Third-Party Software Notices
Effective date: September 28, 2026
The short version
- Summer Engine is built on Godot Engine, which is free and open source under the MIT License. We are required to tell you that, and we are glad to: this document is the attribution.
- The Engine and Editor include many other open source libraries. Each is listed below with its license.
- The open source licenses grant you rights this document cannot take away. If anything here appears to conflict with an open source license, the open source license wins.
- Every Exported Game ships with an attribution file containing these notices. Creators must not remove it.
- If you think we got a license wrong, tell us at support@summerengine.com and we will fix it.
- Player terms, privacy and refund policies live at summer.games.
1. About this document
1.1 This document (the "Notices") identifies the third-party and open source software included in or distributed with the Summer Engine desktop application (the "Software", as defined in the Summer Engine Desktop EULA) and with the runtime embedded in Exported Games, reproduces the license notices those components require, and explains the attribution obligations that apply to Exported Games. Capitalized terms not defined here have the meanings given in the Summer Dictionary.
1.2 These Notices are published by Summer Labs, Inc., 2810 N Church St, STE 89812, Wilmington, DE 19802, United States, and are incorporated into the Summer Engine Desktop EULA, the Exported Game Runtime License and the Developer Tooling and API Terms.
1.3 Nothing in these Notices or in any Summer document limits, conditions or restricts any right granted to you by the license of a third-party component listed here. Each component is licensed to you by its copyright holders under its own license. If there is any conflict between a Summer document and a component's open source license, the open source license controls as to that component.
1.4 A machine-readable copy of these Notices, including the full text of every license referenced below, ships inside the Software (Help, About, Third-Party Licenses [SETTINGS PATH TO CONFIRM]) and inside every Exported Game as Section 8 describes.
2. Godot Engine
2.1 Summer Engine is a derived work of Godot Engine 4, the free and open source community-driven game engine. The Godot Engine source code is available at https://github.com/godotengine/godot. Godot and the Godot logo are trademarks of the Godot Foundation (Stichting Godot). Summer Engine is not affiliated with or endorsed by the Godot Foundation.
2.2 Godot Engine is licensed under the MIT License with the following copyright: Copyright (c) 2014-present Godot Engine contributors. Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.
2.3 The full text of the MIT License, which applies to Godot Engine and to every other component listed below as "MIT", is as follows: Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
2.4 FreeType credit. Portions of this software are copyright (c) The FreeType Project (www.freetype.org). All rights reserved. This credit is required by the FreeType License and must be preserved wherever these Notices are reproduced.
2.5 Godot logo and branding. The Godot Engine logo is copyright Andrea Calabro and licensed under CC BY 4.0. Summer Engine ships with Summer branding; if any build is found to include Godot logo assets, the CC BY 4.0 attribution applies to those assets. [ENGINEERING TO CONFIRM no Godot logo assets remain in shipped builds.]
3. Summer's modifications to Godot Engine
3.1 Summer maintains a fork of Godot Engine 4 with modifications for AI-native creation, Platform integration and Summer's Proprietary Modules. Summer's modifications to MIT-licensed Godot Engine source files are copyright (c) 2025-present [Summer Labs, Inc. and its affiliates].
3.2 The components of the Software licensed under the MIT License or another open source license ("Open Source Components") and the components proprietary to Summer ("Proprietary Modules") are identified in the Software's about screen. [SUMMER PROPRIETARY MODULE LIST, pending the open/proprietary split decision. Working position: the engine core and Editor remain MIT and are published in Summer's public fork repository; the CLI and MCP Server are open source under the license in their npm packages; the Proprietary Modules are the AI integration layer, cloud services client and Platform interoperability code.] The MIT License does not require Summer to publish the source code of its modifications; where Summer publishes source, the repository states its own license and contribution terms.
3.3 Nothing in this Section changes the license of upstream Godot Engine code, which remains under the MIT License with the copyright stated in Section 2.2. Summer's Proprietary Modules are not derivative works of any copyleft-licensed component and are not statically linked to any. [COPYLEFT AUDIT TO BE COMPLETED BEFORE LAUNCH.]
4. Engine third-party components
4.1 The Engine and Editor include the third-party libraries listed below. This table is derived from the Godot Engine thirdparty manifest as adapted in Summer's fork and is to be verified and completed by engineering against the fork's thirdparty/README.md and COPYRIGHT.txt before publication. [ENGINEERING TO COMPLETE: confirm the final shipped set, exact versions and per-component copyright lines.]
| Component | Function | License |
|---|---|---|
| AccessKit (accesskit) | Accessibility integration | MIT or Apache 2.0 |
| AMD FidelityFX Super Resolution (amd-fsr, amd-fsr2) | Upscaling | MIT |
| ANGLE | OpenGL ES translation layer | BSD 3-Clause |
| astcenc | ASTC texture compression | Apache 2.0 |
| Basis Universal (basis_universal) | Texture compression | Apache 2.0 |
| Brotli | Compression | MIT |
| Clipper2 | Polygon clipping | Boost Software License 1.0 |
| CVTT | Texture compression | MIT |
| D3D12 Memory Allocator (d3d12ma) | Direct3D 12 memory management | MIT |
| DirectX Headers (directx_headers) | Direct3D interfaces | MIT |
| doctest | Testing framework (non-shipping builds) | MIT |
| dr_libs | Audio decoding (WAV, FLAC, MP3) | MIT-0 or public domain |
| Embree | Ray tracing kernels (lightmapping, occlusion) | Apache 2.0 |
| ENet | UDP networking | MIT |
| etcpak | ETC texture compression | BSD 3-Clause |
| FreeType | Font rasterization | FreeType License (FTL), with the credit in Section 2.4 |
| glad | OpenGL loader | CC0 1.0 and Apache 2.0 |
| glslang | GLSL shader compilation | BSD 3-Clause, with portions under Apache 2.0 and other permissive licenses |
| Graphite | Smart font shaping | MIT |
| grisu2 | Floating point to string conversion | MIT |
| HarfBuzz | Text shaping | MIT (Old MIT) |
| ICU4C (icu4c) | Unicode and internationalization | Unicode License v3 |
| Jolt Physics (jolt_physics) | 3D physics | MIT |
| libbacktrace | Crash backtraces | BSD 3-Clause |
| libjpeg-turbo | JPEG images | BSD 3-Clause, IJG and Zlib |
| libktx | KTX texture container | Apache 2.0 |
| libogg | Ogg container | BSD 3-Clause |
| libpng | PNG images | PNG Reference Library License v2 |
| libtheora | Theora video | BSD 3-Clause |
| libvorbis | Vorbis audio | BSD 3-Clause |
| libwebp | WebP images | BSD 3-Clause |
| Manifold | Constructive solid geometry | Apache 2.0 |
| mbedTLS | TLS and cryptography | Apache 2.0 |
| meshoptimizer | Mesh optimization | MIT |
| minimp3 | MP3 decoding | CC0 1.0 |
| miniupnpc | UPnP port mapping | BSD 3-Clause |
| minizip | ZIP archives | Zlib |
| Monocypher | Cryptography | BSD 2-Clause or CC0 1.0 |
| msdfgen | Multi-channel signed distance fields (fonts) | MIT |
| OpenXR SDK (openxr) | XR runtime interface | Apache 2.0 |
| PCRE2 | Regular expressions | BSD 3-Clause |
| Recast Navigation (recastnavigation) | Navigation mesh generation | Zlib |
| RVO2 | Collision avoidance | Apache 2.0 |
| SDL | Input and platform services | Zlib |
| SMAA | Antialiasing | MIT |
| SPIRV-Cross (spirv-cross) | Shader cross-compilation | Apache 2.0 or MIT |
| SPIRV-Headers (spirv-headers) | SPIR-V headers | MIT |
| SPIRV-Reflect (spirv-reflect) | SPIR-V reflection | Apache 2.0 |
| ThorVG | Vector graphics (SVG, Lottie) | MIT |
| tinyexr | OpenEXR images | BSD 3-Clause |
| ufbx | FBX import | MIT |
| V-HACD (vhacd) | Convex decomposition | BSD 3-Clause |
| volk | Vulkan meta-loader | MIT |
| Vulkan Headers and utilities (vulkan) | Vulkan interface | Apache 2.0 |
| Vulkan Memory Allocator | Vulkan memory management | MIT |
| wslay | WebSocket protocol | MIT |
| xatlas | UV atlas generation | MIT |
| zlib | Compression | Zlib |
| Zstandard (zstd) | Compression | BSD 3-Clause |
4.2 Bullet note. Godot Engine 4 no longer bundles the Bullet physics library; 3D physics is provided by Jolt Physics (MIT) and Godot Physics. Portions of Godot's convex hull computation code (core/math/convex_hull.cpp and convex_hull.h) derive from the Bullet Continuous Collision Detection and Physics Library, copyright (c) 2011 Ole Kniemeyer, MAXON, licensed under the Zlib license. [ENGINEERING TO CONFIRM whether any listing of Bullet as a bundled library is needed; current analysis says no.]
4.3 Platform-specific components. Some components ship only on certain operating systems (for example ANGLE and D3D12 components on Windows; Wayland client libraries, X11-related headers and linuxbsd_headers on Linux). The per-platform manifest is included in the machine-readable notices. [ENGINEERING TO COMPLETE.]
5. Fonts, certificates and data files
5.1 Fonts. The Editor bundles fonts including the Noto font family (SIL Open Font License 1.1) and the Hack font (MIT, with portions under the Bitstream Vera license). The complete font list and copyright lines are in the machine-readable notices. [ENGINEERING TO COMPLETE from thirdparty/fonts.] 5.2 TLS root certificates. The Software includes a root certificate bundle derived from Mozilla's CA certificate store, licensed under the Mozilla Public License 2.0. The corresponding source form is available at https://curl.se/docs/caextract.html and in Summer's published notice materials. 5.3 Public domain and CC0 materials are identified in the machine-readable notices.
6. Updater, runtime and tooling components
6.1 The Summer Engine desktop application additionally includes or installs the following components that are not part of upstream Godot Engine. [ENGINEERING TO COMPLETE: confirm final shipped set and versions.]
| Component | Function | License |
|---|---|---|
| Sparkle 2.7.0 (build 2044) | macOS software update framework | MIT. Copyright (c) 2006-2013 Andy Matuschak. Copyright (c) 2009-2013 Elgato Systems GmbH. Copyright (c) 2011-2014 Kornel Lesiński. Copyright (c) 2015-2017 Mayur Pawashe. Copyright (c) 2014 C.W. Betts. Copyright (c) 2014 Petroules Corporation. Copyright (c) 2014 Big Nerd Ranch. Bundled components under their own licenses: bsdiff and bspatch (BSD 2-Clause, Copyright 2003-2005 Colin Percival); sais-lite (MIT, Copyright (c) 2008-2010 Yuta Mori); portable C implementation of Ed25519 (Zlib, Copyright (c) 2015 Orson Peters); SUSignatureVerifier.m (BSD 2-Clause, Copyright (c) 2011 Mark Hamlin). The full Sparkle LICENSE file is reproduced in the machine-readable notices. |
| Velopack [VELOPACK VERSION TO CONFIRM: the fork pins no version; the native library (velopack_libc_win_x64_msvc.dll, velopack.lib) is supplied outside the repository and the vpk tool is unpinned, last recorded 0.0.1298] | Windows installation and update framework | MIT. Copyright (c) 2021 Caelan Sayler. Copyright (c) 2024 Velopack Ltd. No bundled third-party notices. |
| Microsoft Edge WebView2 Loader (webview2) | Embedded web content on Windows | Microsoft WebView2 SDK license (BSD 3-Clause form), reproduced in full; the WebView2 Runtime is not redistributed |
| .NET Runtime (dotnet) | C# scripting support | MIT |
| ripgrep | Project-wide search | MIT or Unlicense |
| git | Local version control integration | GPL 2.0 (separate program, aggregated; source at [GIT SOURCE URL]; see 6.2 and 9.2); bundled on macOS; Windows uses a system git until bundled |
| summer-engine CLI and MCP Server | Command line and agent tooling (npm package summer-engine) | [LICENSE; working position: open source, license stated in the npm package] |
6.2 Components that are separate programs invoked by the Software (rather than linked into it) are aggregated with, not combined with, the Software; each remains under its own license, and nothing in the Summer Engine Desktop EULA restricts your rights in them.
7. Web platform open source
7.1 The Summer Games web platform is built with open source software, including the Next.js framework and other JavaScript, TypeScript and infrastructure components. The web platform's notices are published at [URL: web platform open source notices page]. [TO COMPLETE: generate from the web repository's dependency manifest before public launch.]
8. Attribution in Exported Games (note for Creators)
8.1 Every Exported Game produced with the Editor automatically includes an attribution file (the Notices File defined in the Exported Game Runtime License) containing: (a) the Godot Engine MIT notice in Section 2; (b) the FreeType credit in Section 2.4; (c) the license notices for every third-party component included in the export template used; (d) Summer's own runtime notices under the Exported Game Runtime License; and (e) the Attribution Manifest for Asset Library assets under the Asset Library License Terms.
8.2 You must not remove, hide or alter the attribution file or its contents. This is both a condition of the Exported Game Runtime License and, independently, a legal obligation you owe to the third-party copyright holders: licenses such as MIT, FTL, Apache 2.0 and the BSD licenses require that their copyright and permission notices accompany copies and substantial portions of the licensed software, and an Exported Game contains such copies. Removing the notices can expose you, not just Summer, to infringement claims. No third-party licensor is a beneficiary of the Exported Game Runtime License or of these Notices; each licensor's rights arise only under its own license.
8.3 You may present the attributions in your own credits screen in addition to (but not instead of) the bundled attribution file. The Godot Engine project publishes credit logos and guidance at https://godotengine.org/license/; using them is welcome but not required.
8.4 If you incorporate additional third-party assets or libraries into your Game, you are responsible for complying with their licenses and extending your Game's attributions accordingly.
9. Copies of licenses and source code
9.1 The full text of every license referenced in these Notices is included in the machine-readable notices shipped with the Software and with every Exported Game. 9.2 Where a component's license requires access to source code (for example MPL 2.0 for the certificate bundle, or GPL 2.0 if the git component ships as described in Section 6), Summer will provide the corresponding source or a written offer as required. The corresponding source for the git component is published at [GIT SOURCE URL]. Requests: support@summerengine.com, subject line "Source request". 9.3 Upstream Godot Engine source code is at https://github.com/godotengine/godot. Summer's public fork repository, as designated under Section 3.2, is at [REPOSITORY URL].
10. Reporting a license concern
10.1 If you believe the Software includes a component that is not properly attributed, is used inconsistently with its license, or should be listed here and is not, contact support@summerengine.com with the subject line "Open source notice", identifying the component, the license you believe applies, and where you observed the issue. We review every report and correct confirmed errors in the next release of the Software and of these Notices. 10.2 Copyright infringement claims regarding content on the Platform are handled under the DMCA and Intellectual Property Policy, not under this Section. 10.3 Security vulnerabilities in any component should be reported under the Vulnerability Disclosure Policy.