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Rosetta::Copying - Matters of ownership, licensing, contributions


This document is about copyright issues concerning the Rosetta DBMS framework, both as they are now, and how I anticipate them being in the future. These may very well be intuitive, but I'll follow the principle of least surprise and spell them out anyway, so that no one is surprised later on.


The inner core of the Rosetta framework, defined as the smallest number of components that all users of Rosetta require, are these Perl files; each one depends on all of the others listed above it:

    * /lib/Rosetta/
    * /lib/

Note that at least one additional file, whether from myself or a third party, is required to fulfil the role of an "Engine", in order to use lib/ at all, meaning the actual minimal count is 3.

(The inner core also has an external dependency on my LGPL-licensed Locale::KeyedText, that is also required to use it, but that is not actually part of the Rosetta framework itself.)

Both and are part of a common 'Rosetta' distribution on CPAN, but can actually be used independently from; they are bundled mainly for easier co-development, and that using them together is the most common case. Engines are distributed separately, except for a fully functional "Example". Each distribution may have additional files that are tied to the named file, because they serve as documentation or examples or tests or localization data for it, and the whole collection in the distribution is considered a single unit as far as ownership and licensing goes, unless explicitly stated otherwise therein.

The Rosetta framework includes a comprehensive shared test suite to ensure the correctness of itself and of any Engine components, its outer core, which is comprised of these Perl files:

    * /lib/Rosetta/
    * /lib/Rosetta/Engine/

While not essential to the daily use of Rosetta, they are very important to the framework at large and are strongly recommended to be used at installation time. The can be used to test any Engine, and is included in the distribution; it is expected that there never will be a third party substitution for it. The is also included in the distribution and implements a standalone Engine for testing in the first place, so it has a working example of expected behaviour; it is anticipated that you will substitute another Engine (typically third party) for Example by production time. Neither depends on anything specific but the inner core.

Any other independent distributions that exist and use Rosetta, whether made by myself or third parties, are not part of the Rosetta framework core, but constitute extensions.


Presently, all of the Rosetta framework core files are owned entirely by myself, and I have complete freedom to use and license them under any terms of my choosing; there are no co-owners to consult.

Presently, all of the Rosetta framework core files have been created and maintained entirely by myself, both code and documentation, save for small amounts of casual assistence by other people. This consists mainly of providing me advice in discussions that went to improve Rosetta, or in correcting minor code details or typos (such as to remain consistent with a Perl 6 language spec change). Exceptions are specifically mentioned.

In accordance with common sense, I maintain that none of the assistence received to date, save any specifically mentioned, is enough to warrant partial ownership of affected portions of Rosetta to the other people, and so they remain entirely mine.

Likewise, I disclaim any possible ownership over portions of other peoples' projects for whom my contribution was minor and casual, and even with more major contributions, I disclaim any ownership interest in them, unless explicitly stated otherwise.

In the future, I am willing that the ownership of some of Rosetta's extensions that I create can be shared with or transferred to other people for various reasons, but I am also not willing to share or relinquish full ownership of some other components at all.

Specifically, I wish to retain full ownership and control of the inner and outer cores of Rosetta, namely:

    * /lib/Rosetta/
    * /lib/
    * /lib/Rosetta/
    * /lib/Rosetta/Engine/

Whereas, I am willing to share or transfer ownership over any or all of the various Rosetta extensions, if other people contribute a lot to them and/or are willing and able to become their primary maintainers.


All components of the Rosetta framework that I own, particularly the core, are now and forever available under at least one free and open source license. This grants all users the right to use it for any purpose, to make modifications, and to redistribute both the pristine and modified versions. The specific license terms may differ for each component, and are specified in that component's documentation.

This is a summary of their licensing terms, but what is written in the components themselves takes precedence.

Each core distribution is licensed under the GPL version 2.0 or later, with a linking exception granted for other software components whose own licenses qualify as free software according to; a system incorporating such components and any core Rosetta components can be distributed where the Rosetta components are subject to the GPL and the other such components to their licenses.

That is, any third party component that links to Rosetta is required to be distributed under the GPL unless at least one of the following conditions is met:

1. It is distributed separately from Rosetta, listing Rosetta as an *external* dependency, and the end user installs the third party component and Rosetta separately. This is what the plain GPL allows.

2. The third party component can bundle Rosetta with it, but that it's own license qualifies it as free software. This is what my exception permits but vanilla GPL does not.

3. I have sold them a proprietary license allowing it.

All components of the Rosetta framework that I own are also available for sale under a proprietary license, for those people that want to extricate themselves from the GPL. This is one method of generating income from the Rosetta framework that I will have exclusive to myself, in addition to the methods that GPL licensing provides to everyone, such as support contracts and sponsored improvements. The same dual-license business practice is also used effectively by MySQL AB and others.

Note that I plan to relicense these same components explicitly under the GPL version 3 (or later) when that GPL version is finalized, barring any unexpected difficulties. The first GPL v3 draft, published 2006.01.16 at, already looks good. And it natively includes terms like my linking exception to v2 for other free software.

I have no intention of broadly releasing Rosetta under any open source license but the GPL, such as the Perl or Artistic or BSD licenses, because that would open a large hole in the dual-licensing plan. However, workable and limited scope arrangements can be made on a case by case basis.

All extensions that I create to the Rosetta framework whose sole purpose is to enable other modules or applications on top of Rosetta, such as Tangram or DBIx::Class or Bricolage, will be licensed under the same terms as those components being enabled.

For example, "DBIx::Class::Storage::Rosetta is free software and is licensed under the same terms as DBIx::Class itself".

A primary advantage of this approach is that the enabled component can choose to refactor itself by moving code from my glue module to itself, without impacting its licensing implications. It also makes conceptual sense, since the glue is more part of the enabled component than Rosetta.


I welcome and encourage contributions towards improving Rosetta from anyone and at any time, big or small, and for any part of the system.

Considering Rosetta's heavily componentized design, some improvements are best included in the core, and others are best done as externally distributed extensions. As Rosetta matures, changes to extensions should become the more common way to extend it than modifying the core is, since a mature core should readily support a wide variety of extensions.

In the case of extensions that you write and distribute separately, you retain ownership of them as usual.

If your contribution fits best inside one of my modules and is non-trivial, then you would normally retain ownership of that contribution unless you grant said ownership to me.

In the case of inner or outer core modules, I will require the transfer of ownership for your contribution, so I can maintain full ownership of said core modules. Alternately, I would expect a perpetual grant over the contribution to use and sublicense it in any way I choose, so that it is as if I owned it, but you would then also retain ownership to use it yourself.

If you refuse the transfer or grant, then I will not accept the contribution into the module, or may possibly rewrite it instead to make it my own work, in which case the contribution would effectively be 'advice'.

As an exception to the above, material changes to a core module that are distributed independently as a patch will remain yours.

In a worst case scenario, you are always allowed to fork Rosetta, and have shared ownership in your alternate version, though I would hope that a fork would never happen.


I created Rosetta in the hope that it would be greatly useful to and be used by a lot of people, and lead to positive change in society. Releasing it free should take care that it serves this purpose over the long term. But I also strive that it can contribute to my ability to earn a living over the long term. Hopefully the policies I have laid out are fair and acceptable to everyone.


Go to Rosetta for the majority of distribution-internal references, and Rosetta::SeeAlso for the majority of distribution-external references.


Darren R. Duncan (


This file is part of the Rosetta DBMS framework.

Rosetta is Copyright (c) 2002-2006, Darren R. Duncan.

See the LICENCE AND COPYRIGHT of Rosetta for details.


The ACKNOWLEDGEMENTS in Rosetta apply to this file too.

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