# Third-party components

Nothing here is proprietary. Everything is taken unmodified from upstream unless noted.

| Component | Used for | License | Source |
|---|---|---|---|
| v86 (`libv86.js`, `v86.wasm`) 0.5.472 | x86 PC emulator running both DOS machines, NE2000 NIC, DHCP/DNS responder | BSD-2-Clause | https://github.com/copy/v86 |
| SeaBIOS and VGABIOS (inside `assets.b64.js`) | BIOS of the emulated PCs, as shipped with v86 | LGPL-3.0 / LGPL-2.1+ | https://github.com/copy/v86/tree/master/bios |
| FreeDOS 1.4 Floppy Edition (kernel, FreeCOM) | DOS on the boot floppy (`dosmqtt.img` inside `assets.b64.js`) | GPL-2.0 | https://www.freedos.org/ |
| Crynwr NE2000 packet driver 11.4.3 (`NE2000.COM`) | DOS driver for the emulated NE2000 card | Crynwr "freely copyable; source must be available" (GPL-style); source: Crynwr packet drivers 11.x | http://www.georgpotthast.de/sioux/packet.htm , https://archive.org/details/PKTD11A_ZIP |
| mTCP 2026-10-10 by Michael B. Brutman (`DHCP.EXE`, TCP/IP library) | DHCP client (unmodified binary) and the TCP/IP stack linked into A.EXE and B.EXE | GPL-3.0-or-later | http://www.brutman.com/mTCP/ |
| Open Watcom 1.9 | Compiler used to build A.EXE and B.EXE (not distributed) | Sybase Open Watcom Public License | https://openwatcom.org/ |

`A.EXE` and `B.EXE` are built from `src/a.cpp`, `src/b.cpp` and `src/mqtt.h` plus the mTCP library sources
(`TCPLIB/`, `TCPINC/` of the mTCP source archive). `src/build.sh` shows the exact compiler options.
`src/make_image.sh` assembles the boot floppy and `src/build_assets.py` packs it into `assets.b64.js`.

The Gradio demo sends the typed question to a third-party public Gradio Space (default `tencent/Hy3`) over HTTPS and prints its reply; that service has its own terms and the reply is not our content.
The MQTT brokers (broker.emqx.io, test.mosquitto.org, broker.hivemq.com) are third-party public services.
No credentials are used.