Scenarios

The prices below are Hetzner’s, read from its API on 23 October 2026 for Nuremberg, including 19 % VAT. Hetzner bills them to your account. Vaicoa itself costs nothing. Not included: public IPv4 addresses (€0.60 a month each), the Object Storage bucket and traffic.

The smallest set-up

One hub, one production server, one staging server, and one coding agent working on one twin.

The smallest set-up. Four servers in two projects. You and the agent talk only to the hub; the hosts and the twin connect out to it. The agent reaches the twin through the hub's twin proxy, and production only by asking you.

server	project	made by	type (default)	per month
the hub	the hub’s	vai up	cpx02 (1 vCPU, 1 GB)	€7.13
web-1, production	the hub’s	vai host create	cpx22 (2 vCPU, 4 GB)	€23.19
web-2, staging	the hub’s	vai host create	cpx22	€23.19
task-42, a twin of web-1	the twins’	the agent, vai twin create	cpx22	€0.037 an hour

The commands: vai host create web-1 --env production, vai host create web-2 --env staging, and the agent’s vai --agent claude-code twin create --production web-1 --task task-42.

Servers that run all month: €53.51. A twin runs for its time to live, 4 hours by default, about €0.15, and is deleted after it.

What talks to what:

• You reach the hub through vai’s WireGuard tunnel with your device key. You are the owner.
• The coding agent uses vai --agent claude-code with its own agent key. It may create, reset and delete twins and open them; a delete or a release promotion on web-1 or web-2 waits for your approval. See agents and approvals.
• web-1 and web-2 each run vaicoa-agent and your environment under Podman. They send signed requests to the hub over the private network.
• The twin runs your environment from a branch the agent names, with seed data. It holds a tunnel out to the hub and opens no port.
• Staging is why the set-up has two hosts: when a staging server or a twin exists, production waits until one of them has run a release. See releases and updates.

A step up: two environments, several twins

The same hub with two environments, shop and api, each with a production and a staging host, and three twins running at once.

servers	project	type	per month
the hub	the hub’s	cpx02	€7.13
2 production hosts, 2 staging hosts	the hub’s	cpx22	4 × €23.19 = €92.77
3 twins at once	the twins’	cpx22	3 × €0.037 an hour

Servers that run all month: €99.90. Each host runs one environment; each twin is a copy of one of them. The hub still runs on its cpx02. A recovery test adds a throwaway server in the twins’ project for the length of the test, 64 to 75 s on Hetzner (20–21 October 2026).