Teng Siong Ong, Software Developer in San Francisco, CA, United States
Teng Siong Ong

Software Developer in San Francisco, CA, United States

Member since October 3, 2013
Teng Siong is a freelance developer and entrepreneur who has helped build applications with millions of users. He started a company after his freshman year, which was later acquired. He has extensive experience working with early stage startups and helping them to build quick prototypes for market validation.
Teng is now available for hire




San Francisco, CA, United States



Preferred Environment

MacVim, Git, MacOS

The most amazing...

...thing I've created was a company my freshman year at college, which I then sold 6 months later.


  • Co-founder

    2012 - 2013
    Apartment 7, Inc.
    • Created 4 early prototypes for market validation.
    • Created an online video chat feature that supports realtime user tracking.
    • Created a web app that scaled up to 80k+ profiles in less than 1 month.
    • Built a payment system to start charging users.
    • Built a matching algorithm to suggest right matches to users.
    Technologies: JavaScript, Objective-C, Ruby on Rails (RoR)
  • Co-founder

    2011 - 2012
    Serenpidity Machine, Inc.
    • Created the client-side JavaScript-based web application with Backbone.
    • Iterated on the back-end API.
    • Iterated on the iPhone client.
    • Created the internal metrics dashboard.
    • Added metrics tracking for both the iPhone app and the web app.
    Technologies: Objective-C, Ruby on Rails (RoR), JavaScript
  • Software Contractor

    2010 - 2011
    FLOChip, Inc.
    • Developed a full-scale eCommerce prototype.
    • Developed a custom content management system.
    • Developed a music streaming service: Chinese Pandora.
    • Managed the launch of a website from a public company.
    • Managed the redesign of a client project.
    Technologies: JavaScript, Objective-C, Ruby on Rails (RoR)
  • Mobile Developer

    2009 - 2010
    Loopt, Inc.
    • Iterated on the iPhone app that had millions of users.
    • Built the first paid-only feature into the iPhone app.
    • Added metrics tracking for the iPhone application.
    • Iterated on the chat features on the iPhone app.
    • Worked on the product to get feedback from the users.
    Technologies: Objective-C
  • Co-founder

    2009 - 2009
    GraffitiGeo, Inc.
    • Built the early iPhone prototype that got us into Y Combinator.
    • Created a real-time heatmap showing users who checked in places.
    • Developed the back-end API for the mobile clients that supported up to 50k users.
    • Programmed the internal metrics dashboard.
    • Iterated on the design for the website and the iPhone client.
    Technologies: Objective-C, JavaScript, Ruby on Rails (RoR)



  • Languages

    Ruby, JavaScript, Objective-C, Java, SQL, Python
  • Frameworks

    Ruby on Rails (RoR), React Native
  • Libraries/APIs

    Backbone.js, Facebook API, Stripe, jQuery, React, Node.js
  • Platforms

    Android, iOS, MacOS
  • Storage

    Redis, PostgreSQL, MongoDB
  • Other

  • Tools

    MacVim, Git
  • Paradigms

    Agile Software Development


  • Bachelor Degree in Computer Science
    2008 - 2012
    University of Illinois at Urbana-Champaign - Urbana-Champaign, Illinois

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