Tech
The engine room
For those who want the details. No hostnames, no ports — principles and tools.
- Notebook: Obsidian — Markdown files in folders, linked like a network
- Rules: one context file per folder (AGENTS.md) the AI reads before working
- Agent: Claude (Anthropic) through an Obsidian integration; procedures are documented model-independently
- Home server: virtualisation with one container per service, document archive with OCR (paperless-ngx), own Git (Forgejo), smart-home hub
- Backup: local snapshots, encrypted off-site copy, cold copy; restores are rehearsed
- Tools: over a hundred small scripts in Python and Node — each does one thing, deterministically, with tests
- This page: statically built (Astro), content generated from the notebook, numbers with their counting command, no cookies, no external services
Counted when this page was built
| 2,035 | notes in the network nodes in the notebook's link graph |
| 15,200 | links between notes edges in the link graph |
| 66 | context files (one per folder) number of AGENTS.md files below the root |
| 52 | documented procedures entries in the procedure register |
| 104 | own tools directories in the tool repository |
| 5,129 | versions of the notebook git rev-list --count |
The five questions I get asked
- Where is the data?
- With me. Text files on my own server, versioned, backed up three times. Only my copy is permanent; how long the vendor retains anything is governed by its terms.
- What if the vendor is gone tomorrow?
- Rules and knowledge live in Markdown and Git, not in the model. Another model reads the same notes.
- What breaks if I drop out?
- Procedures, pitfalls and the emergency folder are documented; the system has gone out to others as a template.
- What does it cost?
- 2026: around €550 for the model subscription and around €160 for the off-site copy; hardware once.
- Does it scale to 10,000 employees?
- Proven for a unit of around 300 people. The pattern itself does not depend on size: context as files, a deterministic core, a human who decides.
What it can't do
- It decides nothing irreversible. Deleting, sending, paying stay with me, on purpose.
- It rarely measures time saved. Most numbers on this page are quantities and effects, not hours. Where I estimate, a ≈ marks it.
- It isn't free: model subscription, electricity, hardware, and my evenings.
- It gets worse the moment I stop turning mistakes into rules.
It built this page. I reviewed and signed off.