Licence

01In brief

02What “free for personal use” means

You can use Akatsuki for yourself, and share a self-hosted copy with your household and friends, for free, as long as nobody pays. Anything commercial is reserved: using it in or for a business, use by any organisation (including non-profits, schools and public bodies), selling it or offering it as a hosted service needs written permission from the copyright holder first. That reservation lets the hosted service pay for Akatsuki’s development, while the code stays open for anyone who wants to check what an email client does with their mail. Because it reserves commercial use, ASAL-1.0 is not an OSI-approved licence.

03Self-hosting

Self-hosting is free for personal, non-commercial use. You bring your own Google and Microsoft OAuth clients and your own AI provider, or run a model locally. Setup instructions will be published with the source. Using Akatsuki for a business, self-hosted or not, needs a commercial licence: write to sami@samihindi.com.

04Contributions

You keep the copyright in what you contribute. By contributing you grant the copyright holder a perpetual, irrevocable licence to use and relicense your contribution, including commercially. The details are in section 6 of the licence.

05Third-party components

Libraries Akatsuki uses keep their own licences. The Convex backend is licensed under FSL-1.1-Apache-2.0; if you run it yourself you follow that licence too. The hosted service, Akatsuki Pro, is covered by its own terms of service, not by this licence.

06The full licence

This summary is for convenience. The licence text below is what applies.

Akatsuki Source-Available License
Version 1.0 (ASAL-1.0)

Copyright (c) 2026 Sami Hindi. All rights reserved, except as granted below.

Akatsuki is open source, free for personal use. You may read, run and change
it for personal, non-commercial purposes. Commercial use of any kind,
including use by any organisation, needs written permission from the
copyright holder first (sami@samihindi.com). Because it reserves commercial
use, this licence is not approved by the Open Source Initiative (OSI).

The summary below is for convenience only. The numbered terms that follow it
are the licence; if the two ever disagree, the numbered terms win.


SUMMARY
-------

  You may
    - Read and study the source code.
    - Run Akatsuki for yourself, including self-hosting it on your own
      machine or server.
    - Let members of your household and your friends use your self-hosted
      copy, as long as nobody pays anything for it.
    - Change the code for your own use.
    - Publish the source code of your changes (for example a public fork or
      a pull request), free of charge, under this same licence.
    - Compile Akatsuki and share the builds with anyone, free of charge,
      under this same licence (see section 3.4).
    - Contribute changes back to the project (see section 6).

  You may not
    - Use Akatsuki in or for a business, or for any commercial purpose.
    - Sell Akatsuki, or sell access to it.
    - Offer Akatsuki to others as a hosted or managed service.
    - Bundle Akatsuki, or any part of it, into a paid product.
    - Use Akatsuki to provide any service for a fee.
    - Sublicense Akatsuki, or relicense it under different terms.
    - Remove or change copyright, licence or attribution notices.
    - Use the Akatsuki name or logo for your own copy or product.

  Ask first (write to sami@samihindi.com)
    - Any of the "may not" uses above.
    - Use by an organisation of any kind, including non-profits, schools and
      public bodies.
    - Using a self-hosted copy for business email, including your own
      freelance or company mail.
    - Anything you are unsure about.


TERMS
-----

1. Definitions

   1.1 "Licensor" means Sami Hindi, the copyright holder.

   1.2 "Software" means the Akatsuki source code, object code,
       documentation, design assets and other material that the Licensor
       publishes under this licence, including any part of it.

   1.3 "You" means the individual person who accepts this licence by
       copying, modifying or running the Software.

   1.4 "Permitted Circle" means You, the members of Your household, and
       Your friends, in each case only while they use the Software at no
       charge and not for any commercial purpose.

   1.5 "Personal Non-Commercial Use" means use by the Permitted Circle for
       private, personal purposes that do not earn, support or save money
       for any business, and for which nobody pays or receives anything of
       value.

   1.6 "Commercial Use" means any use that is not Personal Non-Commercial
       Use. It includes, without limitation:
       (a) use in, by or for a business, company, partnership, sole trader
           or other commercial undertaking, including use to read, send or
           manage that undertaking's email;
       (b) selling, renting or licensing the Software or access to it;
       (c) offering the Software, or a service substantially built on it,
           to others as a hosted, managed or "software as a service"
           offering, whether or not a fee is charged;
       (d) bundling, embedding or distributing the Software, or any part of
           it, in or with a product or service that is sold or that
           requires payment;
       (e) using the Software to provide any service to others for a fee;
           and
       (f) use by any organisation, whether or not it is run for profit.

   1.7 "Modification" means any change to, addition to, or work derived
       from the Software.

   1.8 "Contribution" means any code, documentation, design, issue text or
       other material that You submit to the Licensor for inclusion in the
       Software, for example through a pull request, patch, issue or email.

2. Copyright

   The Software is protected by copyright. Copyright (c) 2026 Sami Hindi.
   All rights not expressly granted in this licence are reserved by the
   Licensor.

3. Grant of rights

   3.1 Subject to the terms of this licence, the Licensor grants You a
       worldwide, royalty-free, non-exclusive, non-transferable and
       non-sublicensable licence to view, copy, modify and run the Software
       for Personal Non-Commercial Use only.

   3.2 This includes self-hosting the Software on hardware or hosting You
       control, and letting the rest of Your Permitted Circle use that
       self-hosted copy, provided nobody is charged for it.

   3.3 You may publish the source code of the Software and of Your
       Modifications, free of charge, provided that:
       (a) it is published under this licence and a complete copy of this
           licence accompanies it;
       (b) all copyright, licence and attribution notices are kept intact;
       (c) Your Modifications are clearly marked as changed; and
       (d) You do not use the Licensor's trademarks, as section 10 sets
           out.

   3.4 Anyone may compile the Software. You may distribute compiled builds
       of the Software or of Your Modifications to anyone, including through
       an app store, package registry or download service, provided that:
       (a) the builds are distributed free of charge;
       (b) they are distributed under this licence, with a complete copy of
           this licence and all copyright, licence and attribution notices
           intact;
       (c) the recipients' rights are those of this licence, so their use
           must also be Personal Non-Commercial Use;
       (d) builds that contain Modifications are clearly marked as changed;
           and
       (e) You do not present the builds as official Akatsuki releases or
           use the Licensor's trademarks, as section 10 sets out.

4. Commercial use is not granted

   4.1 This licence grants no rights for Commercial Use. All commercial
       rights in the Software are reserved by the Licensor.

   4.2 Commercial Use of any kind, including using the Software in or for a
       business, selling it, sublicensing it, offering it as a hosted
       service, bundling it into a paid product, or using it to provide a
       service for a fee, requires prior written permission from the
       Licensor. Permission is only valid if it is in writing and signed
       or sent by the Licensor.

   4.3 To ask for permission or a commercial licence, contact
       sami@samihindi.com.

   4.4 Using the official hosted service at akatsuki.vc (Akatsuki Pro) is
       governed by that service's own terms, not by this licence.

5. Notices

   Every copy of the Software, in whole or in part, must keep this licence
   and all copyright and attribution notices. You may not remove, hide or
   change them.

6. Contributions

   6.1 You keep the copyright in Your Contributions.

   6.2 By submitting a Contribution, You grant the Licensor and anyone the
       Licensor authorises a perpetual, worldwide, non-exclusive,
       royalty-free, irrevocable licence to use, copy, modify, publish,
       distribute, sublicense and relicense the Contribution, and works
       based on it, under any terms the Licensor chooses, including
       commercial and proprietary terms.

   6.3 You also grant the Licensor a perpetual, worldwide, non-exclusive,
       royalty-free, irrevocable licence under any patent You can license
       that is necessarily infringed by Your Contribution, alone or as
       combined with the Software, to make, use, sell, offer for sale,
       import and otherwise exploit it.

   6.4 You confirm that:
       (a) the Contribution is Your original work, or You otherwise have
           the right to grant these licences;
       (b) if Your employer or anyone else has rights in the Contribution,
           You have their permission to make it under these terms; and
       (c) the Contribution does not include material under terms that
           conflict with this section, unless You say so clearly when You
           submit it.

   6.5 To the extent the law allows, You waive, or agree not to assert,
       any moral rights in the Contribution against the Licensor and those
       the Licensor authorises.

   6.6 The Licensor has no obligation to accept, use or credit any
       Contribution.

7. Third-party components

   7.1 The Software uses and may include third-party components. Each one
       remains under its own licence, which is listed in THIRD_PARTY.md.
       This licence does not change, limit or replace those licences, and
       nothing in it restricts rights You have under them.

   7.2 In particular, the Convex backend is licensed under the Functional
       Source License, Version 1.1, Apache 2.0 Future License
       (FSL-1.1-Apache-2.0). If You run that backend yourself, You must
       follow its licence as well as this one.

8. Patents

   If You start legal proceedings alleging that the Software infringes a
   patent, all rights granted to You under this licence end on the date
   those proceedings are filed.

9. No warranty and limitation of liability

   9.1 The Software is provided "as is", without warranty of any kind,
       express or implied, including warranties of merchantability, fitness
       for a particular purpose, title and non-infringement.

   9.2 To the maximum extent the law allows, the Licensor is not liable for
       any claim, loss, damage or other liability, including loss of data,
       email or profit, arising from or in connection with the Software or
       its use, whether in contract, tort or otherwise.

   9.3 You are responsible for the security of any copy You run, and for
       the email accounts, credentials and data You connect to it.

10. Trademarks

    10.1 This licence grants no rights in the name "Akatsuki", the Akatsuki
         logo, the domain akatsuki.vc, or any other name, logo or mark of
         the Licensor.

    10.2 If You publish a Modification, You must give it a different name
         and logo. You may state truthfully that it is based on Akatsuki.

11. Termination

    11.1 If You breach this licence, Your rights under it end automatically.

    11.2 If it is Your first breach and You stop the breach and fix it
         within 30 days of receiving written notice from the Licensor, Your
         rights are reinstated. A later breach ends them permanently unless
         the Licensor reinstates them in writing.

    11.3 When Your rights end, You must stop using the Software and delete
         all copies in Your possession or control.

    11.4 Sections 2, 4, 6, 7, 9, 10 and 11 survive termination. Licences
         You granted under section 6 are irrevocable and survive in every
         case.

12. Other terms

    12.1 If any part of this licence is held unenforceable, the rest of it
         stays in effect, and the unenforceable part applies to the
         greatest extent the law allows.

    12.2 The Licensor may publish new versions of this licence. Software
         You received under this version stays under this version unless
         You choose to accept a later one.

    12.3 No failure or delay by the Licensor in enforcing any term waives
         that term.

13. Contact

    Permissions, commercial licences and questions about this licence:
    Sami Hindi, sami@samihindi.com