docs/source/contributor-guide/communication.md

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# Community Communication

We welcome participation from everyone and encourage you to join us, ask
questions, and get involved.
All participation in the Apache DataFusion project is governed by the
Apache Software Foundation's [code of
conduct](https://www.apache.org/foundation/policies/conduct.html).

## GitHub

The primary means of communication is the
[GitHub repository](https://github.com/apache/datafusion) in the form of issues, discussions, and Pull Requests.
Our repository is open to everyone. We encourage you to
participate by reporting issues, asking questions, and contributing code.

## Chat

We also use the Discord and Slack platforms for lower latency, informal discussions and coordination.
These are great places to
meet other members of the community, ask questions, and brainstorm ideas.
However, to ensure technical discussions are archived and accessible to everyone,
all technical designs are recorded and formalized in GitHub issues.

### Discord

Historically, the most active discussion forum has been the [Arrow Rust Discord
server][discord-link] which has specific channels for Arrow, DataFusion, and
DataFusion subprojects such as Ballista, Comet, Python, etc.
DataFusion specific channels are prefixed with the `#datafusion-` tag.
We recommend new users join this server for real-time discussions with the community.

### Slack

Some of the community also uses the [ASF Slack workspace] for discussions. This
has historically been much less active than the Discord server.
Unfortunately, due to spammers, the ASF Slack workspace [requires an invitation]
to join. We are happy to invite any community member -- please ask for an
invitation in the Discord server.

[asf slack workspace]: https://the-asf.slack.com/
[requires an invitation]: https://s.apache.org/slack-invite

In Slack, we use these channels:

- `#arrow`
- `#arrow-rust`
- `#datafusion`
- `#datafusion-ballista`
- `#datafusion-comet`
- `#datafusion-python`

### Job Board

There are plenty of opportunities to work with DataFusion advertised on the
#hiring channel on the [Arrow Rust Discord Server][discord-link].
Please feel free to post links to DataFusion related jobs there.

## Mailing Lists

Like other Apache projects, we use [mailing lists] for certain purposes, most
importantly release coordination and announcing new committers and PMC members.
Other than these processes, most DataFusion mailing list traffic will link to a GitHub issue or PR where
the actual discussion occurs. The project mailing lists are:

- [`dev@datafusion.apache.org`](mailto:dev@datafusion.apache.org): the main
  mailing list for release coordination and other project-wide discussions. Links:
  [archives](https://lists.apache.org/list.html?dev@datafusion.apache.org),
  [subscribe](mailto:dev-subscribe@datafusion.apache.org),
  [unsubscribe](mailto:dev-unsubscribe@datafusion.apache.org)
- `github@datafusion.apache.org`: read-only mailing list that receives all GitHub notifications for the project. Links:
  [archives](https://lists.apache.org/list.html?github@datafusion.apache.org)
- `commits@datafusion.apache.org`: read-only mailing list that receives all GitHub commits for the project. Links:
  [archives](https://lists.apache.org/list.html?commits@datafusion.apache.org)
- `private@datafusion.apache.org`: private mailing list for PMC members. This list has very little traffic, almost exclusively discussions on growing the committer and PMC membership. Links:
  [archives](https://lists.apache.org/list.html?private@datafusion.apache.org)

[mailing lists]: https://www.apache.org/foundation/mailinglists
[discord-link]: https://discord.gg/Qw5gKqHxUM