mycelia

A conversation-first personal knowledge base.

Chat with an AI. A second AI automatically extracts what you said, organizes it, and writes it into an Obsidian-compatible markdown vault — with wikilinks, frontmatter, and folder structure intact.

Prototype release. This is an early version shared with the community. A polished desktop app with cloud sync is in development at mycelia.garden.

What it does

Most knowledge tools make organization the work. Mycelia inverts this. You have a conversation with an AI, and a second AI reads that conversation in the background — extracting notes, journal entries, and connections into a local markdown vault you own entirely.

The interface is a chat window. The output is a structured knowledge base that grows every time you talk.

• Automatic extraction — Facts, ideas, decisions, and people are extracted after every message exchange and written to the correct folder (topics/, people/, projects/, decisions/, ideas/). Existing notes are appended to rather than overwritten.
• Daily journal — Every session is summarized and appended to journals/YYYY-MM-DD.md with a timestamp.
• Knowledge graph — Live force-directed visualization of your vault's wikilink connections. Nodes are color-coded by folder. Phantom nodes appear for links not yet resolved.
• Note browser + editor — Browse your vault by folder, search by content (BM25 full-text), and edit notes with a WYSIWYG markdown editor (Tiptap).
• Backlinks — Every note shows all other notes that link to it.
• RAG retrieval — Ask "what did I decide about X?" or "remind me of my notes on Y" and Mycelia loads your vault as context.
• Obsidian-compatible — All output is plain markdown with YAML frontmatter and [[wikilinks]]. Your vault works in Obsidian, iA Writer, or any markdown tool — with or without Mycelia.
• Local-first — Your vault is a folder on your machine. No account required. Nothing leaves your device except direct API calls to Anthropic.

Screenshots

Stack

Getting started

Prerequisites

• Bun — package manager
• Rust — required by Tauri
• An Anthropic API key

Run in development

git clone https://github.com/your-username/mycelia
cd mycelia
bun install
bun tauri dev

On first launch, the onboarding wizard asks for your Anthropic API key and a vault directory. Both are stored locally.

Build

bun tauri build

Architecture

Data flow

1. User sends a message in chat.
2. If the message matches a retrieval pattern, the full vault is read and injected into the system prompt.
3. A streaming request goes directly to the Anthropic API.
4. Once the response completes, two background tasks run in parallel:
   • writeJournalEntry — summarizes the exchange and appends to today's journal.
   • extractKnowledge — extracts structured notes and writes them to the vault.
5. All output is plain markdown in the user-selected directory.

Vault structure

<vault>/
  journals/         — Daily entries (YYYY-MM-DD.md)
  topics/           — General knowledge and concepts
  people/           — People mentioned in conversation
  projects/         — Active projects and ventures
  decisions/        — Decisions with reasoning
  ideas/            — Raw ideas and creative sparks
  .mycelia/
    chat.json       — Persisted conversation history

Source layout

src/lib/ai/         — Claude client, extraction engine, RAG
src/lib/vault/      — Filesystem ops, graph builder, journal writer, markdown parser
src/lib/stores/     — Svelte stores (chat, settings, notes)
src/lib/search/     — BM25 full-text search index
src/lib/components/ — UI components
src/routes/         — SvelteKit pages (chat, graph, notes, daily, settings)
src-tauri/src/      — Rust: Tauri plugin registration only

Configuration

All settings are stored locally and never leave the machine (except the API key, which goes only to Anthropic).

Prototype status

This is a working prototype. Core features function but expect rough edges:

• Full-text search is implemented but not yet wired to the search UI
• No multi-conversation support (single thread only)
• No local model / Ollama support yet
• No auto-update

The commercial version under development adds a polished UX, Ollama integration, cloud sync, multi-device access, and an MCP server so Claude.ai Desktop can access your vault natively.

License

PolyForm Noncommercial 1.0.0 — free to use, modify, and study for personal non-commercial purposes. See LICENSE for full terms.

Contributing

Issues and discussion are welcome. Pull requests may be accepted for bug fixes.

For commercial licensing or to follow the product roadmap, visit mycelia.garden.