Codewriter90x · Codewriter90x · Aug 19, 2026 · Aug 19, 2026 · Aug 19, 2026
@@ -34,6 +34,8 @@ jobs:
           persist-credentials: false
       - name: Validate public-readiness contracts
         run: bash tests/scripts/public-readiness-contract-tests.sh
+      - name: Validate MPL licensing contracts
+        run: bash tests/scripts/licensing-contract-tests.sh
       - name: Validate website localization contracts
         run: bash tests/scripts/website-localization-contract-tests.sh
       - name: Validate public Wiki contracts

@@ -4,9 +4,9 @@ Thank you for helping make HitTheKit more reliable, accessible, and useful.
 
 Before participating, read the [Code of Conduct](CODE_OF_CONDUCT.md),
 [support guide](SUPPORT.md), and [project governance](GOVERNANCE.md).
-HitTheKit is intended to remain available under both an open-source GPL license
-and a possible separate commercial-license path. That model requires clear
-copyright permissions for every substantial contribution.
+HitTheKit is intended to remain available under both the open-source MPL-2.0
+Community license and a possible separate commercial-license path. That model
+requires clear copyright permissions for every substantial contribution.
 
 ## Current contribution policy
 

@@ -54,7 +54,7 @@ help without creating a recurring commitment:
   accessibility, and focused development time a meaningful one-time boost.
 
 Custom monthly and one-time support remains available through GitHub Sponsors.
-Rewards are digital, low-maintenance, privacy-conscious and independent of GPL
+Rewards are digital, low-maintenance, privacy-conscious and independent of MPL
 rights. Sponsorship does not purchase guaranteed features, roadmap control,
 private GoMyRO access, commercial-song rights or a commercial HitTheKit license.
 

@@ -1,66 +1,68 @@
 # HitTheKit Licensing
 
-HitTheKit is intended to be available under a dual-licensing model.
-
-This repository currently grants the Community license under version 3 of the
-GNU General Public License. No project-specific "or any later version" grant
-was found during the licensing audit, so the current grant is treated as
-GPL-3.0-only. The complete, unmodified license text is in [`LICENSE`](LICENSE).
+HitTheKit uses a dual-licensing model.
 
 ## Community license
 
-The Community edition may be used, studied, modified, shared, and used
-commercially under the GNU General Public License version 3, provided that the
-applicable GPL obligations are respected.
+Unless a file or directory says otherwise, original HitTheKit source code is
+available under the [Mozilla Public License 2.0](LICENSE) (MPL-2.0).
+Third-party components, Unity packages, generated engine material, trademarks,
+and content retain their own terms; see
+[THIRD_PARTY_NOTICES.md](THIRD_PARTY_NOTICES.md), [NOTICE](NOTICE), and
+[TRADEMARKS.md](TRADEMARKS.md).
+
+The MPL permits personal, educational, community, and commercial use. When
+MPL-covered source files are modified and distributed, those covered files
+must remain available under the MPL. A larger work may contain separate files
+under other terms, provided the MPL requirements for covered files are met.
+The full license text controls; this overview does not replace it.
+
+## Unity players and other executable distributions
 
-In particular, conveying modified or combined covered works may require
-providing corresponding source code and licensing the covered work under the
-GPL. Consult the full GPL text for the actual terms; this overview does not
-replace it.
+MPL-2.0 permits covered HitTheKit code to be distributed in a larger executable
+under different terms while preserving recipients' rights to the MPL-covered
+source. This removes the former GPL whole-work copyleft concern for a player
+that incorporates the proprietary Unity Runtime.
+
+It does not itself approve a particular binary release. Every macOS or Windows
+candidate must still satisfy the applicable Unity terms, dependency notices,
+asset and content rights, signing requirements, platform testing, and the
+project release checklist. Unity and third-party technology are not relicensed
+by HitTheKit.
 
 ## Commercial license
 
-A separate commercial license may be available for organizations or
-individuals that want to use HitTheKit under terms incompatible with the GPL,
-including use within proprietary or closed-source products. Possible use cases
-include:
+A separate commercial license may be available to organizations or individuals
+that need terms different from MPL-2.0, including:
 
-- proprietary desktop or mobile applications;
-- closed-source training platforms;
-- commercial hardware integrations;
-- bundled products;
-- private-label or white-label distributions; and
-- redistribution without GPL copyleft obligations for HitTheKit code.
+- keeping modifications to MPL-covered HitTheKit files proprietary;
+- proprietary hardware or software integrations;
+- bundled, private-label, or white-label distribution; or
+- separately negotiated support, warranty, or maintenance terms.
 
-The commercial license is not automatically granted by this repository.
-Commercial terms require a separate written agreement with a copyright holder
-who has authority to license the relevant code. Such an agreement covers only
-the rights that licensor controls; it does not replace licenses or commercial
-terms for Unity or any other third-party component.
+The commercial license is not automatically granted and is not required merely
+because an activity generates revenue. It requires a separate written agreement
+with a copyright holder authorized to license the relevant code. It cannot
+replace Unity's terms or the licenses of third-party components.
 
-## Personal, educational, and commercial use
+## Existing GPL copies
 
-Personal, educational, and community use is welcome under the GPL Community
-license. No commercial license is required merely because an activity
-generates revenue, provided that the use and any distribution comply with the
-GPL.
+Copies validly received under GPL-3.0-only before the MPL relicensing remain
+available to their recipients under GPL-3.0-only. The MPL change does not revoke
+rights already granted. A recipient must use the license offered for the exact
+copy or version they received.
 
 ## Contributions
 
-Contributions require separate governance rules so that the project can remain
-eligible for dual licensing. See [`CONTRIBUTING.md`](CONTRIBUTING.md).
+Future contribution terms must preserve a clear rights chain for both the MPL
+Community edition and any separate commercial licensing. Until that mechanism
+has been reviewed and adopted, follow [CONTRIBUTING.md](CONTRIBUTING.md).
 
 ## No trademark permission
 
-The software license does not automatically grant permission to use the
-HitTheKit name, logo, or branding to market a modified or competing product.
-Trademark rights, if any, are separate from copyright licensing. See
-[`TRADEMARKS.md`](TRADEMARKS.md).
-
-## Contact
-
-Commercial licensing inquiries: open a private inquiry with the copyright
-holder. A dedicated contact address will be published later.
+MPL-2.0 does not grant permission to use the HitTheKit name, logo, or branding
+to market a modified or competing product. Truthful attribution remains
+permitted. See [TRADEMARKS.md](TRADEMARKS.md).
 
 This document is a project licensing overview, not legal advice and not a
-substitute for the full GPL text or a signed commercial agreement.
+substitute for the MPL text or a signed commercial agreement.
@@ -3,18 +3,18 @@ HitTheKit public source notice
 Copyright (c) 2026 HitTheKit contributors and the respective rightsholders
 identified in COPYRIGHT.md.
 
-Original HitTheKit source code is made available under GPL-3.0-only. See
-LICENSE. Third-party software and tools retain their own licenses and notices;
-see THIRD_PARTY_NOTICES.md.
+Unless stated otherwise, original HitTheKit source code is made available under
+MPL-2.0. See LICENSE and LICENSING.md. Third-party software and tools retain
+their own licenses and notices; see THIRD_PARTY_NOTICES.md.
 
 This source repository contains no commercial recordings, stems, MIDI files,
 lyrics, transcriptions, album artwork, or download links. Player-owned local
 content is outside the repository and remains the player's responsibility.
 
-The initial public publication is source-and-website only. No Unity player
-binary is approved for public distribution. Unity-runtime redistribution and
-the proposed separate commercial-license path remain subject to qualified
-legal review and are not granted by this notice.
+No Unity player binary is approved merely by this notice. Each binary candidate
+must independently pass the Unity terms, dependency, provenance, signing,
+platform-testing, and release gates. The proposed separate commercial-license
+path requires a written agreement and is not granted by this notice.
 
 HitTheKit is independent and is not sponsored, endorsed, certified by, or
 affiliated with Unity Technologies, Apple Inc., or referenced hardware

@@ -5,7 +5,7 @@
 
 <p align="center">
   <img alt="Version 0.5.0 pre-release" src="https://img.shields.io/badge/version-0.5.0--pre--release-ff4fa3">
-  <img alt="License GPL-3.0-only" src="https://img.shields.io/badge/license-GPL--3.0--only-2fe0ff">
+  <img alt="License MPL-2.0" src="https://img.shields.io/badge/license-MPL--2.0-2fe0ff">
   <img alt="Unity 6" src="https://img.shields.io/badge/Unity-6000.5.6f1-ffffff">
   <img alt="MIDI support macOS only" src="https://img.shields.io/badge/MIDI-macOS%20CoreMIDI-f6a623">
   <a href="https://github.com/sponsors/Codewriter90x"><img alt="Sponsor HitTheKit" src="https://img.shields.io/badge/Sponsor-GitHub%20Sponsors-EA4AAA?logo=githubsponsors&logoColor=white"></a>
@@ -176,8 +176,9 @@ hardware result, improve documentation or pick a
 ## Licensing and content boundary
 
 Original project code is licensed under
-[GPL-3.0-only](LICENSE). A possible separate commercial-license path is under
-preparation and remains subject to legal review; see [LICENSING.md](LICENSING.md).
+[MPL-2.0](LICENSE). A separate commercial-license path remains available only
+through a written agreement; see [LICENSING.md](LICENSING.md). Existing copies
+previously received under GPL-3.0-only retain those rights.
 
 The public repository does not include commercial songs, recordings, charts,
 lyrics or artwork. Third-party names describe compatibility only. HitTheKit is

@@ -15,8 +15,8 @@ documented, and represented honestly in the release notes.
   reduced motion;
 - publish screenshots, checksums, known limitations, and reproducible release
   notes from the exact candidate commit; and
-- complete professional review of GPL, Unity distribution, contribution, and
-  commercial-licensing terms.
+- validate the MPL-based Unity distribution, contribution, and
+  commercial-licensing terms for the exact release candidate.
 
 ## Next: broader compatibility and confidence
 

@@ -8,7 +8,7 @@ provenance is recorded separately in
 
 | Component | Version | Declared license or terms | Role | Redistributed by this repository? | Review status / action |
 | --- | --- | --- | --- | --- | --- |
-| Unity Editor and built-in Unity modules | Editor 6000.5.6f1; modules 1.0.0 | Unity Terms of Service and Unity Editor Software Terms | Authoring, compilation, runtime APIs | Editor and module source/binaries are not tracked; a future player build may contain Unity runtime components | **Legal review required:** confirm current plan eligibility, player redistribution, GPL interaction, and separate Unity permission for embedded systems. |
+| Unity Editor and built-in Unity modules | Editor 6000.5.6f1; modules 1.0.0 | Unity Terms of Service and Unity Editor Software Terms | Authoring, compilation, runtime APIs | Editor and module source/binaries are not tracked; a future player build may contain Unity runtime components | Confirm current plan eligibility, player redistribution terms, required notices, and separate Unity permission for embedded systems for every candidate. MPL-2.0 does not relicense Unity. |
 | Unity Test Framework | 1.7.0 | Unity Companion License v1.4 | EditMode and PlayMode testing | Package source is resolved by Unity Package Manager, not tracked or intended for player distribution | Preserve the package license and copyright notice if substantial package portions are redistributed. |
 | Unity Custom NUnit (`com.unity.ext.nunit`) | 2.1.0, based on NUnit 3.5 | Unity Package Distribution License v2.1; bundled NUnit portions under MIT | Transitive Unity test dependency | Resolved by Unity Package Manager, not tracked or intended for player distribution | Preserve Unity package terms and the bundled NUnit MIT notice when applicable. |
 | .NET SDK | 8.0.411 requested by `global.json` | MIT plus the distribution's third-party notices | Build tooling | No | Build tool only; follow the license and notices of the installed distribution. |
@@ -21,7 +21,7 @@ provenance is recorded separately in
 
 ## Verified sources
 
-- GNU GPL version 3: <https://www.gnu.org/licenses/gpl-3.0.html>
+- Mozilla Public License 2.0: <https://www.mozilla.org/MPL/2.0/>
 - Unity terms: <https://unity.com/legal/terms-of-service>
 - Unity Companion License: <https://unity.com/legal/licenses/unity-companion-license>
 - Unity Package Distribution License:

@@ -1,10 +1,10 @@
 # HitTheKit Name and Branding
 
-The GPL license for HitTheKit source code does not itself grant trademark
+The MPL-2.0 license for HitTheKit source code does not itself grant trademark
 rights in the HitTheKit name, logo, or other project branding. No claim that a
 mark is registered is made here.
 
-The GPL permits recipients to copy, modify, and distribute covered code under
+MPL-2.0 permits recipients to copy, modify, and distribute covered code under
 its terms. A fork may identify the code it came from in a truthful, descriptive
 way, but should not imply sponsorship, endorsement, certification, or official
 status that has not been granted.
@@ -14,7 +14,7 @@ brand for a modified, competing, private-label, or commercial product. Any
 separate branding permission should be documented in writing.
 
 This guidance is provisional and requires legal review. It does not restrict
-the copyright permissions granted by the GPL.
+the copyright permissions granted by MPL-2.0.
 
 ## Third-party names
 

@@ -70,7 +70,8 @@ without creating an unreviewed second source of truth.
 
 - [Asset provenance](legal/ASSET_PROVENANCE.md)
 - [Dual-licensing readiness report](legal/dual-licensing-readiness-report.md)
-- [Dual-licensing decision record](governance/dual-licensing-decision.md)
+- [MPL Community license decision](governance/mpl-community-license-decision.md)
+- [Historical GPL dual-licensing proposal](governance/dual-licensing-decision.md)
 - [Commercial-license draft](legal/COMMERCIAL-LICENSE-DRAFT.md)
 - [Project governance](../GOVERNANCE.md)
 - [License](../LICENSE)

@@ -14,7 +14,9 @@ Build and package it with Unity `6000.5.6f1`:
 The script builds the native plug-in, synchronizes Core, invokes the checked-in
 Unity build method, embeds the arm64 plug-in, applies an ad-hoc signature,
 verifies the bundle, and creates a resource-fork-safe ZIP under
-`artifacts/game/`.
+`artifacts/game/`. The application and ZIP include `Legal/` with the MPL text,
+project and third-party notices, and `SOURCE-CODE.txt`, which identifies the
+exact public Git revision corresponding to the build.
 
 This playtest packaging is intentionally not a production distribution flow.
 Unity gives the local build an ad-hoc signature, but downloading it on another

@@ -72,7 +72,10 @@ is the simpler and safer release procedure.
 `build-macos-distribution-app.sh` builds the native arm64 CoreMIDI plug-in,
 synchronizes the managed Core assembly, and asks Unity to create a non-
 Development macOS player. The bundle identifier remains
-`com.codewriter90x.hitthekit`.
+`com.codewriter90x.hitthekit`. Before signing, it installs the MPL license,
+project notice, third-party notices, licensing overview, and an exact-revision
+`SOURCE-CODE.txt` under `Contents/Resources/Legal`. The final DMG exposes the
+same `Legal/` directory at its top level.
 
 `sign-macos-app.sh` signs a staged copy and replaces the input only after the
 staged bundle passes strict verification. It signs every nested Mach-O first,

@@ -20,7 +20,9 @@ Build and package with:
 
 The script synchronizes the tested Core assembly, asks Unity for a clean
 `StandaloneWindows64` player, rejects a package containing the CoreMIDI native
-plug-in, adds player instructions, creates a ZIP, and prints its SHA-256.
+plug-in, adds player instructions and a `Legal/` directory, creates a ZIP, and
+prints its SHA-256. `Legal/SOURCE-CODE.txt` identifies the exact public Git
+revision for the MPL-covered HitTheKit files in that executable distribution.
 Generated output remains under the ignored `artifacts/game` directory.
 
 The Windows player contains `HitTheKit.exe`, `HitTheKit_Data`, Unity runtime
@@ -41,6 +43,13 @@ test the exact ZIP on clean Windows 10 and Windows 11 machines:
 6. confirm Device Setup states clearly that production MIDI is macOS-only; and
 7. collect logs and screenshots without personal paths or third-party content.
 
+## MIDI support
+
+Installing Unity Windows Build Support enables player compilation only. It
+does not provide production MIDI input. Windows electronic-drum support needs
+a separately implemented and tested Windows MIDI backend; until then the
+Windows player is keyboard-only.
+
 ## Signing and public distribution
 
 The current script intentionally creates an **unsigned playtest**. It is not a

@@ -1,9 +1,14 @@
 # Dual-Licensing Decision Record
 
-Status: `PROPOSED_PENDING_LEGAL_REVIEW`
+Status: `SUPERSEDED_BY_MPL_COMMUNITY_LICENSE_DECISION`
 
 Date: 2026-08-05
 
+> Historical record. The project subsequently adopted MPL-2.0 as its Community
+> license. See
+> [MPL Community License Decision](mpl-community-license-decision.md). Existing
+> GPL copies retain the rights already granted to their recipients.
+
 ## Decision
 
 HitTheKit will preserve its Community edition under GNU General Public License