Personal work, next to the consulting. Common thread: open source where possible, own hardware where necessary, and boring-but-auditable over clever.

Wordsworth — a sovereign PII pipeline

A document pipeline that turns government documents into a searchable, privacy-safe corpus: ingest → pseudonymisation → indexing → hybrid search and question-answering, all self-hosted (PostgreSQL, OpenSearch, a local LLM via Ollama, S3-compatible object store) — no document and no model call ever leaves the hardware.

Pseudonymisation is reversible with key-gated reveal: detection runs deterministically (Dutch BSN checksum, IBAN mod-97) plus ML entities, values are replaced by stable tokens, and only someone holding a valid grant and the cryptographic key can reveal, per PII type. The search index never contains clear personal data; the append-only audit table doubles as the pipeline’s state machine. Envelope encryption via OpenBao Transit; fail-closed on any doubt.

Boomhuis — and the pattern behind it

Boomhuis (“treehouse”) is the communication layer of my agent ecosystem: a self-hosted buzz relay (Nostr protocol) with channels where I and a handful of chat-native agents — builder, reviewer, architect, marketing — collaborate asynchronously. Every identity (human and agent) has its own keypair; everything is searchable and auditable; reachable only over my own tailnet. The repo is private (it holds identities), but the pattern is worth sharing.

The pattern: separate the layers, give each layer one job.

  1. Git is the truth. Code, verdicts, and audit trails live in git. Chat messages are coordination and mirror — never authoritative state.
  2. Execution lives in a cage. Agents that build code run as Kubernetes Jobs with deny-by-default allowlists per role (habitat, EUPL-1.2), with no access to the relay or to secrets. Communication and execution only meet through git.
  3. Knowledge has a hub. One repo (handbook) is the inventory and entry point; documentation aggregates there, not in every chat again.
  4. Identity is a keypair, not an account name. Agents are relay members with their own keys, roles, and channel permissions — adding, rotating, and revoking are ordinary, auditable operations.
  5. Soft advice, hard boundaries. What an agent should do lives in conventions; what an agent must not do is enforced at the runtime boundary. (Why that distinction matters: the shift-left session, in Dutch.)

No platform bought, no SaaS: a relay, a cluster, a few repos, and strict agreements. It doesn’t scale to a thousand people — it only has to scale to one human and a crew of agents.

netnl — measurable internet, in bulk

A command-line client for the Internet.nl batch API: test a whole fleet of domains for IPv6, DNSSEC, RPKI, and TLS instead of one domain per browser tab. Submit a host list, poll until the run finishes (resumable after a closed laptop), and get the result as a diffable table or JSON for pipelines. A GitHub Action ships with it, so your build fails the moment your score drops — a CI gate on your own standards compliance instead of a screenshot in an audit folder.

House rule: measure your own hosts freely, someone else’s only where the measurement is one their operator already invites — and then once, not in a loop.

The batch API needs an account, and that is where nearly everyone gives up. So there is now a full chain behind it: a self-hosted batch instance on a VPS, reached over a tailnet, with a facade in the homelab in front of it handling tenants, limits and an audit trail. Anyone who chips in for the electricity gets a key mailed automatically; the webhook mints it, sends it once, and stores it nowhere it could be read back.

It measures itself every morning, and the current standing is on the demo page — including the domain that comes off markedly worse. That number stays up on purpose: the domain is deliberately closed to the public, and a scoreboard showing nothing but green ticks measures nothing.

You can host it yourself, but it is a service, not a script. The four traps that cost me days are documented separately, including the one where the official manual leaves you with an instance that cannot reach anything.