Open source

Nautilus is AGPL-3.0. Every domain service, every frontend, every Helm chart, every doc. Cruise operators get full source. Integrators can audit and contribute. Tenants who need closed-source rights can buy a commercial license — same code, different rights.

This page lays out the license model, the three-tier integration model, the crypto-audit commitment, and how to contribute.

License model

AGPL-3.0 by default

The full Nautilus source is released under the GNU Affero General Public License version 3.

• Use it. Fork it. Modify it. Deploy it.
• Network-use clause: if you offer a modified Nautilus as a service to third parties, you publish your modifications under AGPL.
• AGPL is the same license used by MongoDB (formerly), Grafana Labs, Element / Matrix, Plausible, and many other production-grade open-source platforms.

Optional commercial license

For tenants who need:

• Closed-source derivatives or OEM bundles.
• Contractual SLAs and indemnification.
• The ability to deploy a modified Nautilus as a service without AGPL's network-use disclosure obligations.

Same code, different rights. Includes commercial support, security-patch guarantees, and indemnification.

Comparing the two tracks

Both tracks ship the same software. The choice is about your distribution model, not your features.

Talk to NT Connect about a commercial license →

The three-tier integration model

Nautilus is organized into three tiers with different licensing and openness postures. The model is designed so any third party can build a Nautilus-compatible integration without using a single line of NT Connect's commercial code.

Tier A — Open primitives

Permissively licensed. Foundational. Everyone uses these.

Tier B — Closed services

Commercial NT Connect products. Run them yourself via the published interfaces, or use NT Connect's managed services.

• Quanta — auth, messaging-service, keys-service, websocket-gateway, push, media, group, admin, video.
• ConnectOne — Cloud PBX, signaling, media platform.
• CallCraft — AI-voice agent runtime inside ConnectOne.
• Heimdall — DeBERTa-v3 multi-task analysis service + 12 content-safety plugins.

Tier C — Documented interfaces

Anyone can implement against these specs and integrate without using NT Connect's closed services. Specifications are CC BY 4.0; reference stubs and conformance harnesses are Apache 2.0.

Browse Tier-C specs →

Crypto-audit commitment

Tier A contains cryptographic primitives — the Signal-Protocol library and the PSI module. We are committed to specialist crypto audits before public release, not after.

• $250–400k budget committed across three audit phases.
• Three phases: PSI module → Signal-Protocol library → multi-tenant hardening + JWT lifecycle.
• Shortlist: Least Authority and Trail of Bits as paired primary auditors. NCC Group as fallback.
• Audit reports published alongside library releases as a credibility asset, not buried.

The bus + agent contract release does not gate on the crypto audit. The crypto-bearing libraries do.

Contributing

Nautilus accepts contributions under a CLA following the Apache ICLA + CCLA pattern. Contributors retain copyright; NT Connect Holdings, Inc. holds a license sufficient to dual-license under AGPL and the commercial license.

What's in the repo

• CONTRIBUTING.md — how to contribute, review process, commit conventions.
• SECURITY.md — security disclosure policy and contact.
• CODE_OF_CONDUCT.md — community standards.
• LICENSE — AGPL-3.0.
• LICENSES/COMMERCIAL.md — pointer to the commercial license terms (negotiated separately).
• CLA.md — the contributor license agreement.
• ADRs in docs/adr/ — architectural decision records, public.
• Public roadmap and public issue tracker.

How to start

• Read CONTRIBUTING.md.
• Sign the CLA.
• Pick a "good first issue."
• Open a PR.

Where we particularly want help

• CRS adapter authors for systems beyond Versonix Seaware.
• GRMS hardware integrators for cabin lighting, HVAC, drapes, locks across KNX / BACnet / DALI / vendor adapters.
• Regulatory-reporting specialists for jurisdictions beyond the initial set.
• Per-tenant launch partners willing to be Phase-1 / Phase-2 reference vessels.

Read CONTRIBUTING → Sign the CLA → Browse good-first-issues →

What "open source" means here, specifically

We say "open source the way Signal did it" deliberately. That means:

• Audited cryptographic primitives. Not "trust us — we encrypt."
• Published interface specs, with conformance harnesses, so third parties can build compliant integrations without our code.
• Public roadmap, public issue tracker, public ADRs. Decisions and trade-offs are visible.
• CLA + dual-license so the project is sustainable as both an open community and a commercial product. We chose this pattern after watching projects that stayed pure-AGPL struggle with commercial-customer needs and projects that went pure-commercial lose their community.
• No "open core." Tier A is genuinely open. Tier B is genuinely commercial. Tier C makes the boundary auditable. There's no hidden "premium" tier of features locked behind a paywall inside the AGPL distribution.

What we don't do

• No "source available" license dressed up as open source. AGPL-3.0 is OSI-approved.
• No telemetry phoning home from the AGPL distribution by default. Self-hosted means self-hosted.
• No closed CSAM-detection black box. Heimdall's CSAM path uses PhotoDNA + Thorn with NCMEC reporting per 18 USC 2258A; the wiring is auditable.
• No "open core" feature gating. AGPL Nautilus is the same software as commercial Nautilus.

For developers → For integrators → Tier-C spec index →