Patrick Pijnappel, Developer in Melbourne, Victoria, Australia
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Patrick Pijnappel

Verified Expert  in Engineering

Software Developer

Melbourne, Victoria, Australia

Toptal member since February 10, 2016

Expertise
iOSObjective-CSwiftXcodeJavaCC#ArduinoGitFull-Stack .NETMacOSJavaScriptNode.jsOpenGL
Bio

Patrick has been deeply passionate about programming since the age of 12. He is a longtime freelancer, co-founder of Archimedes, and a contributor to experimental AI research and the Swift language itself. He thrives on the really hard problems, clean architecture and advanced performance optimization. He has coded in over a dozen different languages and can pick up new languages and technologies very quickly.

Portfolio

Archimedes Calculator
iOS, Objective-C, Swift
Huddle
AVFoundation, Node.js, Swift
DKP Veterinary Clinic
iOS, Swift, Objective-C, Arduino, C++

Experience

  • iOS - 8 years
  • Objective-C - 5 years
  • Swift - 5 years
  • Java - 4 years
  • C - 4 years
  • C# - 4 years
  • Arduino - 4 years
  • Node.js - 2 years

Availability

Part-time

Preferred Environment

Git, Xcode, MacOS

The most amazing...

...thing I've developed is a next-generation graphing calculator with custom mathematical typesetting and custom symbolic solving engine.

Work Experience

Co-founder

2011 - 2018
Archimedes Calculator
  • Designed and developed Archimedes, a next-generation graphing calculator for iOS.
  • Created a unique, fully-interactive mathematical typesetting system with fluid animation.
  • Wrote a custom symbolic math solving engine with automatic unit handling.
  • Implemented high-quality plotting functionality including smooth touch-based scroll/zoom, automatic POI detection, and direct-interaction tracing, differentiation, and integration tools.
  • Began developing an advanced experimental new type of symbolic math engine.
Technologies: iOS, Objective-C, Swift

Co-founder

2016 - 2017
Huddle
  • Developed a location-based video sharing platform.
  • Figured out a way to have a performant feed of up to 16 simultaneously playing streaming video tiles.
  • Wrote frameworks for declarative endpoint specification, futures/promises, model parsing, model persistence, and change notification.
Technologies: AVFoundation, Node.js, Swift

Arduino/iOS Developer

2011 - 2017
DKP Veterinary Clinic
  • Created the software for a wifi-enabled advanced experimental operating table with Arduino-controlled electronics and an iPad interface.
  • Created the software for an experimental network of veterinary animal cells with lighting, heating, ventilation, and oxygen supply systems controlled by a distributed set of Arduinos communicating with an iPad interface.
  • Wrote a robust communication layer between a network of Arduinos and iOS devices using a simultaneous mixture of serial, I2C, and wifi channels.
  • Interfaced with a large number of different analog and digital sensors and actuators over a variety of different protocols.
  • Created a messaging system for generically binding sensors and settings on Arduinos to properties on iOS devices, automatically managing communication over a mixed channel network.
Technologies: iOS, Swift, Objective-C, Arduino, C++

iOS Developer

2015 - 2016
Péritus
  • Created an iOS front-end app for a dynamic CRM application.
  • Wrote encapsulation for communication with a legacy REST back-end with consistent error handling.
  • Created dynamic UI for display and manipulation of records with arbitrary fields of different data types.
  • Created a self-contained encapsulation of a complex workaround for broken call tracking API.
  • Created dynamically fetching browse and search functionality for working with large record sets.
Technologies: iOS, Swift

Java Developer

2011 - 2011
DelftTech
  • Developed the third version of a leading forensics application for the measurement of suspects by joining camera images with point cloud data from 3D laser scans of the crime scene.
  • Completely transformed a large, undocumented old codebase into a clean, stable, and organized one.
  • Wrote code for 3D navigation, rendering, and manipulation using OpenGL.
  • Wrote code to load, manipulate, and render large datasets in a performant way.
  • Redesigned, localized, and generally modernized the UI.
Technologies: OpenGL, C, Java

Swift Standard Library

https://github.com/apple/swift/pulls?q=is%3Apr%20author%3APatrickPijnappel
l've been one of the top non-Apple contributors to the Swift language and standard library since it became open-source. I primarily do performance optimization, rewrites, and spotting of edge cases in the standard library. Some of the more interesting ones include https://github.com/apple/swift/pull/1477 and https://github.com/apple/swift/pull/1525.

Archimedes

http://www.archimedescalculator.com
A next-generation scientific calculator with custom smoothly animated mathematical typesetting, lots of custom UI, and a custom symbolic math engine underneath.

Machino

https://github.com/PatrickPijnappel/Machino
Graduation project on an OS X application for the design of Arduino programs using finite state machines, including live runtime visualization of the executing Arduino code (Objective-C).
2011 - 2013

Master's (with Honors) Degree in Design for Interaction

Delft University of Technology - Delft, The Netherlands

2007 - 2010

Bachelor's Degree in Aerospace Engineering

Delft University of Technology - Delft, The Netherlands

Libraries/APIs

OpenGL, GNU Multiple Precision (GMP), Node.js, XNA

Tools

Xcode, Git, Adobe Photoshop, Adobe Illustrator

Languages

Objective-C, Swift, Java, C, C#, Python, JavaScript, CSS, HTML, C++

Frameworks

Cocoa Touch, Windows Presentation Foundation (WPF), Cocoa, .NET, Express.js

Platforms

iOS, Arduino, MacOS

Storage

MongoDB

Other

Computer Graphics, AVFoundation

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