A Second Brain That My AI and I Share

My AI assistant and I share the same brain. Not metaphorically, we literally read and write to the same knowledge base. When I update a project note in Emacs, Nabu (my AI) sees the change. When Nabu logs something it learned, I see it in my daily file. This post is about how it works.

How It Works#

Nabu connects to my self-hosted Matrix server and it has access to my org-roam knowledge base via an MCP server I built. But it’s not just access, it’s integration. Nabu treats org-roam as its source of truth:

Building a Mobile Interface for My Second Brain with n8n and Matrix

My org-roam knowledge base is the center of how I think and work. But it lives in Emacs, which means I can only capture ideas when I’m at my computer. I wanted a way to feed my second brain from anywhere, using just my phone—but I refused to put my notes in someone else’s cloud. The solution had to be entirely self-hosted. What I built combines Matrix for messaging, n8n for orchestration, and an MCP server that bridges to org-roam, all running on my own infrastructure.