dev/PROJECT_GUIDELINES.md

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- [Adding a Committer or PMC Member](#adding-a-committer-or-pmc-member)
- [Airflow Improvement Proposals (AIPs)](#airflow-improvement-proposals-aips)
- [Support for Airflow 1.10.x releases](#support-for-airflow-110x-releases)
- [Support for Backport Providers](#support-for-backport-providers)
- [Release Guidelines](#release-guidelines)

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This document describes all the guidelines that have been agreed upon by the committers and PMC
members on the mailing list.

## Adding a Committer or PMC Member

[COMMITTERS.rst](../COMMITTERS.rst) contains the guidelines for adding a new Committer and promoting an existing
Committer to a PMC member.

## Airflow Improvement Proposals (AIPs)

When voting on AIPs, both PMC members and committers have a binding vote.
([Link](https://lists.apache.org/thread.html/ra22cb7799e62e451fc285dee29f9df1eb17c000535ca2911c322c797%40%3Cdev.airflow.apache.org%3E))

## Support for Airflow 1.10.x releases

The Airflow 1.10.x series will be supported for six months (June 17, 2021) from Airflow 2.0.0
release date (Dec 17, 2020). Specifically, only 'critical fixes' defined as fixes to bugs
that take down Production systems, will be backported to 1.10.x until June 17, 2021.

## Support for Backport Providers

Backport providers within 1.10.x, are not released any more, as of (March 17, 2021).

## Release Guidelines

### Apache Airflow (core)

- Follow Semantic Versioning ([SEMVER](https://semver.org/))
- Changing the version of dependency should not count as breaking change

### Providers

#### Batch & Ad-hoc Releases

- Release Manager would default to releasing Providers in Batch
- If there is a critical bug that needs fixing in a single provider, an ad-hoc release for
that provider will be created

#### Frequency

We will release all providers **every month** (Mostly first week of the month)

**Note**: that it generally takes around a week for the vote to pass even
though we have 72 hours minimum period

#### Doc-only changes

When provider(s) has doc-only changes during batch-release, we
will not release that provider with a new version. As unliked the
actual releases, our doc releases are mutable.

So, we will simply tag that those providers with `*-doc1`, `*-doc2` tags in the repo
to release docs for it.