Independent builder · Founder of Kroonen AI

Making AI
yours to own.

I’m Robin. I build open tools, run small systems, and train language models. This is my work, and what I learn along the way.

01 / Selected work

Meet the Libre stack.

All 5 projects
Communications

Early access

A lightweight phone desk on Cloudflare Workers and Twilio, covering calls, messaging, voicemail, IVR, and browser calling.

  • Calls + SMS/MMS
  • Voicemail + IVR
Hosted documentation AI

Available

An embeddable AI assistant for documentation sites, designed to add useful product-aware chat in a few minutes.

  • Drop-in widget
  • Sources + citations
Model research

Pretraining complete · SFT pending

A 1B-parameter multilingual language model pretrained from scratch on two RTX 4090s, with a custom tokenizer and data pipeline.

  • 1B parameters
  • 80,004 steps

02 / Field notes

The work behind the work.

All writing
3 min read

A blog should be a folder of files

A small publishing setup built around Markdown, static HTML, and conversations that happen elsewhere.

  • web
  • architecture
  • tooling

03 / Research notebook

Experiments. Evidence. Repeat.

Studio notebook

The full training logs, architecture decisions, and research postmortems live at Kroonen AI.

  1. 01Training logGenesis 1B: Run 2 Complete — 80,000 Steps
  2. 02ArchitectureNearly 3× Throughput on the Same Hardware
  3. 03PostmortemThe Optimizer State Bug: A Silent Failure in DCP Resume

How I build

Open where
it matters.

More about my approach
  1. 01

    Useful before impressive

    Start with a real constraint and ship the smallest system that solves it.

  2. 02

    Ownable by default

    Keep important data portable and the self-hosted tools telemetry-free.

  3. 03

    Publish the evidence

    Include costs, constraints, failures, and enough detail to reproduce the result.