我们非常喜欢 MIT 许可证，特别是它的简单性，使其成为小型软件项目的完美许可证。
然而，随着 PSONO 的发展，我们花时间研究了与 MIT 兼容的其他开源许可证，但这些许可证可以更好地保护贡献者。这就是为什么我们将在下一个版本中切换到 Apache 许可证。
官方文档已经反映了这一变化。所有对 Psono 的贡献都将根据以下许可进行：
Copyright 2017 Sascha Pfeiffer
Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
此外，我们还增加了“开发者来源证明书”，熟悉 Linux 内核的人可能已经知道，它是贡献的一个要求。
Developer Certificate of Origin Version 1.1
Copyright (C) 2004, 2006 The Linux Foundation and its contributors. 1 Letterman Drive Suite D4700 San Francisco, CA, 94129
Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
Developer’s Certificate of Origin 1.1
By making a contribution to this project, I certify that:
(a) The contribution was created in whole or in part by me and I have the right to submit it under the open source license indicated in the file; or
(b) The contribution is based upon previous work that, to the best of my knowledge, is covered under an appropriate open source license and I have the right under that license to submit that work with modifications, whether created in whole or in part by me, under the same open source license (unless I am permitted to submit under a different license), as indicated in the file; or
(c) The contribution was provided directly to me by some other person who certified (a), (b) or (c) and I have not modified it.
(d) I understand and agree that this project and the contribution are public and that a record of the contribution (including all personal information I submit with it, including my sign-off) is maintained indefinitely and may be redistributed consistent with this project or the open source license(s) involved.
每个提交必须包含一个 DCO，格式如下：
Signed-off-by: Joe Smith
项目要求使用的名称必须是真实姓名。不接受匿名贡献者或使用假名的贡献者。
在 git 配置中设置你的 user.name 和 user.email，然后始终使用 -s 或 --signoff 标志，将“Signed-off-by 行”添加到提交消息的末尾。
