Kosa8

What is Kosa8

Kosa8 provides secure, isolated virtual machines (microVMs) for running and managing AI agents. Each agent operates in its own sealed machine with a dedicated kernel, ensuring that it only accesses explicitly granted resources. These sandboxes can be checkpointed, copied, and rewound in about a second, allowing for safe experimentation and rapid recovery from errors. Kosa8 runs on Mac, Linux, and Windows (via WSL2), and can also be deployed in the cloud or air-gapped environments. It is Docker-compatible and MCP-native, with a Claude Code plugin available.

How to use Kosa8

1. Install Kosa8 by running the one-line installer: curl -fsSL https://kosa8.com/install.sh | sh. The installer detects your system, verifies the download, and adds Kosa8 to your PATH.
2. Verify your environment with kosa8 doctor, which checks for prerequisites and provides fixes for any issues.
3. Run an agent in a sealed sandbox using a command like kosa8 agent run claude. This launches a coding agent in its own VM with only the specified workspace visible and network access restricted.
4. Manage sandboxes with commands to fork, checkpoint, rewind, or export evidence. For example, kosa8 fork api -n 8 creates eight live copies of a running sandbox.

Features of Kosa8

• Sealed microVMs: Each agent gets its own VM with a separate kernel, not a shared container.
• Fast checkpoint and rewind: Save, copy, and rewind a sandbox in about one second.
• Closed network with egress broker: Network access is closed by default; allowed connections go through a broker that injects API keys without exposing them to the sandbox.
• Docker-compatible: The Docker CLI and Compose work unchanged through a Docker-compatible API.
• MCP-native: Supports Model Context Protocol servers, each in its own sandbox behind a unified policy.
• Human approvals: Risky actions require approval from one or two named approvers.
• Tamper-evident audit trail: Every action is hash-chained and marked as human or agent, enabling third-party verification.
• Local models: Run local models with OpenAI- and Anthropic-compatible APIs.
• Cross-platform: Runs on Apple-silicon Macs, x86-64 Linux, and Windows 11 (WSL2 preview); also available for cloud and air-gapped deployments.
• Signed releases: Every release is signed, and the installer refuses unverified downloads.
• FIPS 140-3 builds: Available for regulated industries.

Use Cases of Kosa8

• Software teams: Run coding agents like Claude Code and Codex unattended without exposing host credentials or keys. Each agent sees only the project folder, and network access is restricted.
• AI product teams: Give each user task its own VM, fork running machines to test multiple solutions, and isolate third-party MCP servers.
• Security and SOC: Detonate malware samples in sealed VMs with simulated internet, generate signed reports, and create disposable training ranges for analysts.
• Regulated industries: Meet audit requirements with hash-chained evidence, two-person approvals, signed org policies, and air-gapped operation.
• Founders and small teams: Let agents run overnight on a local Mac with checkpoint and rewind, using local models to avoid API costs.

Pricing

Kosa8 offers four plans:

• Solo: $29/month. One person, one assistant running. 4 concurrent sandboxes, 64 GB sandboxes.
• Pro: $89/month. One person driving a fleet of assistants. 16 concurrent sandboxes, 128 GB sandboxes.
• Team: $169/person/month. For teams with someone accountable for security. From 3 people. 48 shared sandboxes, 256 GB sandboxes.
• Scale: $199/person/month. For large fleets needing dedicated capacity. From 5 people. 160 shared sandboxes, 500 GB sandboxes.

A 14-day free trial is available with no credit card required. Yearly billing gets two months free.

FAQ

Do I need a card or an account to try it?
No. One line installs it, and every feature works for 14 days. Nothing to sign up for until you choose a plan.

What happens after the 14 days?
Kosa8 is paid software; there is no permanently free tier. Plans start at $29 a month, and paying yearly gets two months free.

Does my code or data leave my machine?
No. Your code, files, and prompts stay where the sandbox runs—your computer, your cloud, or an air-gapped network. Kosa8 checks your licence, and plans with usage limits report counts (how many forks, snapshots, restores—never what ran) from an audit log you can verify. An offline licence sends nothing at all.

Will it slow my agents down?
A container starts in 178 ms and a running sandbox restores in 897 ms, measured on real hardware. A folder shared from your computer reads at about a third of native speed, so keep heavy builds inside the sandbox.

Which computers does it run on?
Apple-silicon Macs and x86-64 Linux run sandboxes themselves; Windows 11 on x86-64 does too, through WSL2 (preview). An Intel Mac, Windows 10 or ARM, and JioOS pair with one of those in one command.

Do I have to change how my team works?
No. The Docker CLI and Compose keep working, and ready-made kits run Claude Code, Codex, Gemini, and other agents with one command: kosa8 agent run claude.

We are a regulated company. Can we use it?
Yes. Kosa8 offers FIPS 140-3 builds, signed org policies, two-person approvals, CUI labels, air-gapped operation, and signed evidence packages. Contact for Enterprise & Government options.