The MIT License
Copyright © 2015-2017, EnduraCode LLC
Portions Copyright © 2001-2015, William Gross and Greg Smalter and Sam Rueby
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Why do we use this license?
The MIT License is a permissive open-source license. This essentially means that companies can build software on top of this code and make a profit, either by directly selling their software or by making it a part of a larger offering.
The other license category is called copyleft, and includes licenses such as the GNU General Public License (GPL), and the lesser-known GNU Affero General Public License (AGPL). If we had chosen one of these, companies who build software on top of EWL would need to release their code under the same license to their users. This would obliterate the market value of their code, a conclusion that is clear with a thought experiment. Imagine company X decides to charge $1,000 for software built on EWL. As soon as they make their first sale, and get their first user, this user is entitled to the code, and has the freedom to give it to anyone, at any price, including $0.
We released EWL as a gift, and if companies can use it to make money, even by competing with us, we do not want to interfere. We make our living by writing code and we don’t want to deny others that ability.
We could have dual-licensed the code, by releasing it under a copyleft license, and then selling commercial licenses to any company that wants to build on it for profit. This is a common model. The appeal is that “if they make money, we’ll make some too.” But from the market perspective, in which the copyleft license is useless, this is essentially proprietary software. Customers would be at our mercy, with only a “take it or leave it” choice. If they disagreed with changes we were making to the code, or wanted to make their own enhancements, they would not be able to part ways with us and fork the code in their own direction. Dual-licensing would be a power grab on our part, a way to keep ourselves at the center of the project even if someone else could do a better job.
Our permissive license does not force EWL improvements to be released back into the community. But companies are likely to give back their changes anyway to avoid the ever-worsening merge situation caused by maintaining a fork of the code while compelling features continue to be added to our version.