Last reviewed: 30 September 2026.
PSoXide is an independent PlayStation development project. This page explains the licences covering its code, the separate rights affecting game content, and what each project distributes. Technical compatibility and public availability do not establish permission to copy, adapt or redistribute third-party material.
Code and licences
The SDK, emulator, editor and engine are released under GPL-2.0-or-later. The Quake port is GPL-2.0-only. File-level notices and third-party licences remain applicable; a repository’s top-level licence does not grant rights that its contributors do not hold. Project-specific restrictions on third-party content are separate from the GPL permissions for code.
Using a PSoXide tool does not automatically place everything it produces under the GPL. However, distributing a program that incorporates or links PSoXide’s GPL-covered runtime or SDK generally requires licensing the combined program consistently with the GPL and providing its complete corresponding source, including required build material. This is not limited to changes to PSoXide itself.
Separately licensed art, music and other independent content retain their own terms. Permission to use assets bundled with a demonstration does not automatically extend to your own release. The GPL permits commercial distribution of covered code, subject to its conditions; that does not override restrictions on bundled music, game data or other third-party material.
See the GNU GPL FAQ for the distinction between tool output, combined programs and independent content.
Source for distributed builds
Source must correspond to the binary being distributed, including modifications
and the build scripts required by the applicable licence. A link to a moving
main branch alone does not identify that source. This applies to browser
WebAssembly downloads as well as native executables and code on disc images.
The release source references identify verified v0.40 revisions and outstanding source-availability checks.
The demo-disc source repository and emulator source repository contain the build tooling. Check the release’s source revision and component pins, rather than assuming that today’s source matches an older download. If a release does not identify its corresponding source, report the release URL and version so the missing information can be addressed.
Ports and reimplementations
Porting or rewriting a game does not remove the rights in its original code or content. These projects require a suitable licence, permission or another applicable legal basis. PSoXide’s own licence grants no rights to third-party games.
Requiring your own lawfully obtained copy avoids supplying the original game data. It does not, by itself, grant permission to adapt or redistribute that data, including converted files and completed disc images. Source availability, noncommercial status, attribution and a rights holder’s silence do not by themselves establish permission either.
Each project must distinguish its own code, source-informed adaptations and game assets. Rewriting code in another language is not, by itself, evidence of an independent implementation. See the UK Intellectual Property Office’s guidance on copyright permissions.
Provenance
Development uses AI coding agents under human direction, review and testing. The agents wrote nearly all of the code; how PSoXide is built lists the rules they work to and the checks each change passes. Known upstream derivations are credited in the source and provenance records. PSoXide does not claim a clean-room development process or guarantee that provenance reviews identify every third-party influence.
Parts of the emulator core still derive from PCSX-Redux (GPL-2.0-or-later), including the event scheduler, DMA, SPU envelopes, the MDEC pipeline and SIO. Those files carry a provenance header that names PCSX-Redux, and the project's licence notice lists the same lineage. The high-level kernel emulation does not: it is written from public hardware documentation and console measurements (see No BIOS). The CD-ROM module dropped its Redux references on 4 October 2026, but three of its delay values (for GetID, Pause and Stop) are still PCSX-Redux's, because replacing them changes the compatibility results. Other components were implemented using public hardware documentation and console observations. Behavioural comparisons and similarity scans are evidence with a defined scope, not proof of the absence of all derivation.
See the licence audit and HLE provenance record. Historical audit results describe the revisions and files they examined.
No BIOS
The current PSoXide emulator implements kernel services through its own Rust high-level emulation (HLE). It does not require or load a Sony BIOS image; the external BIOS-loading paths were removed in September 2026. The SDK targets the hardware without requiring Sony’s proprietary SDK.
The HLE provenance record says the kernel is written from public hardware documentation (the nocash psx-spx notes) and from measurements: which kernel functions games call, and timings taken on a console. It states that other kernel implementations and SDKs (OpenBIOS, PCSX-Redux, nugget, psyqo and PSn00bSDK) are not read while the kernel is written and that nothing is translated from them, and that code once derived from one of them was deleted and written again in October 2026; the git history shows those rewrites as commits that start with "Rewrite". The record's policy excludes Sony BIOS bytes, disassembly, fonts, logos, boot sounds and kernel memory images from committed implementation and fixtures. This describes the current implementation and recorded checks, not an unlimited guarantee about every historical copy, fork or artifact.
The firmware-cleanup record documents the removal work. BIOS-free operation does not settle separate rights in games, assets or console modifications.
Commercial games
The emulator can open user-supplied software. The project does not distribute retail commercial disc images; its browser player offers the public PSoXide Demo Disc. That compilation includes third-party content with separate terms, so it should not be treated as wholly project-owned or wholly GPL-licensed content.
Compatibility listings describe testing, not endorsement or permission to obtain or share a game. Screenshots and video likewise do not grant rights in the works shown. Use only material you are entitled to use for the intended purpose.
Ports built from other people's games
Half-Life
HL-PSX is an unofficial, noncommercial, source-only compatibility project. Its Rust implementation was informed by Valve’s public Half-Life SDK, and its provenance record identifies adaptations from GPL-licensed Quake code. Users provide their own lawfully obtained Half-Life installation; project releases do not include Valve game assets, converted asset packs or completed disc images.
Valve’s Half-Life SDK licence has its own scope and conditions. HL-PSX runs on a separate runtime; the project’s distribution policy does not establish that Valve’s terms authorize every aspect of this work. See HL-PSX licensing and source provenance.
Hollow Knight
An experiment that cooks rooms, sprites, text and audio from a local install. Those files belong to their owners, the project's licence gives no rights to them or to their converted form, and footage is public on Bonnie Studios' YouTube channel, but there is no public build.
Quake
The port's engine code is GPL-2.0-only. Its current disc image includes converted Quake shareware data and SLICNSE.TXT. That data has separate terms covering modification, derivative works and distribution. See the bundled shareware licence and port provenance.
Celeste Classic Collection
An unofficial, non-commercial fan port of the two PICO-8 games, Celeste (2016) and Celeste 2: Lani's Trek (2021) by Maddy Thorson and Noel Berry, with Celeste 2's music by Lena Raine. The levels, art and music are theirs. PICO-8 is by Lexaloffle Games. The port isn't affiliated with or endorsed by any of them. Its code licence does not grant rights in the original games’ assets.
Music and other assets
- Just Music: four tracks, used in NitroXide and on the demo disc menu with the artist's permission. Non-commercial; don't redistribute the audio on its own.
- Goncharov by magikAAAAArp: used in Magikaaaaarp Pong with the band's permission, and so is their album art.
- Carmelo Miceli: the Cortex Ignition menu and combat music, written for the game and used with the composer's permission.
- Models, textures, sounds and fonts: sources and licences are tracked in project records, including unresolved provenance items. Examples include the Torment Textures pack (with attribution) and the VT323 font (SIL Open Font License) in the SDK's asset-provenance.md, and Kenney's CC0 interface sounds in the Celeste credits.
Running burned discs on original hardware
A standard, unmodified retail PlayStation cannot directly boot a burned PSoXide disc. As with other burned PS1 discs, you need a modchipped console or another compatible homebrew boot method.
PSoXide does not endorse console modchipping or provide instructions or assistance for installing modchips. Modifying a console can permanently damage it or render it unusable (“brick” it). Any modification is undertaken at your own risk.
This is a hardware requirement and risk notice, not permission to modify hardware or bypass protections. Applicable law and third-party rights remain relevant. The browser player requires no console modification.
Trademarks
PlayStation is a trademark of Sony Interactive Entertainment Inc. Half-Life is a trademark of Valve Corporation. Other game and product names belong to their respective owners and identify the works or compatibility being discussed. PSoXide is not affiliated with, sponsored by or endorsed by Sony, Valve or the other rights holders named here.
Warranty and liability
Software is provided under its applicable licence, including that licence’s warranty disclaimers and limitations of liability. This website does not add a warranty or grant rights in third-party material. Nothing here excludes rights or liabilities that applicable law does not allow to be excluded.
This page explains project policies and documented terms. It is not legal advice or legal clearance for a particular use. For a decision about your own project, especially commercial distribution or third-party adaptations, consult a qualified IP lawyer.
Contact
For a rights, attribution, licensing or source-availability concern, open an issue at EBonura/PSoXide. Identify the affected page, file or release, the work concerned, and the basis of your concern. Where relevant, include the applicable licence or a public source for the attribution.
GitHub issues are public. Do not post confidential correspondence, private personal information, BIOS files or game assets. If supporting evidence is confidential, state that a private follow-up is needed without posting the evidence itself.