Licensing

We would like our the tools and their technology to be used by as many developers as possible, while at the same time making sure that the tools evolve and improve.

To that end, the Data Modelling tools (DMT) and their documentation are offered in a dual licensing mode:

- If you are developing proprietary and/or commercial software with the tools, you must purchase a Commercial Developer License. This license of the tools is for developers who do not want to share the source code they develop and/or do not want to comply with the terms of the GNU General Public License version 2.1.

- If, on the other hand...

(a) you are in compliance with the terms of the GNU General Public License version 2.1 (that is, amongst other requirements, you will share your complete source code with anyone who asks for it)
AND
(b) you are developing non-commercial applications

...then you can use the tools for free, with their code governed by the GNU General Public License version 2.1.

By purchasing a Commercial Developer License, you are entitled to one year's worth of premium technical support, with same-working-day access (via e-mail and instant messaging) to the developers behind the tools, automatic updates with state-of-the-art new features, etc.

The differences are summarized in the table below:

License type:	Commercial	GPL
License cost	License fee charged	No license fee
Must provide access to all source code changes back to Semantix	No, modifications can be "closed" to your own system	Yes, all source code of your system must be accessible to everyone
Can create proprietary applications	Yes, no source code needs to be disclosed	No, applications are subject to the GPL and all source code must be made available
Support	Yes, 12 months of premium technical support (same-workday access via e-mail and instant messaging)	None, but can be purchased separately
Charge for runtimes	None	None, but all your systems's source code must be available
Custom, mission-specific additions to the tools	Yes^*	None

This dual licensing scheme is followed by many other businesses (see licenses of Nokia's QT, Oracle/SUN's MySQL, etc). It guarantees the perennity (longevity) of the code, since all the source code of the tools is visible to everyone, while retaining the business case for the efforts behind supporting them - since clients can purchase premium support.

^{*Charges for additions vary, depending on request complexity.}