= Contributing

The `Substrate` project is an **OPENISH Open Source Project**

== What?

Individuals making significant and valuable contributions are given commit-access to a project to contribute as they see fit. A project is more like an open wiki than a standard guarded open source project.

== Rules

There are a few basic ground-rules for contributors (including the maintainer(s) of the project):

. **No `--force` pushes** or modifying the Git history in any way. If you need to rebase, ensure you do it in your own repo.
. **Non-master branches**, prefixed with a short name moniker (e.g. `gav-my-feature`) must be used for ongoing work.
. **All modifications** must be made in a **pull-request** to solicit feedback from other contributors.
. A pull-request *must not be merged until CI* has finished successfully.
. Contributors should adhere to the https://wiki.parity.io/Substrate-Style-Guide[house coding style].


== Merge Process

Merging pull requests once CI is successful:

. A PR needs to be reviewed and approved by project maintainers unless:
	- it does not alter any logic (e.g. comments, dependencies, docs), then it may be tagged https://github.com/paritytech/substrate/pulls?utf8=%E2%9C%93&q=is%3Apr+is%3Aopen+label%3AA2-insubstantial[`insubstantial`] and merged by its author once CI is complete.
  - it is an urgent fix with no large change to logic, then it may be merged after a non-author contributor has approved the review once CI is complete.

. Once a PR is ready for review please add the https://github.com/paritytech/substrate/pulls?q=is%3Apr+is%3Aopen+label%3AA0-pleasereview[`pleasereview`] label. Generally PRs should sit with this label for 48 hours in order to garner feedback. It may be merged before if all relevant parties had a look at it.
. PRs that break the external API must be tagged with https://github.com/paritytech/substrate/labels/B2-breaksapi[`breaksapi`], when it changes the SRML or consensus of running system with https://github.com/paritytech/substrate/labels/B3-breaksconsensus[`breaksconsensus`]
. No PR should be merged until all reviews' comments are addressed.

*Reviewing pull requests*:

When reviewing a pull request, the end-goal is to suggest useful changes to the author. Reviews should finish with approval unless there are issues that would result in:

. Buggy behaviour.
. Undue maintenance burden.
. Breaking with house coding style.
. Pessimisation (i.e. reduction of speed as measured in the projects benchmarks).
. Feature reduction (i.e. it removes some aspect of functionality that a significant minority of users rely on).
. Uselessness (i.e. it does not strictly add a feature or fix a known issue).

*Reviews may not be used as an effective veto for a PR because*:

. There exists a somewhat cleaner/better/faster way of accomplishing the same feature/fix.
. It does not fit well with some other contributors' longer-term vision for the project.

== Helping out

We use https://github.com/paritytech/substrate/labels[labels] to manage PRs and issues and communicate state of a PR. Please familiarize yourself with them. Further more we are organising issues in https://github.com/paritytech/substrate/milestones[milestones]. Best way to get started is to a pick a ticket from the current milestone tagged https://github.com/paritytech/substrate/issues?q=is%3Aissue+is%3Aopen+label%3AQ2-easy[`easy`] or https://github.com/paritytech/substrate/issues?q=is%3Aissue+is%3Aopen+label%3AQ3-medium[`medium`] and get going or https://github.com/paritytech/substrate/issues?q=is%3Aissue+is%3Aopen+label%3AX1-mentor[`mentor`] and get in contact with the mentor offering their support on that larger task.  

== Releases

Declaring formal releases remains the prerogative of the project maintainer(s).

== Changes to this arrangement

This is an experiment and feedback is welcome! This document may also be subject to pull-requests or changes by contributors where you believe you have something valuable to add or change.

== Heritage

These contributing guidelines are modified from the "OPEN Open Source Project" guidelines for the Level project: https://github.com/Level/community/blob/master/CONTRIBUTING.md