Author of marshmallow here. We need your help with marshmallow 3.0

Hello! I am the author of [marshmallow](https://github.com/marshmallow-code/marshmallow). I'm here to ask for your help
with development on marshmallow 3.0, which is underway!

**What is marshmallow?**

marshmallow is a library for validating, deserializing, and serializing data. It's most commonly used to validate request input, deserialize to models, then serialize models to response data.

As web apps are increasingly API-driven, marshmallow has become a popular tool in the Flask ecosystem.

**How can you help?**

There's many ways to contribute!

Contribute brainpower:

* Comment on marshmallow's open issues, especially those labeled
[feedback welcome](https://github.com/marshmallow-code/marshmallow/issues?q=is%3Aopen+is%3Aissue+label%3A%22feedback+welcome%22)
* Open an issue with an idea to improve the API.

Contribute code

* Open a PR to address any of the open issues, especially those labeled
[help wanted](https://github.com/marshmallow-code/marshmallow/issues?utf8=%E2%9C%93&q=is%3Aissue+is%3Aopen+label%3A%22help+wanted%22+). Check out the [Contributing Guidelines](https://marshmallow.readthedocs.io/en/latest/contributing.html) to see how to get started.
* Upgrade your codebase to marshmallow 3 beta. See the [upgrading
guide](https://marshmallow.readthedocs.io/en/latest/upgrading.html#upgrading).

Contribute financially:

* Contribute financially on our [open collective](https://opencollective.com/marshmallow).
* If you're using marshmallow at your company, ask them to [become a sponsor](https://opencollective.com/marshmallow#sponsor)

Thank you to everyone who decides to contribute. It means a lot to the marshmallow team.