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License Overview

Kitsu is free and open source software licensed under the GNU Affero General Public License version 3.0 (AGPL-3.0).
What does this mean for you?You are free to use, modify, and distribute Kitsu, even for commercial purposes, as long as you comply with the license terms.

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Quick Summary

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You Are Free To:

Use

Use Kitsu for any purpose, including commercial projects

Study

Study how the software works and adapt it to your needs

Share

Distribute copies to help others

Modify

Modify the software and distribute your modifications

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Your Responsibilities:

1

Share Source Code

If you distribute Kitsu or modified versions, you must make the source code available under the same AGPL-3.0 license.
2

Preserve License

Include the original license and copyright notices in your distributions.
3

Document Changes

Clearly mark any modifications you make to the software.
4

Network Use Clause

If you run a modified version on a network server, you must make the source code available to users who interact with it.

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The AGPL-3.0 License

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Key Provisions

You may run the program for any purpose, without restrictions on who can use it or what they can use it for.
You have access to the source code and can modify it to suit your needs. The source code is a prerequisite for this freedom.
You can distribute copies of the original software to help others, with or without charge.
You can distribute your modified versions, so the whole community can benefit from your improvements.
If you run a modified version of Kitsu on a server and let others interact with it there, you must make the modified source code available to those users.This is the key difference between AGPL and GPL - it closes the “SaaS loophole” by requiring source code disclosure even when the software is only accessed over a network.
Kitsu - Production Management Software (user interface)
Copyright (C) CGWire
Author: Frank Rousseau <[email protected]>

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published
by the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.

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Common Questions

Yes, if you only use it internally and don’t distribute it to others or provide access over a network to users outside your organization.However, if you run a modified version as a service accessible to external users (e.g., clients, contractors), you must make your modifications available under AGPL-3.0.
Yes, you can charge for distributing Kitsu or modified versions. However, recipients must receive the source code and the same freedoms you received under AGPL-3.0.
This depends on how they’re implemented:
  • If they’re separate programs that communicate with Kitsu through its API, they may not need to be AGPL.
  • If they’re integrated into Kitsu’s codebase or form a combined work, they must be AGPL.
When in doubt, consult with a legal professional.
The size of modifications doesn’t matter. If you distribute modified versions or run them on a network server, you must make the source code available under AGPL-3.0.
Yes, you can integrate Kitsu with proprietary software through its API. API integration typically doesn’t create a derived work, so your proprietary software doesn’t need to be AGPL.

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Compliance Guidelines

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If You Distribute Kitsu

1

Include License

Include the full AGPL-3.0 license text with your distribution.
2

Provide Source Code

Make the complete source code available, including any modifications you’ve made.
3

Document Changes

Clearly indicate what changes you’ve made and when.
4

Preserve Notices

Keep all copyright and license notices intact.

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If You Run Kitsu as a Network Service

1

Original Version

If you run the unmodified version, no additional action needed beyond what the license requires.
2

Modified Version

If you run a modified version accessible to users over a network:
  • Provide a way for users to access the modified source code
  • Include installation instructions
  • Make it prominently available (e.g., link in the UI)

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Full License Text

The complete GNU Affero General Public License v3.0 is available in:

View Full License

Read the complete AGPL-3.0 license text on GitHub

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Why AGPL?

CGWire chose the AGPL-3.0 license to ensure that:
  1. Community Benefits: Improvements made by anyone benefit the entire community
  2. Transparency: Users can see exactly what the software does
  3. Network Protection: The “Affero” clause prevents the SaaS loophole
  4. Freedom: Studios maintain freedom to use and modify the software
  5. Collaboration: Encourages open collaboration and shared improvements

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Contribution License

By contributing to Kitsu, you agree to license your contributions under the AGPL-3.0 license. All contributions must follow the C4 contract. See the Contributing Guide for more information.

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Third-Party Licenses

Kitsu uses various third-party open source libraries, each with their own licenses:
  • Vue.js: MIT License
  • Vuex: MIT License
  • Vue Router: MIT License
  • Vite: MIT License
  • ESLint: MIT License
  • Prettier: MIT License
  • Chart.js: MIT License
  • FullCalendar: MIT License
  • Fabric.js: MIT License (custom fork)
See package.json for a complete list of dependencies and their respective licenses.
All third-party licenses are compatible with AGPL-3.0.

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Commercial Support

While Kitsu is free software, CGWire offers commercial support and services:
  • Professional support contracts
  • Custom development
  • Training and consulting
  • Hosted solutions

CGWire Services

Learn about professional support options

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Disclaimer

No WarrantyKitsu is provided “as is” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and fitness for a particular purpose.See the full license text for complete warranty disclaimers and limitations of liability.
Not Legal AdviceThis page provides a general overview of the AGPL-3.0 license as it applies to Kitsu. It is not legal advice. For legal questions about license compliance, consult with a qualified legal professional.

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Questions About Licensing?

If you have questions about licensing or compliance:

Contributing

How to contribute to Kitsu

C4 Contract

Contribution guidelines

GitHub Repository

View the source code

GNU AGPL-3.0

Official license text

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