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paiOS Docs

ADR-001: Licensing Strategy

Status

Section titled “Status”

Accepted (2026-01-15)

Context

Section titled “Context”

paiOS is a commercial open-source project that needs to:

  1. Protect the core runtime from being forked without contributing back
  2. Allow proprietary extensions for any developer or commercial partner
  3. Ensure long-term sustainability – flexibility for future business models
  4. Maintain simplicity – avoid “Qt licensing pain”

The runtime communicates with extensions via gRPC over Unix Domain Sockets (IPC), similar to how Linux kernel syscalls create a boundary between the GPL kernel and user-space applications.

Decision

Section titled “Decision”

We adopt a “Default AGPL, with Permissive Exceptions” model:

  • Default: All files are licensed under AGPL-3.0 (per root LICENSE file).
  • Exception: Subdirectories with their own LICENSE file override the default.
pai-os/
├── LICENSE              (AGPL-3.0 = default for everything)
├── NOTICE               (Copyright & Trademarks)
│
│   ✅ FREE TO USE (Apache-2.0)
├── api/                 ← All API definitions
│   └── grpc/
├── apps/                ← Your extensions go here
│
│   🔒 MUST SHARE CHANGES (AGPL-3.0)
├── engine/              ← Runtime code
├── os/
├── scripts/
└── docs/

Contributor License Agreement (CLA)

Section titled “Contributor License Agreement (CLA)”

We require a CLA (replacing DCO) to grant aurintex the right to:

  • Ensure long-term sustainability – flexibility for future business models
  • Maintain the project indefinitely with proper resources
  • Protect the project’s right to defend its trademarks

IPC Boundary as License Boundary

Section titled “IPC Boundary as License Boundary”

The gRPC/UDS communication between runtime and extensions creates a clear process separation:

flowchart TB
    subgraph ext["✅ Your Extension"]
        ext_label["Any license you want!<br/>Proprietary, MIT, Apache, closed..."]
    end
    
    ext -->|"gRPC over UDS<br/>(License Boundary)"| runtime
    
    subgraph runtime["🔒 paiOS Runtime"]
        runtime_label["AGPL-3.0"]
    end
    
    style ext fill:#1a4d1a,stroke:#4ade80,color:#fff
    style ext_label fill:#1a4d1a,stroke:#4ade80,color:#fff

This follows the same pattern as:

  • Linux Kernel (GPL) + User-space apps (any license)
  • Docker Engine (Apache-2.0) + Plugins (any license)

Shared Memory Constraint

Section titled “Shared Memory Constraint”

Rule: Shared memory may only be used for raw byte buffers (images, audio PCM). Control signals and handles must go through gRPC.

Consequences

Section titled “Consequences”

Positive

Section titled “Positive”
  • ✅ Clear separation: Runtime protected, extensions open
  • ✅ B2B customers can write proprietary extensions
  • ✅ Apache-2.0 provides patent protection for extension developers
  • ✅ CLA enables future business model flexibility
  • ✅ Simple: Only 2 licenses to understand

Negative

Section titled “Negative”
  • ⚠️ AGPL may deter some enterprise adopters (but this is intentional)
  • ⚠️ CLA adds friction for contributors (mitigated by CLAassistant)
Section titled “Related”