What license is used for VisualEiffel?
We release VisualEiffel with a dual license strategy, as it is common practice in some open-source projects like mozilla, openoffice and others. The compiler and libraries of VE-OS (the open-source variant of VisualEiffel) are released under the Gnu General Public License (GPL), which is widely regarded as the "gold standard" for open-source licenses.
In what ways can I use VE-OS?
You can freely use VE-OS for any purpose except to produce proprietary software applications. The kernel library of VE-OS is GPL-licensed, and every application produced by VE-OS depends on the kernel library. Therefore, applications produced using VE-OS can only be distributed under the GPL. Specifically, you must also distribute the source code.
What if I want to produce proprietary software?
If you want to produce proprietary software, you should purchase Visual Eiffel Enterprise. The license for Visual Eiffel Enterprise allows you to distribute proprietary software. Visual Eiffel Enterprise is also eligible for enhanced support offerings.
Apart from the licensing, are there any other differences between VE-OS and Visual Eiffel Enterprise?
Yes. Although the compiler, Workbench and and libraries are the same, the Display Machine delivered with Visual Eiffel Enterprise is not. In addition, the Enterprise edition contains Libraries which are not licensed under the GPL.
Can I use VE-OS to develop in-house commercial applications?
No - this is explicitely forbidden by the Visual Eiffel License. Even it this would not be the case, the GPL wouldn't allow you to do this. Those in-house commercial applications would themselves be subject to the GPL, and you would have to make the source code available (to anyone that you distribute the binary to). That person could then redistribute the application (under the GPL), which might put them in conflict with their terms of employment.
Can I modify the VE-OS compiler or libraries?
Yes. If you distribute your modifications, you must distribute them under the GPL.
Can I port VE-OS to a new operating system?
Yes. If you distribute your port, you must distribute it under the GPL.
Can I contribute my enhancements back into VE-OS?
Yes, we welcome contributions. But Object Tools can only accept your code into our Visual Eiffel codebase if you give us permission to include the code in both of our editions - Open-Source and Enterprise. We will ask you to confirm this by email or webform before we can accept your patch.
Is the Display Machine interface builder also open-sourced?
No. Display Machine is available for free, but the source code is not included. The only limitation of the free version is that you cannot set the window title (it displays always "DisplaMachine"). Display Machine delivered with Visual Eiffel Enterprise does not have this limitation.
Can I use VE-OS in order to learn and to teach programming ?
Yes: Using Visual Eiffel in order to teach or to learn programming technology can be done under the GPL license unless programs developed are used for commercial purposes as described above.
Whats about Non-Profits and Academic Institutions ?
If you represent a non-profit organization or an academic institution, we recommend you publish your application as an open source / free software project using the GPL license. Thereby, you are free to use Visual Eiffel free of charge under the GPL license. If you have strong reasons to not publish your application in accordance with the GPL, you should purchase commercial licenses.
I use VE only for private, non commercial applications
If you are a private individual you are free to use Visual Eiffel for your personal applications (not those of your employer) as long as you do not distribute them. If you distribute them, you must make a decision between the Commercial License and the GPL.