Fourfold
Third-party notices & content credits
AvailablePrepared for Fourfold 1.9.0 on 7 October 2026. Versions below are the installed/resolved versions, not just the version ranges in package.json.
Fourfold includes third-party software and fonts. Their owners retain their copyrights. The publisher's original-content reuse permission does not replace these licenses. Keep the applicable license texts and notices with copies of the components. Links to full local texts are provided below; distribute those files with this notice.
Web runtime, native bridge, fonts, and icons
| Component and installed version | Copyright/credit | License and included text | Project |
|---|---|---|---|
| React 19.3.0 | Meta Platforms, Inc. and affiliates | MIT | React |
| React DOM 19.3.0 | Meta Platforms, Inc. and affiliates | MIT | React DOM |
| Scheduler 0.28.0 | Meta Platforms, Inc. and affiliates | MIT | React Scheduler |
| Capacitor Core 8.5.2 | 2017–present Drifty Co. | MIT | Capacitor |
| Capacitor Android 8.5.2 | 2017–present Drifty Co. | MIT | Capacitor Android |
| Capacitor App 8.1.1 | 2020–present Ionic | MIT | App plugin |
| Capacitor Filesystem 8.1.4 | 2025 Ionic | MIT | Filesystem plugin |
| Capacitor Share 8.0.3 | 2020–present Ionic | MIT | Share plugin |
| DM Sans / Fontsource package 5.3.0 | 2014 The DM Sans Project Authors; exact installed font notice retained | SIL Open Font License 1.1 | DM Sans sources, Fontsource |
| Lucide React 0.468.0 | 2022 Lucide Contributors; inherited portions credited to Cole Bemis, 2013–2022 | ISC; inherited Feather MIT | Lucide, Feather |
| Workbox Window 7.4.1 | 2018 Google LLC | MIT | Workbox |
| Workbox Core 7.4.1 | 2018 Google LLC | MIT | Workbox |
| Workbox Precaching 7.4.1 | 2018 Google LLC | MIT | Workbox |
| Workbox Routing 7.4.1 | 2018 Google LLC | MIT | Workbox |
| Workbox Strategies 7.4.1 | 2018 Google LLC | MIT | Workbox |
MIT and ISC permit broad reuse subject to their notice conditions. DM Sans can be used and distributed under the OFL; its requirements for font redistribution, modifications, and any reserved font names still apply. The OFL does not require documents or images made using the font to adopt the OFL. Read the included licenses for the actual conditions.
Android runtime libraries
The resolved release runtime graph contains 55 external module coordinates, including 51 with cached binary artifacts and four metadata/variant coordinates. The full versioned list and embedded notices are in Android Runtime Components. Gradle's original report and a machine-readable inventory accompany the publication package.
| Library family | License, credits, and reference |
|---|---|
| AndroidX: Activity, AppCompat, annotations, architecture components, collection, concurrency, CoordinatorLayout, Core, splash screen, cursor adapter, custom view, drawer layout, Emoji2, Fragment, interpolator, Lifecycle, Loader, resource inspection, SavedState, Startup, tracing, vector drawables, versioned parcelables, ViewPager, WebKit | The Android Open Source Project and respective contributors. Apache 2.0; retain the version-specific embedded notices linked in the component list. AndroidX source. |
| Apache Cordova Android framework 14.0.1 | Apache Software Foundation. Release LICENSE and release NOTICE. Version 14.0.1 source. |
| Ionic ionfilesystem-android 1.1.1 | 2025 Ionic. MIT. Project and upstream license. |
| Kotlin standard library 2.2.20 | JetBrains and respective contributors. Apache 2.0. Versioned Kotlin source and license information. The accompanying upstream Kotlin NOTICE identifies the broader compiler project; the app includes its runtime standard library, not the compiler. |
| kotlinx.coroutines Core/JVM and Android 1.10.2 | JetBrains and Kotlin Programming Language contributors; exact notice retained in the Apache 2.0 license. Versioned project. |
| JetBrains Java annotations 23.0.0 | JetBrains and respective contributors. Apache 2.0. Versioned project. |
| Google Guava ListenableFuture 1.0 | Google and respective contributors. Apache 2.0. Guava source. |
| JSpecify 1.0.0 | JSpecify contributors. Apache 2.0. Versioned project. |
Apache 2.0 includes notice, modification-marking, patent, and trademark provisions. A link alone is not a substitute for distributing the required license and applicable notices. Fourfold's broad content license cannot waive these requirements.
Original content and artwork
Original app code and authored content are credited to Leutrim and any respective contributors. The permission in the Terms and Conditions applies only to rights the publisher can grant.
The app's maple and walnut textures, carved counters, Go stones, wooden X/O pieces, and decorative smoke/ash artwork were generated during this project's development using OpenAI image-generation tools. Production assets include maple-v6.webp, walnut-v2.webp, wood.webp, pieces-v6.webp, symbols-v6.webp, and smoke-v7.webp. The app icon and interactive board geometry are implemented as project SVG/vector graphics. Piece sounds are synthesized by project code rather than taken from a recorded music or sound-effects library.
The project retains asset provenance in its design records and source artwork folder. Some older concepts are development references rather than shipped interface images. There is no claim that generated art has exclusive copyright protection. This credit does not imply endorsement by OpenAI or any library author, and no OpenAI runtime service is used for gameplay.
Game rules and educational references
Fourfold implements classic game mechanics for Mills, Tic-tac-toe, English Draughts, and 9×9 Go. It does not claim ownership of those game mechanics. In-app explanations, authored positions, lessons, puzzles, and diagrams are project content, subject to the rights described above.
Go reference materials consulted include the British Go Association's How to Play and Comparison of Some Go Rules. Those external pages and their text and images are not licensed by Fourfold. The app's Go variant uses positional superko, prohibits suicide, and uses area scoring with 6.5 komi. A reference credit does not mean the BGA approves the app.
Development tools and platform-specific scope
Vite, its React plugin, vite-plugin-pwa, the Capacitor CLI, Playwright, Node.js, Python, Gradle, and Android build tools are used during development. They are not all distributed as app runtime components. The Workbox runtime emitted by the PWA build is separately credited above. Test-only JUnit, Espresso, Mockito, and org.json dependencies are not part of the release runtime inventory.
No iOS app project or resolved iOS release exists in this workspace at this audit date. Capacitor Filesystem's package declares an additional Ionic iOS filesystem dependency for iOS. Its exact resolved version, license and notice files, and any other iOS dependencies must be added from the actual iOS build before distribution. This Android inventory is not an iOS inventory.