Carlos Eduardo Ruhrwiem, Android Developer in Berlin, Germany
Carlos Eduardo Ruhrwiem

Android Developer in Berlin, Germany

Member since February 5, 2014
Carlos is a senior Android and Java developer with more than 8 years of experience in a wide variety of distributed technologies and in software development using Java. As a developer, he is interested in delivering a good experience and improving performance. As a leader, he is always encouraging people and guaranteeing that product development is going in the right direction.
Carlos is now available for hire




Berlin, Germany



Preferred Environment

Android Studio, IntelliJ

The most amazing...

...thing I've coded is file compression software that was executed at a GPU.


  • Senior Android Developer and Team Lead

    2018 - PRESENT
    Virtual Solution AG
    • Recreated an entire UI for the calendar module.
    • Introduced Kotlin to some of the modules.
    • Solved complex syncing issues.
    Technologies: Android
  • Software Developer

    2018 - 2018
    • Developed several features quickly after joining the company.
    • Ensured the frameworks being used are up to date.
    • Reduced build times by -50%.
    • Fixed several bugs.
    • Improved the UX by adding animations to some of the features.
    Technologies: Android, Git
  • Android Developer

    2015 - 2018
    • Added several features to the app.
    • Ensured quality by reducing the number of crashes reported to less then 1%.
    • Created several complex animations.
    • Refactored the entire network layer for a more robust and less complex strategy.
    Technologies: Android, Git
  • Android Developer

    2015 - 2015
    • Performed needed security updates.
    • Implemented more reliable communication with the server.
    • Updated the technology to the latest framework available.
    • Corrected performance issues.
    • Added animations and fixed UX problems.
    Technologies: Android
  • Android Developer

    2014 - 2015
    Global Personals
    • Prepared the application for publication.
    • Created an application from scratch based on an iOS version.
    • Fixed/improved an application by a previous developer.
    • Adapted the application to use Gradle Flavours so that the company could reuse more code.
    • Adapted the application to use Material Design.
    Technologies: Android
  • Associate

    2013 - 2015
    AOG Tecnologia
    • Developed a mobile application that communicates with a server and displays the changes in real time.
    • Developed cloud apps for monitoring social networks.
    • Managed the company and acquired partners and clients.
    Technologies: Java, Android, Java EE, Cloud Services
  • Android Developer

    2014 - 2014
    Seratis (via Toptal)
    • Implemented a framework for REST communication with JSON parsing.
    • Implemented a uniformed platform for SSL certificate handling.
    Technologies: Android, REST, Git, JSON
  • Android/Java Developer

    2011 - 2013
    GetNet Tecnologia (AOG Tecnologia)
    • Implemented Salesforce automation for Windows Mobile/Android mobile devices.
    • Created a loyalty program for a major fuel stations brand.
    • Contributed to the use of agile methodologies at several projects.
    • Worked on several proof-of-concept applications for mobile devices and web.
    Technologies: Android, Java, Java EE, C#
  • Java Developer

    2009 - 2010
    Stefanini IT Solutions (Dell Team)
    • Developed middleware communication between old and new systems for Dell.
    • Created web tools for batch updates on product.
    • Contributed to several other projects doing maintenance and support using Java Web and J2EE applications.
    Technologies: Java, Java EE, JSP, HTML
  • Java Developer

    2008 - 2009
    Digitel S/A
    • Developed a few clients for remote managing and monitoring network equipment.
    • Designed and helped develop a framework for building clients for new network products.
    Technologies: Java, Swing, Java EE
  • PHP Programmer

    2005 - 2007
    • Developed an online report tool for real-time routes.
    • Developed tools for extracting and importing data to the server.
    Technologies: PHP, HTML, CSS


  • Instashow (Development)

    Social network monitor that gathers images from specified hashtags from Instagram and stores them in the cloud to deliver to a mobile device. A Android device running on a TV or projector will be able to display the pictures that are being uploaded to the social networks in real-time for the event.
    The technologies used on the server are Java EE and cloud hosting by Jelastic. On the client there is a Android with connection to the internet that gathers all the images and show them beautifully at the event.

  • Stunr (Development)

    Stunr is a fun cool app for gay men that lets you share photos with people you match with. Swipe right to like someone or swipe left to skip. Only see guys near you who are also playing the game. It's the most fun you will ever have meeting fun new people.

  • Friskee (Development)

    Friskee is a fun cool app that let's you share photos with people you match with. Swipe right to like someone or swipe left to skip. Only see people near you who are also playing the game. It's the most fun you will ever have meeting fun new people.

  • Toptal Mentor
    Carlos is a mentor in the Toptal Global Mentor’s Program. This program is a partnership between Toptal and General Assembly to provide high quality mentorship for students from minority and low income backgrounds who are looking to begin their careers as professional software engineers. Carlos shows commitment to diversity in tech by mentoring a General Assembly student every week for a year, covering everything from coding tips and tricks to advice on making it in the industry.


  • Languages

    Java, Kotlin, SQL, UML
  • Frameworks

    Android SDK, JUnit, JPA, Grails, Hibernate, Spring, Spring Android, Spring Security
  • Libraries/APIs

    Android API, Parse SDK, Google Maps, Google Gson, RxJava, Facebook API, JDBC, Instagram API
  • Tools

    Android Studio, IntelliJ IDEA, Eclipse IDE, Git, Gradle, Subversion (SVN), Firebase Analytics, Google Analytics, Apache Tomcat
  • Paradigms

    Object-oriented Programming (OOP), Agile Software Development, REST, Incremental Development, Asynchronous Programming, Scrum, Pair Programming, Dependency Injection, Test-driven Development (TDD), Software Testing, SOA, Service-oriented Architecture (SOA)
  • Platforms

    Android, Firebase, Windows, Java EE, Oracle, Linux, Windows Mobile, Jelastic
  • Storage

    SQLite, Sybase, PostgreSQL, Oracle SQL
  • Other

    Google Play Store, Back-end Development, RESTful Web Services, Web Services, Software Architecture, SOAP, User Interface (UI), Apache Commons, Mobile Web, WebLogic


  • Bachelor's degree in Computer Science
    2005 - 2011
    Pontificia Universidade Católica do Rio Grande do Sul - Porto Alegre

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