The control plane ships
Today we are releasing ActantOS v1.2.0 Quiet Open-Core — the self-host Enforcement Kernel that decides whether an AI agent may perform a tool action before that action runs.
This is not another agent framework. ActantOS is an in-path, fail-closed runtime control plane: policy, approvals, sandbox, and audit outside the agent's process.
Public release: github.com/kotobuki09/actantos-releases/releases/tag/v1.2.0
Product page: /v1
Why this matters
Coding agents and MCP tools can read files, run shell, and call external systems with little independent oversight. Prompt filters and post-hoc dashboards do not stop a dangerous tool call. Teams need a deterministic gate:
- Intercept the tool call
- Evaluate Cedar policy + risk rules + budgets + kill switch
- Return allow, deny, or approval_required
- Only then may execution proceed — with a bound decision token and hash-chained evidence
If ActantOS is down, adapters fail closed. Nothing silently executes.
What's in Quiet Open-Core
| Capability | Status |
|---|---|
Frozen /v1 API | Yes |
| Cedar policy bundles + risk rules | Yes |
| Web approval (one-use, TTL) + optional Slack | Yes |
Pi Primary Path (guarded_* coding tools) | Yes |
| MCP gateway (optional) | Yes |
| Docker sandbox, kill switch, budgets, rate limits | Yes |
| Audit hash-chain + evidence export | Yes |
| Balanced coding policy (default) / Strict (opt-in) | Yes |
Free to self-host. Multi-tenant Firecracker-class isolation and full commercial managed SaaS remain Stage 3 — not required to run the kernel or Stage 2 ops today. Optional OIDC for operator routes and Compose-hosted single-tenant path ship in Stage 2.
The path to v1
v1.2.0 is the public cut after the full engineering ladder: demo hardening → MCP → self-host → policy/budget → security → pilot readiness. The version path is complete. The open-core tag is live.
Ship criterion
v1.2.0 means:
- Installable open-core kernel
- Automated verification path (typecheck, tests, policy regression, compose smoke demo)
- Frozen API for integrators
Built and tests pass = done. No design-partner program or external proof gate is required. Stage 2 Control Plane later completed under the same rule — see Stage 2 announcement.
Demo story
Against a local actantosd, the smoke demo exercises:
- Safe workspace read → allow
- Credential /
.envread → deny git push→ approval_required- One-use approval → allow
- Kill switch → next action deny
- Evidence export
That is the Pilot Workflow coding teams care about.
Get started
git clone https://github.com/kotobuki09/actantos-releases.git
cd actantos-releases
cp actantosd/.env.example actantosd/.env
docker compose -f actantosd/docker-compose.yml up -d --build
cd actantosd && npm install
npm run demo -- --url http://localhost:3100
What's next (updated)
- Stage 2 Control Plane — done: see ActantOS Stage 2 Control Plane Is Complete
- Stage 3 isolation (Firecracker-class), WORM, and productized SIEM when built and tests pass
Links
- How to use at work: /blog/how-to-use-actantos-at-work
- Release celebration: /v1
- Stage 2 story: /blog/actantos-stage-2-control-plane
- GitHub release: v1.2.0
- Docs quickstart: /docs
- Kernel deep-dive / playground: /mvp
- Changelog: /changelog
The kernel is shippable. Stage 2 ops are live. Install it. Stress the decision loop. Use the dashboards.