Features

A coherent stack across every machine.

HarnessSync replaces the half-day of "set up the new laptop" with one click. The desktop app installs the right CLIs, MCP servers, and editor extensions. Your skills, prompts, and config follow you across machines.

Install

One desktop app, every harness.

Claude Code: Anthropic's official CLI, installed and updated alongside its MCP servers.
Codex CLI: OpenAI's codex CLI plus the toolchains it expects.
Cursor & Aider: Editor + agentic-CLI for those who prefer that workflow.
MCP servers: Filesystem, fetch, GitHub, Linear, Slack – opt in per project.
Portable git + gh: No system git surgery; downloaded lazily on first use.

Sync

Local-first, optional cloud.

Skills: Custom skills sync to every machine, identical and versioned.
Slash commands: Your /commands move with you, including project-specific ones.
Hooks: PreToolUse / PostToolUse hooks shared across all your machines.
Prompts & subagents: Long-form prompts, system prompts, and subagent definitions.
Settings.json: Permissions, env vars, and keybindings – same everywhere.

Cloud

Pro tier – managed, no GitHub needed.

HarnessSync-managed git: No "where do I put the repo?" – we host it. Your data, encrypted in transit.
Multi-device handoff: Open the laptop, everything's already there.
Storage that scales: 100 MB included; +€1/month per 250 MB block.
Quota awareness: Push pauses when you hit the cap. Pull and export keep working.

Account

Identity, billing, devices.

Email + OAuth: Email/password, Google, GitHub. Sanctum-backed sessions for the dashboard.
Per-device tokens: Each machine gets its own token; revoke from the dashboard.
Stripe billing: Cashier-managed subscriptions, EU VAT, invoicing – all standard.
Customer Portal: Cancel, update card, change plan, download invoices – one click.

How it works

Three boxes, two arrows.

Your machines push to a HarnessSync vault and pull from it. The vault is where your skills, prompts, hooks and MCP definitions live. Every CLI on every machine reads from the same place.

    ┌──────────────────────┐         ┌──────────────────────┐         ┌──────────────────────┐
    │  laptop / desktop    │         │  HarnessSync vault   │         │  laptop / desktop    │
    │                      │         │                      │         │                      │
    │  ~/.claude/          │  push   │   skills/            │  pull   │  ~/.claude/          │
    │  ~/.codex/           │ ──────▶ │   prompts/           │ ──────▶ │  ~/.codex/           │
    │  ~/.cursor/          │         │   hooks/             │         │  ~/.cursor/          │
    │  ~/.opencode/        │  pull   │   mcp/               │  push   │  ~/.opencode/        │
    │  ~/.gemini/          │ ◀────── │   settings.json      │ ◀────── │  ~/.gemini/          │
    └──────────────────────┘         └──────────────────────┘         └──────────────────────┘
              ▲                                  │                                ▲
              │                                  │                                │
              └────────── encrypted in transit ──┴────────── revocable per device ┘

Local-first. Push when you change something. Pull when you want what changed elsewhere. The cloud tier means we host the vault for you – otherwise bring your own git remote.

Comparison

Why not just git?

You can. People do. We did, for a year. Here’s where it stops being free.

	HarnessSync	Raw git / dotfiles	Mackup / chezmoi	Manual sync
Sync across machines	●	●	●	●
Per-CLI awareness	●	○	○	○
Skills + hooks + MCP	●	○	○	○
Conflict resolution	●	◐	○	○
Revoke a single device	●	○	○	○
No git knowledge required	●	○	●	○
Storage included	●	○	●	○
Encrypted at rest	●	◐	●	◐
Works without your repo being public	●	●	●	●
Designed for AI tooling	●	○	○	○

● yes ◐ partial · needs setup ○ no

Ready to try it?

Create free account → See pricing