# Third-Party Notices for ASysT

ASysT is distributed as a Visual Studio Code extension (`.vsix`) that **bundles** the
third‑party open‑source components listed below. Each is used under its own license. License
texts are reproduced here or, for the EPL-2.0 model corpus, shipped beside the complete source.

ASysT's own code is © 2026 Juce and is covered by the root [`LICENSE`](LICENSE) /
[`asyst-vscode/LICENSE.txt`](asyst-vscode/LICENSE.txt). The components below are **not**
ASysT's work; they retain their own copyright and license. ASysT's proprietary code remains
separate from those components and does not override their licenses.

> Scope: this file enumerates the components that are **redistributed inside the shipped
> artifact** — the frontend (embedded in the engine binary), the engine's Go dependencies
> and the Go runtime, the bundled SysML language server, the bundled Node.js runtime, and the
> redistributed SysML v2 Release model source.
> Build‑only tools (Vite, ESLint, Vitest, TypeScript, esbuild, vsce, …) are **not** shipped
> and are therefore not listed. Before any *public* distribution, regenerate an exhaustive
> manifest with license tooling (`license-checker`, `go-licenses`, and Node's own notices)
> — see `_Docs/_01REVIEW/04_Tooling_and_Launch.md` (artifact-content and release audit).

---

## What ships, and what it bundles

| Component | Role in the shipped artifact | License |
|---|---|---|
| **React**, **React‑DOM** | frontend UI framework (Vite‑built, embedded in the engine binary via `go:embed`) | MIT |
| **React Flow** (`@xyflow/react`) | the diagram canvas | MIT |
| **Zustand** | frontend state stores | MIT |
| **html‑to‑image** | client‑side SVG/PNG export | MIT |
| **go‑chi/chi** v5 | engine HTTP router | MIT |
| **gorilla/websocket** | engine WebSocket transport | BSD‑2‑Clause |
| **gopkg.in/yaml.v3** | engine YAML (rendering/session sidecars) | MIT **and** Apache‑2.0 |
| **Go runtime & standard library** | compiles & runs the engine binary | BSD‑3‑Clause |
| **sysml‑v2‑lsp** (daltskin) | the SysML v2 language server (`asyst-vscode/lsp/`) | MIT |
| └ bundled into the LSP: **vscode‑languageserver** / **‑textdocument** | LSP framework | MIT |
| └ bundled into the LSP: **antlr4ng** | ANTLR4 TypeScript runtime (the SysML parser) | BSD‑3‑Clause |
| └ bundled into the LSP: **zod** | LSP schema validation | MIT |
| **Node.js runtime** (`bin/node`) | runs the bundled LSP | MIT (+ its own third‑party notices) |
| **SysML v2 Release model corpus** (`2026-04`) | 309 upstream examples, training, validation, and library models | Eclipse Public License 2.0 |

ASysT's own bridge (`asyst-vscode` `extension.js`), engine, frontend, docs, and ASysT-authored
demo models are covered by ASysT's license. The separately identified SysML v2 Release corpus is
third-party source covered by EPL-2.0.

ASysT uses only the MIT-licensed open-source `@xyflow/react` package. It does not incorporate React Flow
Pro examples, templates, support services, or subscription-only material. The package's optional visible
canvas promotion is hidden through its public `proOptions.hideAttribution` API; the MIT licence itself has
no on-screen attribution, subscription, royalty, or payment condition. The required React Flow copyright
and MIT permission notice remain reproduced below and travel with the distributed product.

---

## License texts

### 1. MIT License

Applies to: **React**, **React‑DOM**, **React Flow** (`@xyflow/react`), **Zustand**,
**html‑to‑image**, **go‑chi/chi**, **sysml‑v2‑lsp**, **vscode‑languageserver** /
**‑textdocument**, **zod**, the **Node.js** core, and the MIT‑licensed portions of
**gopkg.in/yaml.v3**. Each retains its own copyright notice:

- React, React‑DOM — Copyright (c) Meta Platforms, Inc. and affiliates.
- React Flow (`@xyflow/react`) — Copyright (c) 2019‑2025 webkid GmbH
- Zustand — Copyright (c) 2019 Paul Henschel
- html‑to‑image — Copyright (c) 2017‑2025 W.Y.
- go‑chi/chi — Copyright (c) 2015‑present Peter Kieltyka (https://github.com/pkieltyka), Google Inc.
- sysml‑v2‑lsp — Copyright (c) 2026 Jamie Dalton
- vscode‑languageserver, vscode‑languageserver‑textdocument — Copyright (c) Microsoft Corporation
- zod — Copyright (c) 2020 Colin McDonnell
- Node.js — Copyright Node.js contributors. All rights reserved.

The MIT license text (identical for all of the above) is:

```
MIT License

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
```

---

### 2. BSD‑2‑Clause — gorilla/websocket

```
Copyright (c) 2013 The Gorilla WebSocket Authors. All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

  Redistributions of source code must retain the above copyright notice, this
  list of conditions and the following disclaimer.

  Redistributions in binary form must reproduce the above copyright notice,
  this list of conditions and the following disclaimer in the documentation
  and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
```

---

### 3. BSD‑3‑Clause — Go runtime & standard library, and antlr4ng

The Go standard library and runtime (statically linked into the engine binary):

```
Copyright 2009 The Go Authors.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

   * Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
   * Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.
   * Neither the name of Google LLC nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
```

**antlr4ng** (the ANTLR4 TypeScript runtime, inlined into the LSP bundle) is licensed
under the same BSD‑3‑Clause terms — Copyright (c) The ANTLR Project. See
https://github.com/mike-lischke/ANTLR4ng for the authoritative notice.

---

### 4. gopkg.in/yaml.v3 — MIT and Apache‑2.0 (verbatim upstream LICENSE)

```
This project is covered by two different licenses: MIT and Apache.

#### MIT License ####

The following files were ported to Go from C files of libyaml, and thus
are still covered by their original MIT license, with the additional
copyright staring in 2011 when the project was ported over:

    apic.go emitterc.go parserc.go readerc.go scannerc.go
    writerc.go yamlh.go yamlprivateh.go

Copyright (c) 2006-2010 Kirill Simonov
Copyright (c) 2006-2011 Kirill Simonov

Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
of the Software, and to permit persons to whom the Software is furnished to do
so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

### Apache License ###

All the remaining project files are covered by the Apache license:

Copyright (c) 2011-2019 Canonical Ltd

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
```

---

### 5. Node.js runtime

The bundled `node` executable (`asyst-vscode/bin/node`) is distributed under the Node.js
license (MIT, above) and **itself includes** additional third‑party components — V8
(BSD‑3‑Clause), libuv (MIT), OpenSSL (Apache‑2.0), zlib, c‑ares, and others — each under
its own permissive license. The complete and authoritative set of those notices is the
`LICENSE` file shipped within the Node.js distribution and published at
https://github.com/nodejs/node/blob/main/LICENSE . That notice travels with the bundled
binary and is incorporated here by reference.

---

### 6. SysML v2 Release model corpus — Eclipse Public License 2.0

ASysT redistributes 309 `.sysml` source models from
[`Systems-Modeling/SysML-v2-Release`](https://github.com/Systems-Modeling/SysML-v2-Release),
release `2026-04`, commit `9baca5908ca28b53da085de69336fde48420ea8f`.

The complete corresponding model source, upstream `README.md`, and authoritative EPL-2.0
`LICENSE` travel inside both ASysT distributions at:

`Demo/Official_OMG_SysML_v2/SysML-v2-Release-2026-04/`

The imported `.sysml` files are unchanged. See `UPSTREAM.md` in that directory for provenance,
corpus counts, and the non-endorsement notice.

These models are redistributed under the Eclipse Public License 2.0. ASysT is an independent
product and is not affiliated with, sponsored by, certified by, or endorsed by OMG.

SysML® and OMG® are registered trademarks of Object Management Group, Inc.

---

*Updated 2026‑07‑15 from the on-disk license files and pinned upstream corpus. If you update a
bundled dependency or corpus release, refresh the corresponding entry here.*
