object-oriented Programming (OOP), Test-driven Development (TDD), Functional Programming
  • Platforms

    Linux, NetBeans
  • Storage



  • Bachelor's degree in Computer Science
    2001 - 2004
    Universidade de Mogi das Cruzes - Mogi das Cruzes, Brazil

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