Sebastian Alff

01 About

I'm a freelance software developer in Munich, and Interactive Impressions is the name I work under. It's just me: you talk to the person who writes the code.

Most of my work is web platforms and the systems behind them: databases, authentication, reporting, and the cloud infrastructure they run on. My most recent larger project is a data platform used across about 25 companies of the DEAG group.

Before I wrote software full-time, I spent years in robotics. At KUKA I planned automated assembly for Airbus; at Franka Emika I built robot applications and an OPC UA server. That's why robotics companies hire me for fleet management and robot interfaces today.

I studied mechanical engineering, and I still like building physical things. I design parts in CAD, print and mill them, and write firmware for small controllers. I'm taking on more projects where software meets hardware.

• A

  Web platforms and data

  Business applications, dashboards and internal tools with Next.js, PostgreSQL and Supabase. Authentication, multi-tenant data, reporting, and the Azure, AWS or GCP setup they run on.

• B

  Robotics software

  Fleet management, robot applications and web interfaces for automation: VDA 5050, ROS, OPC UA. More than ten years in robotics.

• C

  Prototypes and CAD

  Small embedded controllers, 3D-printed and CNC-machined parts, and CAD in the browser. Mechanical engineer by training, author of OpenCascade.js.

TypeScript/ C++/ Python/ Rust/ React/ Next.js/ PostgreSQL/ Supabase/ Keycloak/ Azure/ AWS/ GCP/ Docker/ Terraform/ ROS/ VDA 5050/ OPC UA/ FreeCAD/ Fusion 360/ KiCad/ 3D printing/ CNC

02 Experience

1. 2019 - today

   Freelance software developer · Interactive Impressions

   Web platforms, robotics software and CAD in the browser for clients in robotics, entertainment, energy and consumer electronics. Full-time since 2021.

   • Next.js
   • PostgreSQL
   • Azure
   • VDA 5050
   • WebAssembly
2. 2019 - 2020

   Robotics engineer and software developer · Franka Emika

   Robot applications as reusable building blocks that end users configure in a web interface, and Franka's OPC UA server. Projects included a part-testing cell for Schaeffler and a five-robot assembly cell.

   • C++
   • OPC UA
   • Web UIs
3. 2014 - 2018

   Aerospace production automation engineer · KUKA Systems

   Engineering studies and line simulations for aerospace customers: the Airbus A320 final assembly line in Hamburg, the A320 Section 19 line at Premium AEROTEC, and an R&D programme with Mitsubishi Heavy Industries on automated wing sealing.

   • Robot simulation
   • Process planning
4. 2007 - 2014

   Mechanical engineering · TU Hamburg, RWTH Aachen

   B.Sc. and M.Sc. in mechanical engineering. Master's thesis on assembling flexible parts with a multi-arm robot system (grade 1.0). Research on robot kinematics and drive-train simulation.

03 Selected work

Azure · Next.js · PostgreSQL

Web platform · Data

DEAG data platform

A business data platform used across 25 companies of the DEAG group.

~130 users · 600,000 tickets

import initOpenCascade from "opencascade.js";

const oc = await initOpenCascade();
const box = new oc.BRepPrimAPI_MakeBox_2(
  10, 20, 30
).Shape();

Open source · CAD

OpenCascade.js

My open-source port of a professional CAD kernel to the browser.

930 stars · ~27k downloads / week

3D web experience

Samsung Experience Studio

An interactive showroom for Samsung's connected-living products, with a guided virtual tour.

Live on samsung.com

RP2040 · Rust · BLE

Embedded · Prototype

Remote-controlled boat

Rust firmware for two microcontrollers, a wireless protocol, and a browser remote.

RP2040 · BLE · WebBluetooth

More projects

• Fleet management for Filics

  Took over a VDA 5050 fleet manager for autonomous mobile robots and made it reliable to operate. Ongoing.

  Robotics

• TES H2 website

  Corporate website with animated storytelling and a content management system.

  Web

• Glass House Farms Experience

  An immersive 3D tour through a greenhouse, ending in an audio-visual space.

  3D web

• ClassCAD for Buerli.io

  Ported the ClassCAD C++ CAD kernel to WebAssembly so it runs in the browser.

  CAD

• Enclosure heater for a 3D printer

  A Pico W controller with an OLED menu and rotary knob that heats and ventilates a printer enclosure.

  Embedded

• Feeds and speeds calculator

  CNC cutting parameters, packaged as a plugin for the LinuxCNC QtDragon interface.

  CNC

• libclangjs

  libClang compiled to WebAssembly, used to generate the OpenCascade.js bindings.

  Open source

• CNC parts for EnHands

  Volunteer machining for a student initiative building low-cost prosthetic hands.

  Volunteering

04 Notes

• Oct 2026

  A tiny robot protocol: COBS and CBOR over USB and Bluetooth

  How a small boat gets a protocol with acknowledgements, telemetry and a watchdog, and what WebBluetooth's 20-byte writes do to it.

05 Contact

Let's talk about your project.

Tell me what you're building and where you're stuck. I usually reply within two working days.