A machine you can check, not one you have to trust
Cloudflare Sandbox
One container per purchase, started with the internet switched off and only the hosts your policy allows routed in. One vCPU, 4 GiB of memory, 20 GB of disk, running around the clock so a web session or a scheduled agent always has a machine.
Nix, reproducible
The image is built from a pinned flake. Belai and the Vulnetix CLI are fetched by checksum, every package comes from the pinned nixpkgs, the build is checked twice for the same hash, and the SBOM is published. On boot the machine re-hashes its binaries against the pins before Belai starts.
Jev, free
Belai's security classifier runs on every tool call and prompt. On a sandbox it costs nothing: the machine holds a placeholder, and the real key is swapped in at the network edge for calls to the Jev API alone. A leaked environment is worth nothing.
Egress you can see
Every hostname the machine reaches is recorded with how often and how often it was refused, each with an Allow or Deny. Choose to log everything, or to deny everything except the hosts you allow. The sync, firewall and Jev hosts are always reachable.
From purchase to a running host in one launch
- Buy and name it. One subscription per sandbox from the console. The machine is created as soon as the payment is confirmed.
- Choose repositories. Public GitHub repositories, or private ones through the Vulnetix GitHub App. Each is checked for access, listed by branch and sized against the disk before it can be added.
- Pick packs and extensions. Python, Node, Go, Rust, Java and more, plus any nixpkgs attribute, installed from the signed cache. The first launch estimates their size; later ones use what was measured.
- Launch. The image is verified, the firewalls are configured, the repositories are cloned, and belai rc starts with exactly those directories trusted. Relaunch replaces the machine from a fresh disk whenever you change the configuration.
- Work from the console. Start sessions, install agents and crews, and sync provider keys from the Belai pages you already use. The sandbox is a host like any other.
What the machine holds, said plainly
The sandbox signs in to Vulnetix with your organisation's Belai credential, the same one any belai rc host uses, so it can sync sessions, take requests from the console and fetch provider keys into the firewall vault. Clones of your repositories live on its ephemeral disk and are re-cloned from GitHub on every relaunch, so uncommitted work on the machine does not survive a relaunch. Belai's own guardrails stay on; a sandbox cannot turn them off.
What it cannot do
- No shell, no SSH and no exposed ports: the console is the only way in.
- No model key is stored in the machine: provider keys arrive through the Belai sync and go to the Vulnetix AI Firewall vault.
- Nothing is built from source on the machine: packages install only from the signed cache.
- The machine never trusts a parent directory: each repository is its own trusted root.
110 US dollars per sandbox, per month. Jev at no charge.
The price is our Cloudflare cost for an always-on instance of 1 vCPU, 4 GiB and 20 GB, plus a fixed margin, rounded to the nearest ten dollars. Buy as many as you need; each is its own subscription you can cancel at the end of any period.
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What is a Pix Sandbox?
A Belai machine Vulnetix runs for you around the clock on a Cloudflare Sandbox container, for one monthly price per machine. You choose the GitHub repositories it clones, the language packs it installs from a pinned Nix image, and which hosts it may reach. You work from the Belai console; you never connect to the machine.
Why is Jev free on a sandbox?
Jev is the decision model Belai uses as its security classifier on every tool call and prompt. On a Pix Sandbox the machine holds only a placeholder and the real key is swapped in at the network edge for calls to the Jev API alone, so the key never enters the container and we can include it at no charge.
How is the image verified?
The image is built from a pinned Nix flake. Belai and the Vulnetix CLI are fetched by checksum, every package comes from the pinned nixpkgs, the build is repeated to confirm the same hash, and the SBOM is published. On every boot the machine re-hashes its binaries against the pins before Belai starts, and the console shows the result.
What does the price cover?
Our Cloudflare cost for an always-on instance of 1 vCPU, 4 GiB of memory and 20 GB of disk, plus a fixed margin, rounded to the nearest ten dollars: 110 US dollars per sandbox per month. Each sandbox is its own subscription you can cancel at the end of any period.