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Kai Koehn, Software Developer in Den Haag, Netherlands
Kai Koehn

Software Developer in Den Haag, Netherlands

Member since June 27, 2019
Kai has over ten years of experience in programming from embedded systems engineering for motor engines to scalable web architectures handling TB of data. He is passionate about challenging problems that require researching in-depth math or complicated algorithms to create reliable solutions that create a wow factor for clients and users.
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Portfolio

  • AcodeIT
    Three.js, Pandas, NumPy, Django, Express.js, GraphQL, React, TypeScript
  • VanBerlo B.V.
    Unity, Bluetooth LE, TensorFlow, React, Express.js, NumPy, ESP32, Arduino
  • Robert Bosch GmbH
    Python, JavaScript, C#, .NET, Perl, C++, C

Experience

Location

Den Haag, Netherlands

Availability

Part-time

Preferred Environment

Zsh, Shell, Python, TypeScript, React, VS Code

The most amazing...

...application I've built was a smart golf ball with automated signal processing, advanced physics, test bench, and iOS Watch App and Lightning connectivity.

Employment

  • Co-founder, Full-stack Developer

    2016 - PRESENT
    AcodeIT
    • Collaborated with a Taiwanese Bluetooth beacon producer to develop an indoor localization and tracking solution for industrial IoT applications.
    • Designed and developed the project management web application with embedded video conferencing via WebRTC for a German consultancy.
    • Designed and developed a client portal for a law firm to manage cases, and reuse previously created case templates.
    • Developed an HTML5 UI for a pick-and-place application for a robot. The UI communicates with ROS to monitor and set different parameters of the system. It also has a 3D viewer to visualize point-clouds from a depth-camera, and allows users to set ROI and other parameters within the 3D viewer (Three.js).
    • Designed and developed an ERP system for a French resource trader, that allows forecast management, HR tooling, CRM tooling, and basic knowledge management.
    • Developed a trading simulation game in cooperation with the TU Delft for their serious gaming program track.
    Technologies: Three.js, Pandas, NumPy, Django, Express.js, GraphQL, React, TypeScript

  • Full-stack Developer

    2015 - 2018
    VanBerlo B.V.
    • Digitized analog water meters, with an embedded camera system that transferred and automatically extracted the readings to Cloud storage.
    • Developed a modular prototyping system for a car demonstrator to interact, orchestrate, and debug multiple hardware and sensor nodes (computers, tablets, phones, and embedded systems with Wi-Fi).
    • Developed an AR mobile app to make a book more interactive.
    • Created a prototype from an embedded 9DoF sensor that publishes the data via BLE to a mobile phone game developed in Unity.
    • Designed and developed middleware on a boat system to separate a hardware supplier and UI, allowing other parties to develop applications and modules on top of that API.
    • Developed an app and toolchain around a smart golf ball solution to record and process radar signals, which are then transferred to a Cloud application to perform pattern matching, and to determine the speed, distance, and rotational speed of the golf ball.
    Technologies: Unity, Bluetooth LE, TensorFlow, React, Express.js, NumPy, ESP32, Arduino

  • Software System Developer

    2010 - 2015
    Robert Bosch GmbH
    • Analyzed and implemented customer requests, and focused on the low-level functions of the motor engine.
    • The process included: DevOps (Custom tool developments for build process), custom tool development for resource analysis, knowledge management using Wiki, networking and CAN communication, and immobilizer and anti-tampering protection.
    Technologies: Python, JavaScript, C#, .NET, Perl, C++, C

Experience

  • Pick-it N.V.
    https://www.pickit3d.com/

    Rebuilt the HTML front end in TypeScript and React. Designed and developed the front-end architecture to handle complex states and interactions with the Robot Operating System (ROS). Added support for the modern JavaScript ES6 syntax like async, await, and decorators.

  • TailorFlow

    Application for legal client management developed in cooperation with a Dutch law firm.

  • Project Management Tool for German Consultancy
    https://kom-neun.de/

    This is a tool that allows the support of the consultancy process with multiple clients. It includes features such as file upload, event planning, to do lists, and conferencing.

Skills

  • Languages

    TypeScript, JavaScript, Python, C, ECMAScript (ES6), C++, Perl, CoffeeScript, GraphQL, PHP, C#

  • Frameworks

    Django, Django REST Framework, .NET, Express.js, Unity

  • Libraries/APIs

    React, MobX, Graphene-django, Python Asyncio, NumPy, Pandas, Node.js, Three.js, TensorFlow, WebRTC, Office API

  • Platforms

    Visual Studio Code, Amazon EC2, Firebase, Arduino, Bluetooth LE, Heroku, Adobe Suite

  • Other

    Back-end Development, Linux Servers, Microsoft 365, ESP32, Linux Device Driver, WebSockets, Framer Prototyping, V-Model

  • Tools

    MQTT, Webpack, VS Code, Shell, Zsh, GitHub, Jenkins, Sketch, Prisma

  • Paradigms

    DevOps, Agile, Scrum

  • Storage

    PostgreSQL, Elasticsearch, MySQL, MongoDB

Education

  • Master of Science Degree in Management of Technology - Specialization in ICT
    2012 - 2015
    Delft University of Technology - Delft, Netherlands
  • Bachelor of Engineering Degree in Computer Engineering
    2007 - 2010
    Baden-Wuerttemberg Cooperative State University (DHBW) - Stuttgart, Germany

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