Burrow

A free, open-source mole.fit — a native macOS GUI for the Mole CLI (mo).

Burrow wraps the free, open-source mo CLI in a native Mac app: clean
junk, manage & uninstall apps, run safe maintenance, map your disk, and
watch live system status — five tools in one window. On top of that it
adds two things the CLI doesn't have: a long-running history of your
Mac's metrics in a local SQLite database, and an MCP server so Claude
Code can ask "what's been happening on this Mac."

Burrow is an independent open-source project. It's inspired by
mole.fit's structure and built on the same mo engine, but it is not
affiliated with or endorsed by mole.fit — its own name, mark, palette,
and copy are original.

Screenshots

The five tools

Plus, Burrow's own extras

• Menu-bar HUD — health hero, metric tiles, top processes, and live
  status of any job running in the app, from the menu bar.
• History — long-range charts (5 m → 90 d) over a local SQLite history
  of every metric, plus peak-per-process tables.
• MCP server — both a localhost HTTP API and a stdio JSON-RPC server
  (Burrow --mcp) so Claude Code can query your Mac's recent state.

How Burrow compares

Honest notes: mole.fit is more polished, signed, and supported — buy it
($9) if you want that and to fund mo. Pearcleaner is an excellent,
focused open-source uninstaller. ncdu/mo are terminal tools; Burrow is
the GUI for people who'd rather not live in the shell.

Requirements

• macOS 14+
• The Mole CLI — brew install mole. Hard requirement; Burrow refuses
  to launch without mo on PATH.

Install

Burrow is unsigned for now (pre-1.0). Each path below clears the
Gatekeeper quarantine for you. The honest security/trust details — network,
admin rights, no telemetry — are in SECURITY.md.

Homebrew (recommended)

brew install mole                        # required engine
brew install --cask caezium/tap/burrow   # the app (clears quarantine)

Direct download

Download Burrow-x.y.z.zip from
Releases, unzip into
/Applications, then:

xattr -cr /Applications/Burrow.app
open /Applications/Burrow.app

Build from source

brew install xcodegen mole
git clone https://github.com/caezium/Burrow.git && cd Burrow
xcodegen generate
xcodebuild -project Burrow.xcodeproj -scheme Burrow \
  -configuration Release -destination 'generic/platform=macOS' \
  -derivedDataPath build \
  CODE_SIGN_IDENTITY="" CODE_SIGNING_REQUIRED=NO CODE_SIGNING_ALLOWED=NO build
cp -R build/Build/Products/Release/Burrow.app /Applications/
xattr -cr /Applications/Burrow.app
open /Applications/Burrow.app

Burrow lives in the menu bar (it's a menu-bar agent). Click the icon →
Open Burrow.

Security & trust

Burrow drives the audited mo CLI and adds no surveillance of its own:

• No telemetry, analytics, accounts, ads, or third-party SDKs, and no
  backend — nothing to phone home to.
• No background root helper. When Clean/Optimize need admin rights,
  macOS's own dialog asks you and Burrow runs that one mo command, then
  exits — you approve every elevation.
• Local-only: the MCP HTTP server is loopback (127.0.0.1, toggle off
  in Settings); history is a local SQLite file. The one opt-in network call
  is brew outdated in the Updates tab.
• Unsigned, pre-1.0 — full honest write-up, including the trade-offs of
  the admin path, in SECURITY.md.

Wire it into Claude Code

Burrow doubles as an MCP server. Add to ~/.claude/settings.json:

{
  "mcpServers": {
    "burrow": {
      "command": "/Applications/Burrow.app/Contents/MacOS/Burrow",
      "args": ["--mcp"]
    }
  }
}

Restart Claude Code. Tools: burrow_snapshot, burrow_history,
burrow_top_processes, burrow_info. There's also a localhost HTTP API
on 127.0.0.1:9277 (/health, /info, /snapshot, /metrics).

Develop & test

xcodegen generate
xcodebuild -project Burrow.xcodeproj -scheme Burrow \
  -configuration Debug -destination 'platform=macOS' test

38 tests: DB roundtrip + range + stride sampler + prune (10), Store
clamping + defaults (9), Maintenance prune (3), MCP tool routing (7),
squarified treemap invariants (9).

Architecture

mo status --json   ──>  Sampler ──> SQLite (WAL) ──┬─> Status / History (charts)
                                                   ├─> HTTP QueryServer (:9277)
                                                   └─> Burrow --mcp (stdio) ─> Claude Code
mo analyze --json  ──>  DiskScanner + squarified Treemap ──> Analyze
mo clean / optimize ─>  CommandRunner (streamed) ──────────> Clean / Optimize
mo uninstall --list ─>  Software (+ brew outdated for Updates)

One binary, two modes: default is the menu-bar GUI; Burrow --mcp is the
stdio MCP server (it forks before SwiftUI claims the process). The whole
UI is one translucent window with a top-pill nav (Brand/Tool design
system); Settings and History are panes in that same window.

Attribution & license

MIT.

• Mole CLI (mo) is © tw93, MIT.
  Burrow depends on it at runtime and bundles nothing from it.
• Inspired by the mole.fit Mac app (same author as mo). Burrow is an
  independent reimplementation with its own brand — no assets, icons,
  copy, or trade dress are taken from mole.fit.
• The history-DB + MCP pattern shares lineage with the same author's
  Stats fork (caezium/stats@henry/history-mcp).
• Treemap layout: Bruls, Huijsen & van Wijk (2000), "Squarified Treemaps,"
  re-implemented from scratch in Swift.