=====================
Contributing to MOPAC
=====================

MOPAC is an open source project and, as such, contributions are welcome and appreciated.
The standard, minimal legal stipulations apply: all contributions must be provided under
the Apache 2.0 license and all contributors must agree to the DCO by using their real name
and a valid email address in their git commit statements.

How to contribute
=================

Please create a GitHub `Issue <https://github.com/openmopac/mopac/issues/new>`_ for bug
reports and feature requests.

The preferred method of code contribution is to fork the project on
`GitHub <https://github.com/openmopac/mopac>`_, make your changes in a feature branch
starting from the main branch, and then create a pull request. Contributions from outside
of version control will be considered, but they are not preferred. MOPAC does not presently
have strong stylistic or structural requirements, but contributions are encouraged to
conform to the existing codebase as much as possible.

Open pull requests are also welcome, where a pull request is made before a contribution
is ready to be merged, to open up an active dialogue between the core developers and the
contributor about details of the contribution in development. This mode of operation is
particularly useful when a pull request is linked with an issue articulating a problem
that the pull request intends to solve.

While not a strict requirement, code contributions should pass all available tests,
either as they are or with their reference outputs adjusted with an explanation
for why they needed to be adjusted. Contributions may be delayed or rejected if they
fail a test in a meaningful way that is not straightforward to correct.

Historically, major feature contributions to MOPAC were required to be preceded by a journal
publication to maintain clear attribution. While this is no longer necessary for open-source
software developed under automated version control, it is still encouraged.

Major feature contributions should include new tests that cover standard use cases of the
new feature, and corresponding additions to the manual [https://openmopac.github.io],
particularly if new keywords are introduced.

What to contribute
==================

Many types of contributions are welcome:

- bug reports (preferably with a representative example)
- new tests
- new features
- performance improvements
- code quality improvements
- feature requests

Developer Certificate of Origin
===============================

Contributors to MOPAC are assumed to agree with the Linux Foundation's 
`Developer Certificate of Origin <https://developercertificate.org/>`::

    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.
