It's not you. It's me.
I've had a private brain repository for years now. The main branch is cerebellum. Hundreds of commits, a single contributor. An audience of exactly me.
However, it was never about the repository, it was about the idea it represented.
For years, that repository was where everything went. Not only the important things, but the interesting ones: hacks, code snippets, ideas, proofs of concept, a very long library of scripts... All of it landed there with the same commit message: synchronizing local with remote at <unix timestamp>. Turns out I've been trying to sync my brain with a remote for years, one Unix timestamp at a time.
Here's the thing nobody told me about this repository: it's a write-only medium (chmod 200). Information went in, nothing came back out. Search was grep-based, so retrieval was luck, and all the information in it quietly aged (four years ago, three years ago...).
I know I could just tell Claude, "Hey Claude, read this repository and look for <insert query>", but something about that always felt off. Time changes everything, technology included, and that felt like a workaround, not a way of working. I felt that my brain repository deserved better.
A couple of months after Iñaki, Josemi, and I started building Arche, I set up my personal instance. I could see the potential from day one, but I never got the time or the patience to set it up for myself. But two months ago, I felt the world was moving at a pace I couldn't keep up with: there are so many exciting things to learn, so much to build, so much to understand, that I'm not joking when I say there aren't enough hours in the day to do everything I want to do and study everything that I want to study.
So here I am, after two months of fine-tuning my agents' system prompts, skills, and Knowledge Base, writing a farewell letter to my long-loved brain repository.
I didn't delete brain. That felt too much like a funeral, and this isn't one.
The first thing I did on my instance was point the GitHub connector at the repository and let it read the whole thing: every folder, every timestamped commit, years of notes to nobody. For the first time, something other than me read all of it, and the void got an audience. brain got restructured, dusted off, and turned into a living Knowledge Base.
That's the whole letter, really. The write-only medium finally has a reader.
Everything else grew out of that. The MCP server wires my local coding agents straight into the Knowledge Base, so they show up already knowing what I know. No more introducing my own projects to a model that's meeting them for the first time, every single time. Flows keep watch on the repositories I care about and surface the issues, bugs, and releases I used to find out about three days late from someone else's timeline. And when I actually want to muse, I open a session and dig: pull a thread, chase it down, come out the other side with the conclusion written somewhere that isn't my hippocampus.
We never built Arche for any of this, by the way. It's meant to sit quietly under a company's work: processes, agents, the glue between tools. It just turned out that a second brain for a company and a second brain for a person are closer than we thought.
The small things are the ones that got me. Vega-Lite rendering right in my markdown reports, so an experiment becomes a chart without leaving the page. Proactive memory quietly catching what I'd otherwise have lost to the timestamp graveyard. Little upgrades to a thing I'd long stopped expecting to improve.
The remembering is handled. Thanks for holding all of it for so long.
Last manual commit to cerebellum was last month. It won't be the last, but the job has changed.
Goodbye, brain. You've been promoted.