Antoon Groenewoud, Developer in Marknesse, Netherlands

Antoon Groenewoud

Game Developer

Marknesse, Netherlands
Toptal Member Since
February 14, 2014

Antoon is a top programmer and designer with experience ranging from entrepreneur to freelancer and CTO. He is active within the games industry with a knack for novel and complex solutions and the ability to quickly integrate into any team and adapt to the problem at hand, whether it be the UI/UX, back end, or anything in between.

Antoon is available for hire
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Old Skull Games
XML, Amazon S3 (AWS S3), C#, Objective-C, iOS, Unity3D, Android, Java, Unity...
Happy Tuesday
Facebook API, Facebook SDK, XML, SOAP, JSON, PHP, Flash, Modo, Subversion (SVN)...
Deltion College
Game Development


Marknesse, Netherlands



Preferred Environment

Unity3D, JetBrains Rider, Linux, Blender

The most amazing...

...project I've coded is a fully fledged 3D game engine that supported collaborative online editing.

Work Experience

2013 - 2014

Freelance Programmer

Old Skull Games
  • Designed and wrote patching pipeline for soft patching mobile platforms depending on localization and device type filters with easy to use but extensive patch builder using an XML based DSL.
  • Consulted and provided custom tailored documentation regarding the Android platform.
  • Created a modular cross platform video player plugin for Unity3D that supports subtitles.
  • Ported Unity/iOS game to Unity/Android.
Technologies: XML, Amazon S3 (AWS S3), C#, Objective-C, iOS, Unity3D, Android, Java, Unity, Game Development, .NET, Mono
2011 - 2013


Happy Tuesday
  • Created an easy-to-use, scalable, modular tool to bundle assets for artists.
  • Assessed potential projects and new technologies and interviewed programmers.
  • Created a scalable, modular DSL for handling complicated unit values like health and the effects on them.
  • Wrote a very efficient, modular sprite loading and rendering system for a novel 3D rendering technique.
  • Designed and wrote a camera system, fog, and environmental shaders together with artists. Created an effects system and tools including efficient but impressive explosions, complicated projectiles, sound management system, and more.
  • Identified and solved many rendering bottlenecks for the iPhone.
  • Ported Pet Vegas game from Facebook to iOS with an artist. this included creating a Flash exporter that rasterized and bonified art for use within Unity3D.
  • Worked on a regression testing system and auto-building system that combined Cruise Control, SVN, Trac, and Unity3D.
  • Created five unique player characters each with unique visuals, abilities, and 25 unique skills closely together with artists and game designers.
Technologies: Facebook API, Facebook SDK, XML, SOAP, JSON, PHP, Flash, Modo, Subversion (SVN), Wikis, CruiseControl, Trac, Android, iOS, Cocos2d, Java, Objective-C, C#, Unity3D, Unity, Game Development, .NET, Mono
2008 - 2009

Assistant Teacher: Game Development

Deltion College
  • Taught first-year students the basics of everything from scripting to texture unwrapping.
Technologies: Game Development
2007 - 2008

Founder / Designer / Developer

Perfect Prefabs
  • Created a transaction tracker to learn about our customers and sales. It included a PHP back-end and web interface.
  • Researched the market; designed and created many products.
  • Created and maintained the company website including the design, art, and programming.
  • Managed the company's community and hosted live events.
  • Created many tools used for creating and selling products.
Technologies: PHP, LSL, Game Development, Mono


"Flexine" Game Engine

After joining the Games Academy, I decided to leave behind my "April" engine and start fresh. It evolved from 2D to 3D and offline to online. It ended up having a 3D renderer, animation system, particles, deferred lighting, a UI system, Lua scripting, a terrain engine, math and geometric functions, spatial partitioning, and more. It focused on online collaborative working à la Google Docs, in real-time while playing the game. At the time I did not know about Gdocs or Shark3D, which also implemented something similiar. If you were a dev you could change scripts in real time and they would update on everyone's computer. Example: Someone could play while a dev was editing how the inventory UI worked.

"Haunted Island" Tablet 3D Strategy Game

When I joined Happy Tuesday, we started creating Haunted Island in Unity3D. I was the only programmer at the time and wrote all the core systems, and later 2 more programmers joined. I joined to learn more about game development itself because I was so focused on engines. What I found especially interesting is how many states the code has to deal with and how different the quality assurance is.

"Pet Vegas" Flash to Unity/iOS Port

The client wanted to reach the mobile market with their Facebook/Flash game. I was the only developer as we ported it to Unity/iPhone/iPad in just over 3 months. It was a slot machine game that included minigames like black jack. It also sported many small unique cutscenes which presented an interesting challenge to port. It had significant Facebook integration, a strong connection with a php backend, and tried to achieve maximum graphical fidelity which is a significant challenge on iPhones. I wrote an exporter that rasterized the pre-existing animated vector graphics in Flash to bones and sprites which saved a lot of time and money.

Web Transaction Tracker

I wrote a tool that tracked transactions in Second Life for Perfect Prefabs. This way we could see what products were popular, who were our biggest costumers in terms of sales, revenue, and time periods. It had two main parts: The web user interface that was generated by PHP, and the Second Life scripts that would access a PHP web interface to store new data into an SQL Database.



HLSL, C#, Cg, GLSL, JavaScript, C++


Unity3D, .NET, Unity, Mono, Android SDK


.NET BCL, DirectX, iOS Native Libraries, OpenGL ES, OpenGL


Subversion (SVN), Blender, Google Docs, Open Office, Visual Studio, Xcode, Git, JetBrains Rider, NGINX, Jenkins


Game Development, Unity Shaders, Shaders, Unity3D Native Plugin Interface, CruiseControl, SOAP, Augmented Reality (AR), Virtual Reality (VR), Compute Shaders


Windows, iOS, Android, Linux


Amazon S3 (AWS S3), Unity Cloud Build


2009 - 2011

N/A Degree in Design & 3D Programming

Games Academy - Berlin, Germany

2004 - 2008

N/A Degree in Design Animation & Games

Deltion College - Zwolle, Netherlands