FermiVault

Fast, local-first Markdown notes that your AI apps can work with natively.

• Plain files. A vault is any folder of .md files. Nothing proprietary; app state lives in /.fermi/: the index and snapshots there can be rebuilt; settings and plugins live there too.
• Fast. Rust core + native webview (Tauri 2), SQLite FTS5 search, incremental indexing off the UI thread.
• AI-native. A built-in MCP server lets Claude Desktop, Claude Code, Codex, Cursor, VS Code, Windsurf, Gemini CLI and LM Studio search, read and edit your vault. Connect any of them with one click from the AI apps panel. Every agent edit is snapshotted so it can be undone.

Download

Get the latest Windows installer from Releases: download FermiVault_x.y.z_x64-setup.exe and run it. No admin rights are needed; it installs for your user and adds a Start menu entry. Then pick any folder as your vault.

The installer isn’t code-signed yet, so Windows SmartScreen may say “Windows protected your PC”. Choose More info → Run anyway. macOS and Linux builds will follow; until then, build from source (below).

Features

• Live-preview Markdown editor (CodeMirror 6) with source mode, [[wikilinks]] + autocomplete, formatting shortcuts, code highlighting
• Callouts (> [!tip]), task checkboxes (Ctrl+L), KaTeX math ($…$, $$…$$), Mermaid diagrams
• Embeds: ![[image.png|300]], ![[note]], ![[note#Section]] (transclusion), PDFs, audio and video
• Graph view (global, Alt+G, and per-note local graph), tags pane, backlinks, outline
• Daily notes (Ctrl+Shift+D), templates with {{title}}/{{date}}/{{time}} (Ctrl+Shift+T), bookmarks
• File recovery: automatic snapshots (every 5 minutes while editing, before every AI-agent change), restore any version
• Vim key bindings (Settings, or “Toggle Vim key bindings”), loaded only when turned on
• Tabs and split panes, quick switcher (Ctrl+O), command palette (Ctrl+P), full-text search
• Link-safe rename/move (every [[link]] and [x](note.md) is rewritten)
• Properties (YAML frontmatter) edited in the right panel, with text, list, date and checkbox fields
• Tables of notes: a ```table block lists notes by tag or folder, filtered and sorted by their properties, live (see Project board in fixtures/test-vault)
• Canvas: infinite boards of text cards, notes, images, links and groups with arrows, stored as open JSON Canvas .canvas files (see Planning board in fixtures/test-vault)
• Web clipper: Clip web page as a note saves a page’s article as Markdown (using defuddle) with its title, author, date and source as properties, in a Clippings folder you can change in Settings
• Git sync (Settings → Sync): version history and sync through any Git host, by hand or every 5/15/60 minutes, using your installed git. If a note changed on both sides, your version stays and the other is saved next to it as a (conflict …) copy
• Plugins: add commands and automate your vault in JavaScript. Each plugin runs in a sandboxed worker with no network access and only the permissions you approve (see docs/PLUGINS.md)
• Interface in English, Español, Français and Deutsch (Settings → Language; follows the system by default). Adding a language is one JSON file: see docs/TRANSLATING.md
• Image, PDF, audio and video viewers; file tree with drag-and-drop; trash instead of delete; light/dark themes
• Live reload when files change on disk (external editors, sync tools, agents)

Heavy renderers (KaTeX, Mermaid, the graph) load only when a note first needs them, so they never slow startup.

AI inside the app

• Semantic + hybrid search. Search ranks notes by keywords (BM25) and meaning together. Meaning comes from a local Model2Vec model (potion-base-8M, ~30 MB, CPU-only, downloaded once from Settings → AI). Indexing runs in the background and re-embeds only paragraphs that changed.
• Chat with your notes (Ctrl+J). Answers are grounded in the most relevant passages and cite them; citations link to the source note.
• Inline writing commands: improve writing, fix spelling and grammar, summarize, continue writing (Ctrl+Shift+Enter). Results stream into the editor and undo with Ctrl+Z.
• Related notes with one-click linking, in the Backlinks panel.
• Any model. Chat and writing use any OpenAI-compatible server. Ollama, LM Studio and llama.cpp are detected automatically on localhost; hosted APIs work with a key stored in the OS keychain.

AI apps connected over MCP get the same hybrid search plus a related tool.

Tables

```table
from: #project, work/        (tags and/or folders; leave out for all notes)
where: status != done        (one condition per line: = !=  >= contains exists missing)
where: due < 2026-12-01
sort: due desc
columns: file, status, due
limit: 50
```

Fields are any property plus file, path, folder, modified and tags. Numbers compare as numbers, everything else as text, so ISO dates sort correctly. Agents use the same syntax through the MCP query tool.

MCP tools

search, read_note (whole note or one section), list_notes, recent_changes, links, related, query (notes by properties and tags, as a table), tags, create_note, edit_note (append / str_replace / replace_section / replace), rename_note.

Run it manually:

fermivault mcp --vault /path/to/vault

Privacy

• Your vault never leaves your computer unless you send it somewhere: chat and writing go only to the model server you pick in Settings → AI. Plain http is allowed only on your computer or local network, and API keys are only sent over https (or to your own computer).
• Images from the web in notes and AI answers wait for a click, so opening a note never contacts another server. Turn on Load web images automatically in Settings if you prefer.
• The semantic search model is downloaded once, on request, from a pinned Hugging Face revision and checked against its SHA-256.
• Security issues: see SECURITY.md.

Develop

Requirements: Rust (stable), Node 20+, pnpm, and the Tauri prerequisites.

pnpm install
pnpm tauri dev

cargo test --manifest-path src-tauri/Cargo.toml
pnpm test

fixtures/test-vault is a small vault for trying things out.

License

MIT