Janusz Gregorczyk
Verified Expert in Engineering
Software Developer
Janusz is an experienced iOS developer who has developed more than 40 iOS apps from scratch over the last few years while working on many more. Before that, he was a co-founder of Gameleons (in its prime time, one of Poland's biggest mobile development teams) and worked on over 50 mobile Java games.
Portfolio
Experience
Availability
Preferred Environment
Git, Xcode
The most amazing...
...thing I've coded was a Doom-style game engine in mobile Java.
Work Experience
iOS Developer
Doist
- Developing iOS apps in Swift.
Independent software developer (self-employed)
codesize
- Worked remotely with businesses worldwide.
- Specialized in mobile application development, particularly the iOS platform.
- Developed about 40 iOS applications from scratch and worked on many more.
Senior iOS Engineer
Bright Mediums
- Developed and maintained of several challenging iOS projects.
- Worked in an Agile team.
- Provided expertise in multithreaded CoreData, CoreLocation, UIKit.
Senior iOS Developer
AppwoRx LLC
- Worked on a 2.0 version and subsequent enhancements of a clinical photography application.
- Almost completely rewrote the iOS code base, developing an iOS universal application, heavily interfacing with a REST-ful back end.
Mobile Hero
Brothers Media
- Developed several beautifully designed iOS universal applications featuring in-app purchases, maps, and push notifications.
CTO, Co-founder
Gameleons Sp. z o.o.
- Managed development and R&D activities of one of Poland's top mobile game studios of the time.
- Involved in over 40 J2ME projects, from conception to post-production maintenance.
- Developed several game engines, a local Bluetooth multiplayer solution, and a core porting technology.
C/C++ Programmer / Contractor
InterActive Vision Mind Beacon Sp. z o.o.
- Helped port two arcade simulator games from PC to the PlayStation 2 platform: Operation Air Assault and Pacific Warriors 2.
- Worked on platform and compiler porting of large Visual C++ code base to PS2 and GCC.
- Implemented PS2-specific features.
- Performed subsequent optimization and bug fixing.
C/C++ Programmer
InterActive Vision Mind Beacon Sp. z o.o.
- Programmed a variety of applications on Palm OS and Windows Mobile.
- Developed game back end, parts of user interface and various other components of the PC game Airlines 2.
Experience
Zonnesimulator for Eneco
I worked on UIDocument-based renewable energy calculator and used complex CoreAnimation transforms.
RxPhoto for AppWorks LLC
http://myappworx.com/rxphoto/Ahold Experience for Ahold Europe
Used Vuforia SDK, OpenGL, and AVFoundation for AR video display.
The Bovenkant van Nederland for Scriptum Publishers
Developed a custom interface with lots of CoreAnimation, MapKit, IAPs, CoreLocation.
Dinosaurs for Kids for Potrus Publishing Sp. z o.o.
Skills
Languages
C, Objective-C, C++, JavaScript, Python, Java, C#, Swift
Frameworks
ZURB Foundation, UIKit, Cocoa, AFNetworking, Core Data, Cocos2d, iOS SDK, Core Location, MapKit
Platforms
iOS, J2ME, PlayStation, Android
Libraries/APIs
Core Animation, Parse SDK, CocoaPods, OpenGL, WinAPI
Tools
Instruments, Interface Builder, Microsoft Visual C++, GCC, Subversion (SVN), Bitbucket, GitHub, Git, TextWrangler, Xcode
Paradigms
Continuous Integration (CI), REST
Other
Multithreading, In-app Purchases, RenderWare, Palm OS, AVFoundation
Education
MSc Degree in Electronics Engineering
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie - Szczecin, Poland
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