Merge branch 'docs/30141-improve-contributing-guide' into 'master'

Resolve "Combine all GitLab workflow documentation to CONTRIBUTING.md"

Closes #30141

See merge request !10991

PROCESS.md

-# GitLab Contributing Process
+## GitLab Core Team & GitLab Inc. Contribution Process
+
+---
+
+<!-- START doctoc generated TOC please keep comment here to allow auto update -->
+<!-- DON'T EDIT THIS SECTION, INSTEAD RE-RUN doctoc TO UPDATE -->
+**Table of Contents**  *generated with [DocToc](https://github.com/thlorenz/doctoc)*
+
+- [Purpose of describing the contributing process](#purpose-of-describing-the-contributing-process)
+- [Common actions](#common-actions)
+  - [Merge request coaching](#merge-request-coaching)
+- [Assigning issues](#assigning-issues)
+- [Be kind](#be-kind)
+- [Feature freeze on the 7th for the release on the 22nd](#feature-freeze-on-the-7th-for-the-release-on-the-22nd)
+  - [Between the 1st and the 7th](#between-the-1st-and-the-7th)
+  - [On the 7th](#on-the-7th)
+  - [After the 7th](#after-the-7th)
+- [Release retrospective and kickoff](#release-retrospective-and-kickoff)
+  - [Retrospective](#retrospective)
+  - [Kickoff](#kickoff)
+- [Copy & paste responses](#copy--paste-responses)
+  - [Improperly formatted issue](#improperly-formatted-issue)
+  - [Issue report for old version](#issue-report-for-old-version)
+  - [Support requests and configuration questions](#support-requests-and-configuration-questions)
+  - [Code format](#code-format)
+  - [Issue fixed in newer version](#issue-fixed-in-newer-version)
+  - [Improperly formatted merge request](#improperly-formatted-merge-request)
+  - [Inactivity close of an issue](#inactivity-close-of-an-issue)
+  - [Inactivity close of a merge request](#inactivity-close-of-a-merge-request)
+  - [Accepting merge requests](#accepting-merge-requests)
+  - [Only accepting merge requests with green tests](#only-accepting-merge-requests-with-green-tests)
+  - [Closing down the issue tracker on GitHub](#closing-down-the-issue-tracker-on-github)
+
+<!-- END doctoc generated TOC please keep comment here to allow auto update -->
+
+---
 
 ## Purpose of describing the contributing process
 
-Below we describe the contributing process to GitLab for two reasons. So that
-contributors know what to expect from maintainers (possible responses, friendly
-treatment, etc.). And so that maintainers know what to expect from contributors
-(use the latest version, ensure that the issue is addressed, friendly treatment,
-etc.).
+Below we describe the contributing process to GitLab for two reasons:
+
+1. Contributors know what to expect from maintainers (possible responses, friendly
+  treatment, etc.)
+1. Maintainers know what to expect from contributors (use the latest version,
+  ensure that the issue is addressed, friendly treatment, etc.).
 
 - [GitLab Inc engineers should refer to the engineering workflow document](https://about.gitlab.com/handbook/engineering/workflow/)
 
 ## Common actions
 
-### Issue triaging
-
-Our issue triage policies are [described in our handbook]. You are very welcome
-to help the GitLab team triage issues. We also organize [issue bash events] once
-every quarter.
-
-The most important thing is making sure valid issues receive feedback from the
-development team. Therefore the priority is mentioning developers that can help
-on those issues. Please select someone with relevant experience from
-[GitLab team][team]. If there is nobody mentioned with that expertise
-look in the commit history for the affected files to find someone. Avoid
-mentioning the lead developer, this is the person that is least likely to give a
-timely response. If the involvement of the lead developer is needed the other
-core team members will mention this person.
-
-[described in our handbook]: https://about.gitlab.com/handbook/engineering/issues/issue-triage-policies/
-[issue bash events]: https://gitlab.com/gitlab-org/gitlab-ce/issues/17815
-
 ### Merge request coaching
 
 Several people from the [GitLab team][team] are helping community members to get
@@ -37,12 +55,6 @@ their contributions accepted by meeting our [Definition of done][done].
 
 What you can expect from them is described at https://about.gitlab.com/jobs/merge-request-coach/.
 
-## Workflow labels
-
-Labelling issues is described in the [GitLab Inc engineering workflow].
-
-[GitLab Inc engineering workflow]: https://about.gitlab.com/handbook/engineering/workflow/#labelling-issues
-
 ## Assigning issues
 
 If an issue is complex and needs the attention of a specific person, assignment is a good option but assigning issues might discourage other people from contributing to that issue. We need all the contributions we can get so this should never be discouraged. Also, an assigned person might not have time for a few weeks, so others should feel free to takeover.
@@ -146,6 +158,29 @@ release should have the correct milestone assigned _and_ have the label
 Merge requests without a milestone and this label will
 not be merged into any stable branches.
 
+## Release retrospective and kickoff
+
+### Retrospective
+
+After each release, we have a retrospective call where we discuss what went well,
+what went wrong, and what we can improve for the next release. The
+[retrospective notes] are public and you are invited to comment on them.
+If you're interested, you can even join the
+[retrospective call][retro-kickoff-call], on the first working day after the
+22nd at 6pm CET / 9am PST.
+
+### Kickoff
+
+Before working on the next release, we have a
+kickoff call to explain what we expect to ship in the next release. The
+[kickoff notes] are public and you are invited to comment on them.
+If you're interested, you can even join the [kickoff call][retro-kickoff-call],
+on the first working day after the 7th at 6pm CET / 9am PST..
+
+[retrospective notes]: https://docs.google.com/document/d/1nEkM_7Dj4bT21GJy0Ut3By76FZqCfLBmFQNVThmW2TY/edit?usp=sharing
+[kickoff notes]: https://docs.google.com/document/d/1ElPkZ90A8ey_iOkTvUs_ByMlwKK6NAB2VOK5835wYK0/edit?usp=sharing
+[retro-kickoff-call]: https://gitlab.zoom.us/j/918821206
+
 ## Copy & paste responses
 
 ### Improperly formatted issue

doc/development/code_review.md

 # Code Review Guidelines
 
+## Getting your merge request reviewed, approved, and merged
+
+There are a few rules to get your merge request accepted:
+
+1. Your merge request should only be **merged by a [maintainer][team]**.
+  1. If your merge request includes only backend changes [^1], it must be
+    **approved by a [backend maintainer][team]**.
+  1. If your merge request includes only frontend changes [^1], it must be
+    **approved by a [frontend maintainer][team]**.
+  1. If your merge request includes frontend and backend changes [^1], it must
+    be **approved by a [frontend and a backend maintainer][team]**.
+1. To lower the amount of merge requests maintainers need to review, you can
+  ask or assign any [reviewers][team] for a first review.
+  1. If you need some guidance (e.g. it's your first merge request), feel free
+    to ask one of the [Merge request coaches][team].
+  1. The reviewer will assign the merge request to a maintainer once the
+    reviewer is satisfied with the state of the merge request.
+
+## Best practices
+
 This guide contains advice and best practices for performing code review, and
 having your code reviewed.
 
@@ -12,7 +32,7 @@ of colleagues and contributors. However, the final decision to accept a merge
 request is up to one the project's maintainers, denoted on the
 [team page](https://about.gitlab.com/team).
 
-## Everyone
+### Everyone
 
 - Accept that many programming decisions are opinions. Discuss tradeoffs, which
   you prefer, and reach a resolution quickly.
@@ -31,8 +51,11 @@ request is up to one the project's maintainers, denoted on the
 - Consider one-on-one chats or video calls if there are too many "I didn't
   understand" or "Alternative solution:" comments. Post a follow-up comment
   summarizing one-on-one discussion.
+- If you ask a question to a specific person, always start the comment by
+  mentioning them; this will ensure they see it if their notification level is
+  set to "mentioned" and other people will understand they don't have to respond.
 
-## Having your code reviewed
+### Having your code reviewed
 
 Please keep in mind that code review is a process that can take multiple
 iterations, and reviewers may spot things later that they may not have seen the
@@ -50,11 +73,12 @@ first time.
 - Extract unrelated changes and refactorings into future merge requests/issues.
 - Seek to understand the reviewer's perspective.
 - Try to respond to every comment.
+- Let the reviewer select the "Resolve discussion" buttons.
 - Push commits based on earlier rounds of feedback as isolated commits to the
   branch. Do not squash until the branch is ready to merge. Reviewers should be
   able to read individual updates based on their earlier feedback.
 
-## Reviewing code
+### Reviewing code
 
 Understand why the change is necessary (fixes a bug, improves the user
 experience, refactors the existing code). Then:
@@ -69,12 +93,19 @@ experience, refactors the existing code). Then:
   someone else would be confused by it as well.
 - After a round of line notes, it can be helpful to post a summary note such as
   "LGTM :thumbsup:", or "Just a couple things to address."
+- Assign the merge request to the author if changes are required following your
+  review.
+- Set the milestone before merging a merge request.
 - Avoid accepting a merge request before the job succeeds. Of course, "Merge
   When Pipeline Succeeds" (MWPS) is fine.
 - If you set the MR to "Merge When Pipeline Succeeds", you should take over
   subsequent revisions for anything that would be spotted after that.
+- Consider using the [Squash and
+  merge][squash-and-merge] feature when the merge request has a lot of commits.
+
+[squash-and-merge]: https://docs.gitlab.com/ee/user/project/merge_requests/squash_and_merge.html#squash-and-merge
 
-## The right balance
+### The right balance
 
 One of the most difficult things during code review is finding the right
 balance in how deep the reviewer can interfere with the code created by a
@@ -100,7 +131,7 @@ reviewee.
   tomorrow. When you are not able to find the right balance, ask other people
   about their opinion.
 
-## Credits
+### Credits
 
 Largely based on the [thoughtbot code review guide].