v0.5 · public beta · MIT-licensed core

Your AI agent.
On your laptop.
With teeth.

A self-hosted agent platform. Single Go binary. Multi-LLM (Claude, GPT, Ollama). Encrypted local vault for credentials. Sandboxed skills. Hash-chained audit log. Scheduled tasks. Native Mac menu-bar app. No cloud, no telemetry, no accounts.

Install Fathom Star on GitHub

Install in 60 seconds

Two ways. Both write to your machine and nowhere else.

Recommended

Homebrew

# macOS / Linuxbrew
$ brew install darklake-ai/fathom/fathom
$ fathom init --global
$ fathom

Updates ride your normal brew upgrade.

One-liner

curl

# macOS / Linux
$ curl -fsSL https://fathom.darklake.ai/install.sh | sh
$ fathom init --global
$ fathom

Downloads the matching binary into ~/.local/bin/.

What's in the box

Every box is real code, in the repo, today.

One binary, three runtimes

Claude, OpenAI, Ollama. The agent loop is provider-agnostic — switch in one line. Run Ollama for offline; switch to Claude for the heavy lift; never refactor a tool call.

Encrypted local vault

Credentials live in an encrypted file unlocked by your OS keychain or a passphrase. The egress proxy injects them into outgoing requests at proxy-time — skills never see the raw token.

Hash-chained audit log

Every tool call, every LLM round-trip, every policy decision — written to an append-only log where each entry hashes the previous one. Tamper with one row, the chain breaks visibly.

Scheduled tasks

Cron-style recurring agent runs. "Every weekday at 9am, summarize my unread GitHub notifications and DM me the rollup." Persisted across reboots; delivered through any wired channel.

Sandboxed skills

Gmail, Calendar, GitHub, Slack, Discord, WhatsApp, Telegram. Each runs in its own subprocess with declared capabilities and scoped vault access. Add your own — it's a manifest plus a TypeScript file.

Native Mac menu-bar app

Click the iceberg. Chat with your agent. Dictation via on-device Speech. ⌘⇧Space from anywhere. Auto-update via Sparkle. Zero external dependencies — ~600 lines of Swift.

Native

A Mac app, not a web wrapper.

~600 lines of Swift. AppKit + SwiftUI + system frameworks only — no Electron, no React Native, no Catalyst. Lives in your menu bar where you already are.

  • Click the iceberg, chat with your agent
  • ⌘⇧Space global hotkey from any app
  • On-device speech dictation (no audio leaves your machine)
  • Native notifications for scheduled tasks
  • Sparkle auto-update once signed builds ship
  • Auto-start at login via SMAppService
Build from source Signed .dmg coming with v0.6
Finder ⏻ 🔍 Fathom 9:41
Fathom claude-opus-4
summarize the prs i was tagged in this week
You were tagged in 4 PRs this week. 3 are blocked on your review — the auth-middleware rewrite (#1142), the migration runner refactor (#1156), and the OIDC SSO patch (#1163). The fourth (#1170, docs) is ready to merge.
›

One binary. Three setups.

Fork it for yourself. Layer in team features when you need them. Same code, same install.

Personal

Just you.

Free · MIT

A chat brain that runs on your laptop and talks to your phone. The default install.

  • Agent loop, local vault, encrypted secrets
  • Sandboxed skills (Gmail, GitHub, Slack, more)
  • Mac menubar app + mobile PWA + CLI
  • Hash-chained audit log + scheduled tasks
  • Cross-device thread sync over Tailscale or Cloudflare Tunnel
fathom init
Use fathom init --minimal for the lean chat-brain build — skips scheduler, threads, audit log. Boots in ~150ms.
Team

Your small business.

Free · MIT

Everything in Personal, plus multi-user. Same binary — flip a flag.

  • Multi-user accounts with isolated workspaces
  • Tenant model — separate vaults, separate threads
  • Role-based access control (admin / member / viewer)
  • Per-user audit trails, queryable from the admin API
  • Shared skills, shared scheduled tasks across the team
fathom init --team
Bring your own auth method (token, passkey, or OIDC). No vendor account, no per-seat pricing.
Enterprise

The whole company.

Open core · commercial available

Team features plus the compliance surface auditors actually ask for.

  • SSO via OIDC (Okta, Azure AD, Google Workspace, custom)
  • SCIM provisioning + group sync
  • Compliance reports — SOC 2, HIPAA, GDPR — generated from the audit log
  • Admin API for tenant + RBAC + policy automation
  • Bolt-ons: external egress (Charon), container sandbox (Chasm), OTLP telemetry (Beacon)
fathom init --enterprise
Open-source under the same license. Talk to us if you want managed deployment, SLAs, or a private support channel.

Switch modes by editing one line in fathom.config.yaml and restarting — no migrations, no separate downloads.

Run an agent that's actually yours.

Open source. Local-first. No accounts. No telemetry. No vendor lock-in.

Install Fathom View source