My name is Robin Christ. I do Freelance Consulting work for a living. I consider myself a part-time nerd, professional impulse buyer and ADHD-and-energy-drink-induced-hyperfocus-enjoyer.

Below will follow a collection of $random things I do for a living and hopefully know well enough to put out there without any shame.

Want to contact me about consulting work, feedback on a blog article or just wanna chat? Head over to Contact & PGP!

Networking crimes & Wireless infrastructure (click for details)
  • Primarily Datacenter and Enterprise networking
  • I’m well versed in BGP, EVPN-VXLAN, modern network architectures, etc..
  • I like to push things to the limit, especially on older used Enterprise hardware - hence the crimes (eBGP everywhere!!)
  • I know a lot about the inner workings of Mellanox MLNX-OS / Onyx, Cumulus Linux, Arista EOS, Brocade / Ruckus FastIron, Ruckus SmartZone, etc…
    • I have absolutely not gone all out with reverse engineering them…
  • I know (and prefer) the following brands:
    • Mellanox (NVIDIA) and Cumulus Linux
    • Arista
    • Brocade / Ruckus
    • Juniper
  • I also do a good amount of Wireless infrastructure stuff
    • Primarily with Ruckus APs & SmartZone
  • Cilium (for Kubernetes) is a technology I’m using frequently
Acoustics: Waveformers, Waveguides, Horns, Simulation Software,… (click for details)
  • Loudspeaker (parts) development
    • I have kind of specialised in Waveformer technology
      • A waveformer is the central part in modern Line-Array speakers
      • A waveformer (usually) transforms the round exit of a compression driver to a rectangular slit ready to be coupled to a waveguide
      • A waveformer’s central performance metric is how well it produces an isophase wavefront at the rectangular slit exit
    • I have also kind of specialised in Waveguide and Horn technology
      • I develop custom Waveguides and Horns with exceptional directivity control (i.e. very constant directivity!)
      • I do this by utilizing advanced simulation and optimization techniques as well as years and years of experience
      • Usually the distinction between Waveformer, Waveguide and Horn is not clear, so I have made up my own definitions:
        • A Waveformer is the part that transforms the round compression driver to a rectangular slit in a Line-Array or scalable point source speaker
        • A Waveguide is a part that is purely meant to provide directivity control, often placed after a Waveformer or used in Hi-Fi applications together with dome tweeters
        • A Horn is a part that provides loading for a loudspeaker chassis, it is an impedance transformer and also provides directivity control for Mid / High-Frequency applications
    • Simulations
      • Like room acoustics, loudspeaker chassis motors, entire loudspeaker chassis, waveguides, waveformers, horns, etc…
    • I can also assist with loudspeaker chassis development
    • (Customised) measurement / acoustic data postprocessing, visualisation,…
    • Also the complete package, including (digital) preset creation, etc…
  • (Custom) Simulation Software is another thing I have specialised in
    • I have developed custom GPU-accelerated physically-based acoustic simulation software based on the Boundary Element Method
    • I have also developed custom direct sound simulation software (also called “Prediction Software”) for end-user applications
      • I believe that my components (e.g. the vectorized balloons interpolating amplitude / phase) are still the fastest on the market, by a huge margin
      • Prediction Software is usually proprietary software from PA loudspeaker system vendors where end users can predict the performance of their loudspeaker deployments
  • Sometimes I do System Technician work for Live Sound Reinforcement
Software Development: C++, CMake, Conan, Cloud Native,… (click for details)
  • All kinds of software development work
    • C++ - Yes, this is actually my preferred / main language and I know a thing or two
      • I prefer decently modern C++ (C++17 / C++20) and the LLVM ecosystem
      • I’ve been using C++ for around 11 years now (since 2014 if I remember correctly)
      • Conan for dependency management
      • CMake for build processes
    • Like almost all people I consider skilled developers, I know a lot more languages, like:
      • TypeScript / JavaScript
      • Python
      • Golang
      • Java
      • etc…
    • Those are not my main languages so I’m not perfectly fluent in them - but I can always read and understand them, and learn what I need sufficiently quick if required
    • Cloud Native software
Performance Engineering, GPGPU & HPC (click for details)
  • This deserves an extra point separate from “All kinds of software development work”
  • I love optimizing software, particularly numerical stuff, but also low latency tasks for HFT (High Frequency Trading)
  • SIMD and Intrinsics is where I feel home, https://godbolt.org/ is my second home
  • I prefer CUDA (My roots are in OpenCL, but OpenCL seems pretty much dead…)

…and even more stuff, like

  • Temporary infrastructure for events
  • Reverse Engineering
  • Electronics, Embedded Hardware
  • CAD (primarily Autodesk Inventor)
  • Lifting heavy iron weights 🙂