Building a Second Brain for My Health

Blog post #28

A stylized brain connected to a health knowledge graph with raw notes, wiki nodes, routines, and visits.

Today I shipped my first Claude Code skill. It’s a skill for writing these blog posts. And I’m using it right now, which feels very meta.

Skills are something I’ve been slow to adopt — not because I didn’t see the value, but because they never quite fit my workflow before. Today they did.

What shipped

  • A Claude Code skill for generating build-in-public log posts
  • A personal health wiki system built on Obsidian + Claude + GitHub
  • First entries: my dentist visit today, and two sets of routines for my daughter from her ophthalmologist and physiotherapist

What’s working

The idea that finally clicked for me: why does nobody follow the advice they get from physiotherapists?

I’ve been guilty of it myself. You get the exercises, you do them for a week, and then life happens. A few reasons I’ve noticed:

  • You don’t remember the exercises clearly
  • It’s hard to build new habits from scratch
  • When the pain goes away, so does the motivation

That’s the core problem I’m trying to solve with this system.

I’ve been following the discourse around Second Brain and Andrej Karpathy’s blog post on personal health RAG for a while. What I built today is my version of that — a knowledge graph where Claude compiles raw notes from appointments and health events into a structured, searchable wiki.

The flow: I dictate what happened at a visit (in plain Swedish, typos and all), Claude turns it into a structured raw file, compiles it into the wiki, and pushes to GitHub. I don’t touch the formatting or structure.

This also connects to my earlier work building knowledge graphs professionally — that work was what got me interested in LLMs in the first place. Now I’m applying the same thinking to myself.

Decisions made

  • Raw files are sacred — Claude never edits them, only reads them
  • Wiki is fully Claude-managed — I never edit it manually
  • The system covers both my health and my children’s health (routines from specialists, exercises, daily habits)
  • Long-term goal: everything from DNA to daily routines and bad habits in one graph — filled in gradually, with small apps built on top over time

Tooling & process

  • Obsidian as the reading/writing interface (just a local markdown folder)
  • Claude Code does all the compiling and structuring
  • GitHub private repo as backup and sync
  • Claude Code skill for blog posts — so I can just talk and it handles the rest

— Stefan