Phaethon

Terms

The licenses Phaethon's software comes under, and what you need to play.

The launcher

The Phaethon launcher is proprietary software. The license it shows during setup governs its use, including its terms for game data, updates, Discord presence and warranty.

The runtime

The runtime, the compiler and the decompiler come under two licenses, by who wrote what:

  • Phaethon's own work, everything added since the fork left OpenGOAL's jak-project, is under the PolyForm Strict License 1.0.0: you may use it, build it and play it; you may not distribute it, and you may not make changes or new works based on it.
  • The code inherited from OpenGOAL stays under the ISC License with the OpenGOAL Team's copyright notice.

Both licenses give the software as it is, without a warranty.

The games

You need your own copy of each game you play. Phaethon ships no game data and downloads none: the launcher reads every file from your own disc or an image you made from it. Phaethon is an unofficial fan project, not affiliated with, endorsed by or associated with Sony Interactive Entertainment or Naughty Dog. Jak and Daxter is a trademark of Sony Interactive Entertainment.

Questions

Write to hello@playphaethon.com.

Phaethon

Built with AI in the loop. Phaethon uses AI assistance for speed and accuracy, and holds it to the same bar as every other contribution: every change is read, tested and checked against the console before it lands.

develop f183c49b CI green v0.2.0-rc6 26 Sep 2026