Projects on the orange bench

by Dirk Grappendorf

Welcome to

This is a private Website where you can learn about my past and ongoing projects (mainly electronics and computer stuff) and other things that interest me. Look around and feel free to leave me a comment.

Featured Projects

  • Samrkant

    This work extends the IKEA-Hackant project from Robin Reiter, who reverse engineered the controller board of an IKEA Bekant motorized adjustable table. In my project i connected an ESP-12F module (ESP8266) to the Arduino, which gives us WiFi and quite some processing power to add additional IoT functions to the Bekant table.
  • Sunrise Alarm Clock

    Sunrise Alarm Clock
    A wake-up light, built with Elixir, Nerves, running on a Raspberry Pi Zero. This project explores how Elixir/Erlang OTP can be used to develop robust and thoroughly tested embedded systems.
  • 6502 Homecomputer

    6502 Homecomputer
    This is a project that I've often started, but haven't completed until now because i knew that it would take quite a long time: building my own 8-bit home computer from scratch. The idea was to design a computer like the C64, almost only using parts that were available when this computer was manufactured.
  • Caretaker - Smart Home Automation

    Caretaker - Smart Home Automation
    Caretaker is my DIY smart home automation and survaillance project. The aim is to create a totally wireless and scaleable system to control power switches (lamps and other electrical appliances) and measure values like temperatures, brightness and power consumption.
  • Analog Computer Construction Kit

    Analog Computer Construction Kit
    Inspired by Dr. Vogels Home Brew Analog Computer , this kit consists of various 100x60 cm PCB cards which can be connected together with 2.54 mm jumpers. Connect the various input and outputs of generators, adders, integrators and multipliers to compute different mathematical functions.


2017 Oct


With this panel, you can mount a Pi Foundation 7" Touch Display for the Raspberry Pi into a Eurorack system .


2017 Sep


If you like Korg Volcas and you've got a Eurorack system, you can combine them with this simple 3D printable Eurorack panel (40 HP).


2017 Apr


When implementing the Elxir Todo App and thinking about how to test the ElixirScript client code, one idea was to use an Elixir testing framework. Since the client code is also valid Elixir code, we could directly test it on the Beam VM instead of first translating it into JavaScript and then testing it in a Node.js environment.

Taking this idea one step further: Can we get server-side rendering without the need to run JavaScript code on our server and instead execute the client-side code...


About me

I'm a senior Software Architect, Scrum Master, Team Lead and Software Developer currently located in Dortmund, Germany.
I'm always interested in new innovative and challenging tasks, so feel free to browse through my resume and leave me a note.