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Krova CloudKrova Cloud
Multi-tenant platforms

Run user & untrusted code

Give every end-user their own isolated Cube. Each one is a Firecracker microVM with its own kernel, so one tenant's code can never see or reach another's.

Cubes from $2.92/moNo credit card to sign up

01Why a Cube

Why run this on a Cube

Every line here is enforced by the platform rather than left to you: its own kernel per Cube, RAM and disk reserved 1:1, and full outbound access while nothing reaches in until you open a port — each one IP-allowlistable.

01

Real isolation per tenant

Every user's workload runs in its own microVM with its own kernel and a per-cube sandbox — never a shared kernel like a container. Isolated by design, multi-tenant-safe from the first line of code.

02

Nothing exposed

A Cube reaches the internet normally, but nothing reaches back in — there is no inbound route until you open a port, and each one is IP-allowlistable. A tenant's code can call the APIs it needs and still be unreachable from outside.

03

Provision and tear down by API

Spin up a fresh Cube for a new user in seconds and delete it just as fast — all through the v1 REST API or SDK. Take a snapshot first if you want a clean, reusable base image.

04

Pay only while it runs

Power a Cube off to stop compute billing the moment a session ends, and start it again in seconds when the user comes back. Billed by the minute, with RAM and disk reserved 1:1.

02Setup

How it works on a Cube

Wrap Cube provisioning behind your own app and hand each user a sealed environment.

  1. 01

    Create a Cube per user with a single API call, baking in your SSH key and a base image.

  2. 02

    Run the user's code inside the Cube with full root — no restrictions, its own kernel underneath.

  3. 03

    Keep every port closed except the ones your platform needs, each IP-allowlisted.

  4. 04

    Power the Cube off between sessions to pause billing, and delete it (with a pre-deletion backup) when the account goes away.

03Answers

Frequently asked questions

How is this different from running untrusted code in a container?

A container shares the host kernel with every other tenant on the box. A Cube is a Firecracker microVM with its own kernel and a per-cube sandbox, so the isolation boundary is VM-grade — the same technology behind AWS Lambda.

Can a tenant's Cube reach another tenant's Cube?

No. Cubes are isolated from one another by design and carry no inbound route from the internet until you open a port — you decide exactly which ports are reachable and from which IPs. Outbound access is unaffected: each Cube can still reach the internet normally.

How fast can I create a Cube per user?

A Cube boots in seconds. Create and destroy them programmatically through the SDK, CLI, or REST API as users come and go.

Launch your first Cube

Signing up is free — you'll be SSH'd into your own Cube in under a minute. Claim $5 in free credit — one-time, per account, and nothing is charged for it.