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Guillermo Waitzel, Software Developer in Buenos Aires, Argentina
Guillermo Waitzel

Software Developer in Buenos Aires, Argentina

Member since September 5, 2013
Guillermo is an outstanding software engineer who is skilled in the development and delivery of iOS apps and games. He is capable of designing and deploying complete architectures, and has worked in a feature-driven capacity as well. He collaborates effectively and has also enjoyed success as a team leader.
Guillermo is now available for hire
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Portfolio

Experience

Location

Buenos Aires, Argentina

Availability

Part-time

Preferred Environment

iOS, Cocoa, Cocoa Touch, OpenGL, Xcode, Git

The most amazing...

...things i've coded are an OpenGL-based graphics engine, a rope physics simulator, an elliptical coordinate system, and a tool for 2D and 3D collision detection.

Employment

  • Lead Developer

    2016 - PRESENT
    Phelo
    • Developed an Instagram-like social network.
    • Developed a tag system for each picture.
    • Created the iOS architecture using VIPER and MVP concepts.
    • Developed a deep-link URL scheme for inter-app communication and better user experience.
    • Developed a mentions/notifications system on different parts of the app.
    Technologies: Swift, iOS, Parse

  • Lead Developer

    2016 - 2016
    CUAround
    • Developed the back-end of a social network.
    • Developed the UI/UX of a social network.
    • Integrated AWS S3 to the social network storage.
    • Implemented server architecture in AWS.
    • Set up generic graphic artifacts that are used in development of modern UI.
    Technologies: iOS, Node.js

  • Lead Software Engineer

    2015 - 2016
    QuickEats
    • Redesigned server-client architecture.
    • Redesigned the server database.
    • Improved system stability/security.
    • Supported different types of discounts.
    • Supported synchronization of the POS with the server and app, allowing to manually update tickets from POS.
    Technologies: Objective-C, Swift, JavaScript

  • Lead Software Engineer

    2014 - 2015
    Atmospheir
    • Created the architecture for a cloud-based contact management application.
    • Developed a full messaging system with the ability to share media content such as photos, videos, GIFs, and audio.
    • Implemented a dynamic notifications system, which can be adapted server-side to new formats or information types.
    • Integrated the iOS native address book into an existing app, enabling users to modify information in a different way.
    • Implemented efficient graphic effects for enhancing user experience, such as complex animations, compounded blur, image composition, and more.
    Technologies: Objective-C, iOS , Core Data, Core Bluetooth, Data Protection, Quartz Core

  • iOS and Mac OS Developer

    2010 - 2014
    Esquilax Games
    • Created an OpenGL-based graphics engine supporting 2D and 3D rendering.
    • Implemented the iOS game Climber Brothers.
    • Created a .OBJ (3D models) loader and parser for rendering 3D meshes.
    • Developed the AI for card games featuring a variable level of skill.
    • Created a step by step animation algorithm integrated with the Cocoa Framework.
    • Designed a custom level creation tool for the app Climber Brothers.
    • Added support for sharing content on social networks in all of the company's games.
    • Added realistic physics simulation via integration of Box2D.
    • Incorporated SVG support for curve creation and terrain design.
    • Created a smoothing algorithm using SVG curves and approximation.
    • Implemented rope physics using constraints and Newtonian mechanics.
    • Designed and implemented a PVP multiplayer environment for a battle game.
    • Created a particle system including generation of radial and gravity particles.
    • Created the Battle Rush game.
    • Implemented a radio streaming app.
    • Developed a server-client framework for displaying animations simultaneously on different devices.
    Technologies: Objective-C, C, C++, OpenGL ES, Box2D

  • iOS Developer

    2013 - 2013
    Wuzy INC
    • Integrated Stripe as a payment system.
    • Integrated OpenMaps into the application.
    • Designed a GPS-like route finder to display on screen.
    • Implemented signup/sign-in UI for Vines and customers.
    • Implemented custom maps annotations for improving UX.
    Technologies: iOS, Objective-C, Stripe, PubNub

  • iOS Developer

    2012 - 2012
    Oxean
    • Developed an app, Vale Puerto, for showing company port facilities in Argentina.
    • Created an app, Vale, for displaying company facilities in Argentina.
    • Supported image and video display via AVFoundation.
    • Designed a custom map interface showing different spots in the VALE facilities.
    • Implemented support for efficient scrolling around the Vale app.
    Technologies: Objective-C

  • iOS Developer

    2012 - 2012
    Portegno Apps
    • Created the Crazy Hairstyle Studio app.
    • Created a base framework for editing hairstyles in a realistic hairstyle salon app.
    • Built a multi-shading tool for blurring, coloring, and efficient rendering of images.
    • Added features for camera support, photo editing, and screenshot export to a game.
    • Added online synchronization for user-created products.
    • Designed and implemented a virtual canvas to support multiple devices.
    • Created an anchor and multi-point manipulation system for displayed objects.
    • Added support for real-time image editing by rendering images to textures.
    Technologies: Objective-C

  • iOS Developer

    2011 - 2012
    Webetico SNC
    • Supported communication with an AS400 for an iOS app.
    • Supported multithreaded loading of images to display in a catalogue.
    • Developed a framework for synchronizing local data with server data.
    • Designed and implemented a custom grid for displaying data.
    • Supported image synchronization on demand.
    • Created a trivia game that allowed possible customers to their contact information.
    • Created a multi-language app for a museum displaying information about museum exhibits.
    • Created a CRM app allowing customers to place orders online and offline.
    Technologies: Objective-C

Experience

  • Atmospheir (Development)

    Atmospheir is a social address book that lets your contacts update their information for you. Create a personalized ID (like a Twitter handle), share it with friends to connect, and exchange as much contact and social network information as you want. We'll notify you and update your address book whenever your contacts update their information. Just sit back, relax, and enjoy up-to-date contacts and free text, voice, photo, GIF, and location messaging with every Atmospheir connection.

  • CUAround (Development)

    Social Network pointed to university students, it displays regular social information but also articles of interest, news, allows the students to interact and be part of the comunity campus.

  • Quickeats (Development)

    QuickEats is an iPhone application that revolutionizes the way people order and pay at their favorite restaurants. QuickEats allows customers to browse the menu, place an order, and pay straight from their phones

  • Climber Brothers (Development)

    An iOS rope physics puzzle game.

  • Battle Rush (Development)

    An infinite multiplayer PVP runner game.

  • Crazy Hair Studio (Development)

    A realistic hairstyle simulator.

  • Chinchon (Development)

    A Spanish card game for iOS.

  • Escoba de 15 (Development)

    A Spanish card game with single and multiplayer features.

  • iJewels (Development)

    A jewelry catalogue iPad application for Cielo Venezia.

  • Wuzy (Development)

    An Uber-like system specifically designed for attending vines and events, finding them, and getting discounts on those associated Vines and places.

  • Phelo (Development)

    Phelo is a social network for sharing pictures. The concept is simple, tag the world around you. Every person, place, and thing. It’s all about expression. Go beneath the surface and truly discover why a picture is worth a thousand words. We all know filters and photo-liking are cool, but what if you could like, share, and comment on individual aspects of a picture? Now that's crazy.

    • Tag anything within a picture and associate it with a profile,
    hashtag, or location
    • Add links to your tags
    • Share photos with your friends
    • Like, share, or comment on any tag
    • Discover tags from around the world

Skills

  • Languages

    Swift, JavaScript, Objective-C, SQL, C, C++, C#, T-SQL

  • Frameworks

    Core Data, iPhone SDK, ZURB Foundation, iOS SDK, Cocoa Touch, Box2D, Unity, QuartzCore, Cocoa, JSON Framework for Objective-C, Express.js, ADO.NET

  • Paradigms

    Model View Controller (MVC), Object-oriented Programming (OOP), Design Patterns, Model View Presenter (MVP), Model View Viewmodel (MVVM), Agile Software Development, Concurrent Programming, Functional Programming

  • Platforms

    iOS, AWS EC2, Amazon Web Services (AWS)

  • Libraries/APIs

    Node.js, Parse SDK, Facebook SDK

  • Tools

    TestFlight, AWS ELB, AWS SDK, Mongoose

  • Storage

    Oracle PL/SQL, MongoDB, MySQL, AWS S3

  • Other

    iBeacon, Back-end

Education

  • Bachelor's degree in Software Engineering
    2005 - 2010
    Universidad Tecnológica Nacional - Buenos Aires, Argentina

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