Ambit CLI

What Ambit Is

Ambit deploys apps to the cloud in a way that makes them completely unreachable from the public internet. Only devices enrolled in the user's private Tailscale network can connect to them. From the outside world's perspective, the app does not exist — there is no IP address to find, no port to scan.

This matters because putting a database, dashboard, or internal tool on the normal internet forces you to build login pages, configure firewalls, and harden the app against strangers. Ambit skips all of that. Access control is handled at the network level: if a device is on the Tailscale network, it can reach the app; if it isn't, the connection is refused before the app ever sees it.

Each private network you create is called an ambit. Every app deployed to it gets a human-readable address under that network's name — so http://my-app.lab means the my-app application on the lab ambit. These addresses work automatically for any device enrolled in the user's Tailscale account.

Installation

If ambit is not already installed, run it directly via Nix:

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How It Works

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Ambit creates a router on Fly.io that joins the user's Tailscale network and advertises the private IPv6 subnet for that ambit. It also sets up split DNS so that *.<network> queries resolve to the right app. Apps deployed with ambit deploy get a private Flycast address on the network and never receive a public IP.

Prerequisites

• - flyctl installed and authenticated (fly auth login)
• Tailscale installed and connected (tailscale up)
• Accept-routes enabled (sudo tailscale set --accept-routes)
• A Tailscale API access token (tskey-api-...) — create one at https://login.tailscale.com/admin/settings/keys

Commands

ambit create <network>

Creates a new private network. This is the first command to run when setting up a new ambit. It deploys a router on Fly.io, connects it to the user's Tailscale network, and configures split DNS so apps on the network are reachable by name.

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Flags:

• - --org <org> — Fly.io organization slug
• INLINECODE13 — Fly.io region (default: iad)
• INLINECODE15 — Tailscale API access token (prompted interactively if omitted)
• INLINECODE16 — Tailscale ACL tag for the router (default: tag:ambit-<network>)
• INLINECODE18 — Approve subnet routes via Tailscale API instead of requiring autoApprovers in the ACL policy
• INLINECODE19 — Skip confirmation prompts
• INLINECODE20 — Output as JSON

What it does:

1. 1. Validates Fly.io auth and the Tailscale API key
2. Checks that the tag (default tag:ambit-<network>, or custom via --tag) exists in Tailscale ACL tagOwners
3. Checks autoApprovers config (unless --self-approve)
4. Creates a Fly.io app on the custom network
5. Sets secrets: TAILSCALE_API_TOKEN, NETWORK_NAME, INLINECODE26
6. Deploys the router container
7. Waits for the device to join the tailnet
8. Configures split DNS (*.<network> → router)
9. Enables accept-routes locally if possible

Before running, the user must add the router's tag in their Tailscale ACL settings at https://login.tailscale.com/admin/acls/visual/tags. The tag defaults to tag:ambit-<network> but can be overridden with --tag.

And optionally (or use --self-approve to skip this):
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ambit deploy <app> --network <name>

Deploys an app onto a private network. This is the safe alternative to fly deploy: it always passes --no-public-ips and --flycast, runs pre-flight checks on the fly.toml for dangerous settings, and audits the result to verify no public IPs were allocated.

There are three mutually exclusive deployment modes:

Config mode (default) — uses a local fly.toml:
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Image mode — deploys a Docker image without fly.toml:
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Template mode — fetches a template from a GitHub repository and deploys it:
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Flags:

• - --network <name> — Target network (required)
• INLINECODE37 — Fly.io organization
• INLINECODE38 — Primary region
• INLINECODE39 — Explicit path to fly.toml (config mode)
• INLINECODE40 — Docker image to deploy (image mode)
• INLINECODE41 — Internal port for HTTP service in image mode (default: 80, "none" to skip)
• INLINECODE42 — GitHub template reference (template mode)
• INLINECODE43 — Skip confirmation
• INLINECODE44 — Output as JSON

Template reference format:
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The template must contain a fly.toml (and typically a Dockerfile). The template is fetched from GitHub's tarball API, the target subdirectory is extracted, pre-flight scanned, and deployed. The temp directory is cleaned up automatically.

ambit list

Lists all discovered routers across all networks.

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Shows: network name, app name, region, machine state, private IP, subnet, and Tailscale device status.

ambit status

Shows detailed router status. Run without --network to see all routers, or with --network to focus on one.

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Detailed view includes: machine state, SOCKS5 proxy address, Tailscale IP, online status, advertised routes, and split DNS config.

ambit destroy --network <name>

Tears down a router and cleans up all associated resources. Apps deployed on the network are NOT deleted — only the router is removed. The user will need to manually remove ACL policy entries for the network tag.

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What it does:

1. 1. Finds the router app for the network
2. Clears split DNS configuration
3. Removes the Tailscale device
4. Destroys the Fly.io app

ambit doctor

Health check for the local environment and router infrastructure. Run this whenever something seems wrong — it checks the most common failure points and gives remediation hints.

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Checks:

• - Tailscale CLI installed
• Tailscale connected (BackendState = Running)
• Accept-routes enabled
• Router(s) exist and machines are running
• Router(s) visible in tailnet

Templates

Ready-to-deploy templates are available at ToxicPine/ambit-templates:

Template	Description
INLINECODE53	Headless Chrome exposing Chrome DevTools Protocol on port 9222 — for AI agents or scripts that need a browser on the private network.
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A cloud devshell with a web terminal, persistent home directory, passwordless sudo, and auto start/stop. |
| ToxicPine/ambit-templates/opencode | A private OpenCode web workspace — Nix-based environment with persistent home and auto start/stop. |

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Common Workflows

First-Time Setup

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Deploy from a Template

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Debugging Connectivity

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Tearing Down

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Troubleshooting

Symptom	Fix
"Tag not configured in tagOwners"	Add "tag:ambit-<network>": ["autogroup:admin"] to Tailscale ACL tagOwners.
"autoApprovers not configured"

Either configure autoApprovers in the ACL or re-run with --self-approve. | | Router deployed but not reachable | Run ambit doctor. Check that accept-routes is enabled locally. | | "Timeout waiting for device" | Check router logs. Most common cause: expired or invalid Tailscale API key. | | Apps not resolving as <app>.<network> | Verify split DNS is configured: ambit status --network <name>. Check the router is online in the tailnet. | | "Flyctl not found" | Install from https://fly.io/docs/flyctl/install/ |