"Fossies" - the Fresh Open Source Software Archive

Member "jenkins-jenkins-2.249.3/docs/MAINTAINERS.adoc" (4 Nov 2020, 28726 Bytes) of package /linux/misc/jenkins-jenkins-2.249.3.tar.gz:


As a special service "Fossies" has tried to format the requested text file into HTML format (style: standard) with prefixed line numbers. Alternatively you can here view or download the uninterpreted source code file.

    1 :toc:
    2 :toclevels: 3
    3 
    4 = Documentation for core maintainers
    5 
    6 toc::[]
    7 
    8 Jenkins core is a central component of the project which serves millions of users, and it is critical to maintain it in a good shape.
    9 We want to ensure quality of the integrated changes and continuity of the project,
   10 and hence the Jenkins core pull request review and merge process is more sophisticated than for the majority of plugins.
   11 
   12 == Scope of the document
   13 
   14 This document applies to the following components:
   15 
   16 * Jenkins core
   17 * Jenkins modules
   18 * Libraries included into the Jenkins core
   19 * Core components like Winstone, Executable WAR, etc.
   20 
   21 Jenkins Remoting library is not in the scope for this document,
   22 because it is handled as a sub-project with independent maintainer team.
   23 Remoting updates in the core are subject to the process though.
   24 
   25 == Team
   26 
   27 === Communication channels
   28 
   29 * Mailing list: link:https://groups.google.com/d/forum/jenkinsci-dev[Jenkins Developer Mailing List]
   30 * Chat for runtime Jenkins release coordination: `#jenkins-release` on Freenode IRC
   31 ** All async communications should go to the developer mailing list
   32 
   33 === Roles
   34 
   35 * Contributor
   36 * Issue Triage Team Member 
   37 * Core Pull Request Reviewer
   38 * Core Maintainer
   39 * Release Team Member
   40 
   41 **Contributors** submit pull requests to the Jenkins core and review changes submitted by others.
   42 There is no special preconditions to do so.
   43 Anyone is welcome to contribute.
   44 
   45 **Issues Triage Team Members** review the incoming issues submitted in Jenkins Jira:
   46 bug reports, requests for enhancement, etc.
   47 Special permissions are not required to take this role or to contribute.
   48 Anyone is welcome to start contributing (see the <<issue-triage,triage guidelines below>>).
   49 
   50 **Core Pull Request Reviewers** is a team for contributors who are willing to regularly review Jenkins pull requests and to eventually become Jenkins core maintainers.
   51 They get https://help.github.com/en/github/setting-up-and-managing-organizations-and-teams/repository-permission-levels-for-an-organization[Triage permissions] so that they can manage pull requests, request reviews and prepare changelog drafts in the pull request description.
   52 Their main responsibility is to triage and review the incoming pull requests,
   53 and to guide newcomer contributors who are not familiar with the project's processes.
   54 GitHub team: link:https://github.com/orgs/jenkinsci/teams/core-pr-reviewers[@jenkinsci/core-pr-reviewers].
   55 
   56 **Core Maintainers** get `Write` permissions in the repository, and hence they are able to merge pull requests.
   57 Their responsibility is to perform pull request reviews on a regular basis and to merge ready pull requests towards the weekly releases (`master` branch).
   58 They are also responsible to monitor the weekly release status and to perform triage of critical issues.
   59 GitHub team: link:https://github.com/orgs/jenkinsci/teams/core[@jenkinsci/core].
   60 
   61 **Release Team Members** are responsible for Jenkins weekly and LTS releases.
   62 Led by the link:https://jenkins.io/project/team-leads/#release[Jenkins Release Officer], they initiate releases, prepare changelogs and backport changes into the link:https://jenkins.io/download/lts/[Stable release line].
   63 Team members get `Write` permissions in the Jenkins core repository, and they also get permissions to trigger release Pipelines.
   64 
   65 === Ladder
   66 
   67 * **Contributors**. Anyone can participate.
   68   There is no precondition except having a GitHub account, just submit pull requests or comment in existing ones!
   69 * **Core Pull Request Reviewers** can be nominated by contributors in the link:https://groups.google.com/d/forum/jenkinsci-dev[developer mailing list]. 
   70 Self-nomination is fine.
   71 Decision is made by a consensus in the mailing list or via voting at the link:https://jenkins.io/project/governance-meeting/[governance meeting].
   72 * **Core Maintainers** - same process as for Core PR reviewers.
   73   All nominees must also sign an link:https://github.com/jenkinsci/infra-cla/[Individual Contributor License Agreement] before getting the permission in GitHub repositories.
   74 * **Release Team Members** are assigned by the Jenkins Release officer
   75 
   76 == Pull request review process
   77 
   78 Jenkins core is a mission-critical part of the ecosystem.
   79 We need to ensure that submitted pull requests are not only code complete,
   80 but also that they do not introduce undesired defects, breaking changes and technical debt.
   81 At the same time, we are interested to make the review process as simple as possible for contributors and maintainers.
   82 
   83 === Review goals
   84 
   85 Pull requests review in Jenkins is not just about reviewing code and accepting them if the code is OK.
   86 Core maintainers are expected to ensure feasibility and compatibility of changes,
   87 to maintain good quality of the codebase and documentation,
   88 and to ensure there is a consensus between contributors.
   89 
   90 ==== Verifying Feasibility
   91 
   92 Reviewers are expected to look at changes critically from a "product management" point of view.
   93 It's not just about the code, but also whether the change makes sense in a global / holistic way, considering existing popular plugins and the way users experience Jenkins overall.
   94 Also, not every change needs to be merged into the core.
   95 Many features would be better introduced as plugins which have separate release cycles and allow delivering changes faster.
   96 We want to extend the Jenkins core and incorporate widely used functionality and extension points there,
   97 but we try to keep the core as minimal as possible in terms of dependencies.
   98 
   99 ==== Ensuring Compatibility
  100 
  101 The Jenkins project has a long history of backward compatibility.
  102 We accept breaking changes when it is needed (security fixes, feature deprecation and removal, etc.),
  103 but ultimately the project's goal is retain as much compatibility as possible.
  104 It includes both feature compatibility and binary/API compatibility which is important for the plugin ecosystem.
  105 Although we have some tools (like https://github.com/jenkins-infra/usage-in-plugins[usage-in-plugins]) for checking API usages across open-source plugins,
  106 there is no way to confirm external usages in 3rd-party proprietary plugins which are also a part of the ecosystem.
  107 
  108 ==== Maintaining Code quality
  109 
  110 The code doesn't have to be perfect, but we want to ensure that all new code matches basic quality standards:
  111 test coverage for newly added functionality and fixes,
  112 documentation for newly introduced APIs,
  113 the submitted code is readable and matches the code style in the surrounding codebase,
  114 etc.
  115 
  116 ==== Code style
  117 
  118 We're aware that there are existing inconsistencies in the code,
  119 and we do not enforce a single code style across the codebase at the moment.
  120 
  121 * New code should follow the (majority) style guide.
  122   In Jenkins core we use the link:https://www.oracle.com/technetwork/java/codeconvtoc-136057.html[these Code Conventions for the Java TM Programming Language] as a default code style
  123 * Updates to existing code should only fix formatting on the lines affected anyway to keep the diff minimal.
  124   It helps reviewers focus their attention on the specifics of the change and reduces the risk of a change from one pull request creating a conflict in another pull request.
  125 
  126 ==== Maintaining documentation
  127 
  128 * Jenkins documentation is hosted on https://jenkins.io/doc/.
  129   When a new user-facing change is added, we should encourage contributors to update documentation in downstream pull requests.
  130 * Same applies to Jenkins changelogs (link:https://jenkins.io/changelog[weekly], link:https://jenkins.io/changelog-stable/[stable]) and link:https://jenkins.io/doc/upgrade-guide/[upgrade guidelines]:
  131   We have a semi-automated process which is based on pull request summaries and labels.
  132   Core maintainers are expected to validate the entries as a part of the pull request review/merge process.
  133   See the checklist below in the _Merge process_ section.
  134 
  135 ==== Building consensus
  136 
  137 Not all changes are discussed before they are submitted as pull requests.
  138 Developer mailing lists, Jira issues and JEPs are used for discussions,
  139 but sometimes the changes go straight to the pull requests.
  140 And we are fine with that, especially for small patches.
  141 Pull requests often become a venue to discuss feasibility, underlying technical decisions and design.
  142 We are fine with that as well.
  143 If there is no consensus about the feasibility and implementation,
  144 code reviewers are expected to suggest proper channels for contributors to discuss their contribution.
  145 
  146 * A discussion in the link:https://groups.google.com/d/forum/jenkinsci-dev[Jenkins Developer Mailing List] is the default way to go
  147 * If no consensus can be reached on the mailing list,
  148   voting at the link:https://jenkins.io/project/governance-meeting/[Jenkins Governance Meeting] can be used to get a final decision.
  149 
  150 === Review non-goals
  151 
  152 Code reviews do NOT pursue the following goals:
  153 
  154 * Accepting/merging any pull request. 
  155   Not everything is going to be merged, and reviewers are expected to focus on the Jenkins ecosystem integrity first.
  156   We guide contributors and help them to get their changes integrated, but it needs cooperation on both sides.
  157   It is **fine** to close invalid and inactive pull requests if there is no activity by a submitter or other contributors.
  158 * Enforcing a particular coding style.
  159   Jenkins core has a complex codebase created by many contributors, and different files have different designs.
  160   Our main goal is to firstly have the code readable by other contributors.
  161 * Make contributors fix issues that are not related to the primary topic of the pull request
  162 ** Create follow-up issues instead, it is fine to reference them in comments so that the contributor might want to pick them up
  163 * Make contributors to have atomic commit history or to squash their pull request
  164 ** Not every contributor is a Git expert, do not request changes in the commit history unless it is necessary
  165 ** Core maintainers can squash PRs during the merge.
  166    If you feel this is important, add the link:https://github.com/jenkinsci/jenkins/pulls?q=is%3Aopen+is%3Apr+label%3Asquash-merge-me[squash-merge-me] label
  167 ** We want to keep pull requests focused when possible (one feature / fix per pull request),
  168    but we can live without it if there is no need to backport changes to the stable baseline.
  169 
  170 == Issue triage
  171 
  172 Jenkins core and most of its components use link:https://issues.jenkins-ci.org/[Jenkins Jira] as an issue tracker.
  173 This issue tracker is open to all Jenkins users.
  174 They report defects and requests for enhancements,
  175 and then component maintainers triage issues and provide feedback to users.
  176 In the case of the Jenkins core, *Issue Triage Team* and *Core Maintainers* are roles who are expected to process the incoming issues.
  177 These contributors perform initial triage of incoming issues and periodically scrub the issue tracker.
  178 
  179 This section provides some tips and tricks about triaging issues submitted to the Jenkins core.
  180 
  181 === Issue tracker structure
  182 
  183 Jenkins core uses the link:https://issues.jenkins-ci.org/projects/JENKINS[JENKINS] project for issue tracking.
  184 This project is shared between the Jenkins core components and plugins,
  185 and the Jenkins core is scattered across multiple components: `core`, `remoting`, `cli`, `winstone-jetty`, etc.
  186 In addition to it, there is a default `_unsorted` component which is recommended by default for users
  187 who do not know what is the root cause of an issue they experience.
  188 
  189 Searching for all Jenkins core issues is not trivial, and we provide Jira filters for it.
  190 
  191 === How to discover untriaged issues?
  192 
  193 * Community rating in Jenkins link:https://www.jenkins.io/changelog/[Regular (Weekly)]
  194   and link:https://www.jenkins.io/changelog-stable/[LTS] releases.
  195   Such ratings allow users to reference issues they experienced with new Jenkins core releases,
  196   and it helps to discover regressions in the core causing instability or unexpected plugin failures.
  197 * link:https://issues.jenkins-ci.org/secure/Dashboard.jspa?selectPageId=20742[Jenkins core triage board] -
  198   Lists untriaged and recent issues in the Jenkins core and bundled components.
  199 * link:https://issues.jenkins-ci.org/secure/Dashboard.jspa?selectPageId=20340[Core maintainers board] -
  200   Lists unresolved recent regressions, unresolved recent core bugs, and popular new issues.
  201   This dashboard can be used to discover issues that **might** be related to the recent changes in the Jenkins core.
  202 
  203 === HOWTO: Initial triage
  204 
  205 Initial issue triage has the following objectives:
  206 
  207 * **Perform initial triage of an issue**.
  208   Issue triage team members are not expected to perform a full analysis of the issue (though they are welcome to do so!).
  209   The main goal is to ensure that an issue report is legitimate and that it contains enough information to be processed.
  210   It is fine to request additional information from submitters and/or to refer them to reporting guidelines:
  211 ** link:https://www.jenkins.io/participate/report-issue/[Guide: How to report an issue in Jenkins]
  212 ** link:https://github.com/jenkinsci/remoting#reporting-issues[Reporting Jenkins Remoting issues]
  213 * **Verify the issue component**.
  214   It is essential to ensure that the `component` field references the right component (the Jenkins core, a plugin, etc.)
  215   so that an issue can be discovered and processed by a component maintainer.
  216   When moving an issue, assign the issue to the `automatic` assignee so that the maintainer gets a notification.
  217   Not all components have a default assignee, and it is perfectly fine to leave the assignee field empty.
  218 * **Verify the issue type**.
  219   `Bug` should be used for bug reports.
  220   All other issue types are considered as requests for enhancements, and there is no practical difference for the Jenkins core.
  221 * **Verify the issue metadata**: Jenkins version, environment, labels, etc.
  222   Such metadata is useful for further triage and issue discoverability.
  223   There are some labels used in Jenkins Jira dashboard and filters, e.g. `jcasc-compatibility`, `java11-compatibility`, `jep-200`, etc.
  224   Assigning such labels helps users and maintainers to discover issues and act on them.
  225   There is no list of such "common labels" recommended for use.
  226   Some labels can be found in similar issues or documentation linked from system log entries in the reports.
  227 * **Move security issue** to the `SECURITY` project.
  228   Sometimes the issue reporters do not follow the link:https://www.jenkins.io/security/#reporting-vulnerabilities[vulnerability reporting] process and report security issues in public.
  229   If you see such issues, move them to the `SECURITY` project so that the security team takes care of their triage.
  230   Note that the required fields are different between projects, so some manual updates might be required when moving them.
  231 * **Label regressions and CC stakeholders** if an issue is reported as a regression with a clear root cause,
  232   please set a `regression` label and, if applicable, CC contributors of a change which led to the regression.
  233 * **Resolve invalid issues and support requests**.
  234   Sometimes Jenkins Jira is used as a support portal.
  235   We do not want to encourage that.
  236   Jenkins Jira is an issue tracker, and we expect reporters to investigate issues on their side to an extent that they can be reviewed by maintainers.
  237   For support requests users are expected to use link:https://www.jenkins.io/mailing-lists[mailing lists],
  238   link:https://www.jenkins.io/chat/[chats] and other resources (e.g. Stackoverflow).
  239   It is fine to link users to link:https://github.com/jenkinsci/.github/blob/master/SUPPORT.md[this page]. 
  240 * **Resolve duplicates**.
  241   It is often that the same issue is already reported in the Jenkins database.
  242   Newly reported duplicates can be just resolved with a `Duplicate` resolution, and linked to the original issue.
  243 
  244 === HOWTO: Triage by maintainers
  245 
  246 Further triage focuses on confirming the issue and defining a potential resolution.
  247 It can be performed by _Issue Triage Team Members_ if they want to dive deeper,
  248 or they can leave it to component maintainers.
  249 
  250 Triage objectives:
  251 
  252 * **Confirm reported defects**. Try to reproduce the issue or analyze the codebase.
  253   If the issue is legitimate, it is great to explicitly confirm it in a comment.
  254 * Nice2Have: **Define next steps**.
  255   If possible, define a potential resolution for the issue.
  256   If you do not plan to work on the issue in foreseeable future,
  257   it is great to explicitly highlight that by unassigning the issue and inviting the reporter and other contributors to submit a fix.
  258 * Nice2Have: **Highlight newcomer-friendly issues**.
  259   Newcomer-friendly issues are instrumental for an onboarding new code contributors to the project.
  260   They are linked from link:https://www.jenkins.io/participate/code/[contributing guidelines].
  261   If you see a simple issue but do not plan to work on it,
  262   put a `newbie-friendly` label on it so that somebody could pick it up.
  263 
  264 === How to scrub issues?
  265 
  266 In addition to the initial triage, it is a good practice to sometimes review previously reported issues so that we could minimize backlog of issues and simplify search by users.
  267 
  268 * **Triage reopened issues**.
  269   Same as for newly reported issues, it is great to process reopened issues if they are not acted on by the issue assignees.
  270   Often such issues can be resolved with a request to report a new issue if an issue is reopened due to another issue.
  271 * **Resolve stale untriaged issues**.
  272   Issue reporters may become unresponsive before their issue can be fully triaged.
  273   If there is a reported issue which does not contain data for reproducing the issue,
  274   it is fine to resolve them after a 2-week timeout with the `Incomplete` or `Cannot reproduce` resolution.
  275 * **Resolve/update obsolete issues**.
  276   Sometimes issues become obsolete due to other changes in the Jenkins core (e.g. feature removal),
  277   and such issues can be closed.
  278   Same for detaching functionality from the Jenkins core and plugins,
  279   issues can be reassigned to the new Jira component so that they are removed from the core backlog.
  280 
  281 === Triaging requests for enhancement
  282 
  283 Requests for enhancement (RFEs) include the `New Feature` and `Improvement` types in Jenkins Jira.
  284 The process to triage them might be different than bug reports.
  285 because it is not always possible to say whether a request should be implemented in the Jenkins core,
  286 an existing or a new plugin.
  287 In the case of doubt, it is fine to just skip an issue or CC subject matter experts who could advice.
  288 
  289 For RFEs which are not related to the Jenkins core or plugins,
  290 it is possible to set the `plugin-proposals` component.
  291 Note that this component is not regularly scrubbed,
  292 and it can be considered only as a pool of ideas somebody could implement.
  293 It is a good practice to set expectation in a comment when updating the RFE.
  294 
  295 === Responding to pings in triaged issues
  296 
  297 Some submitters and users tend to ping triage contributors to ask about the fix ETA.
  298 In some cases, they may also assign the issue and keep pinging.
  299 It is fine to not answer these questions on such pings and to refer requestors to this document,
  300 triage team members are not responsible for handling the ticket after initial triage.
  301 
  302 Other materials which might help:
  303 
  304 * link:https://www.jenkins.io/participate/code/[Contribute to Jenkins / Code] or 
  305   link:https://github.com/jenkinsci/jenkins/blob/master/CONTRIBUTING.md[Contributing to the Jenkins Core] - 
  306   extended version of "feel free to contribute".
  307 * link:https://github.com/jenkinsci/.github/blob/master/SUPPORT.md[Jenkins Support Disclaimer Page] -
  308 for those requesters who expect quick response and SLA.
  309 * link:https://www.jenkins.io/doc/developer/plugin-governance/adopt-a-plugin/[Plugin Adoption Policy] -
  310 for pings in not actively maintained components.
  311 * link:https://www.jenkins.io/project/conduct/[Jenkins Code of Conduct] -
  312 when it gets ugly.
  313 
  314 === Resolving vs. Closing issues
  315 
  316 Jira workflow for the `JENKINS` project has two similar states: `Resolved` and `Closed`.
  317 Historically the issues are rarely being **closed**, and all dashboard and Jenkins processes interpret resolved issues as closed.
  318 The main difference is that the _Resolved_ issues can be reopened by users while _Closed_ ones can be reopened by admins only.
  319 
  320 For triage purposes, it is recommended to use the `Resolved` state if there is a chance that the issue will be reopened by the reporter or other contributor
  321 (e.g. resolving due to inactivity, disagreement with the resolution, etc.).
  322 
  323 == Merge process
  324 
  325 === Common merge process
  326 
  327 ==== Step 1: Maintainer checklist
  328 
  329 Merge process can be initiated once a pull request matches the requirements:
  330 
  331 * Pull request is compliant with requirements to submitters (see the link:/.github/PULL_REQUEST_TEMPLATE.md[pull request template])
  332 * There are at least 2 approvals for the pull request and no outstanding requests for change
  333 * Conversations in the pull request are over OR it is explicit that a reviewer does not block the change (often indicated by line comments attached to an approving PR review, or by using the term "nit", from "nit-picking")
  334 * Changelog entries in the PR title and/or _Proposed changelog entries_ are correct and reflect the current, final state of the PR
  335 * Proper changelog labels are set so that the changelog can be generated automatically.
  336  List of labels we use for changelog generation is available link:https://github.com/jenkinsci/.github/blob/master/.github/release-drafter.yml[here].
  337 * If the change needs administrators to be aware of it when upgrading, the `upgrade-guide-needed` label is present
  338   and there is a `Proposed upgrade guidelines` section in the PR title
  339   (link:https://github.com/jenkinsci/jenkins/pull/4387[example]).
  340   This is usually the case when a data migration occurs, a feature has been removed, a significant behavior change is introduced (including when there is a way to opt out),
  341   or in general when we expect at least a large minority of admins to benefit from knowing about the change, e.g. to apply a new option.
  342 * If it would make sense to backport the change to LTS, a Jira issue must exist, be a _Bug_ or _Improvement_, and be labeled as `lts-candidate` to be considered (see link:https://issues.jenkins-ci.org/issues/?filter=12146[this Jira query]).
  343 
  344 ==== Step 2: Is it a good time to merge?
  345 
  346 link:https://jenkins.io/security/[Jenkins security updates] are coordinated with the LTS calendar and if the weekly release on the weekend before an LTS release introduces regressions, users of the weekly line may have to choose between security fixes and a working Jenkins.
  347 The Jenkins security team will usually send a "pre-announcement" to link:https://groups.google.com/forum/#!forum/jenkinsci-advisories[the advisories list] on Wednesday or Thursday the week before release, but that's not always doable.
  348 For these reasons, the following changes should not be merged during the week before LTS releases (weeks 3, 7, 11, 15, etc. on the page linked above):
  349 
  350 * Changes that could be considered risky (relatively high risk of introducing regressions), as they could make users of Jenkins weekly releases choose between getting security fixes, and having a functioning Jenkins
  351 * Very large changes (in terms of lines changed), because the Jenkins security team needs to prepare security fixes for the weekly release line in a very short period of time.
  352 
  353 If the change is ready but it is not a good time, consider labeling the pull request with the `on-hold` label.
  354 Make sure to add a comment explaining why it was put on hold.
  355 
  356 ==== Step 3: Marking for merge
  357 
  358 Once the checklist is passed, a Core PR Reviewer or a Maintainer can mark the pull request for merge.
  359 
  360 * `ready-for-merge` label is set
  361 * An explicit comment is added to the pull request so that other repository watchers are notified.
  362   Example: _Thanks to all contributors! We consider this change as ready to be merged towards the next weekly release. It may be merged after 24hours if there is no negative feedback_
  363 
  364 ==== Step 4: Merge!
  365 
  366 A Core Maintainer merges the change after allowing sufficient time for comment (if needed).
  367 After that the change will be landed in the next weekly release.
  368 LTS backporting, if needed, will be handled separately by the release team.
  369 
  370 === Exceptions
  371 
  372 * Jenkins Security Team uses a different process for security issue fixes.
  373   They are reviewed and integrated by the Security team in private repositories.
  374   Security hardening and enhancements go through the standard process.
  375 * Release Team members are permitted to bypass the review/merge process if and only if a change is needed to unblock the security release.
  376   Common review process is used otherwise.
  377 * 24 hours waiting period after adding the `ready-for-merge` label is not required for:
  378 //TODO(oleg_nenashev): Define "trivial" better to avoid loopholes
  379 ** changes that do not result in changes to the primary functionality, such as typo fixes in documentation or localization files
  380 ** changes which do not affect the production code: Jenkinsfile tweaks, tools inside the repo, etc. 
  381 ** broken master build
  382 
  383 === Squashing pull requests OR not?
  384 
  385 Sometimes we have pull requests which include dozens of commits including many non-substantial changes (merge commits, addressing review comments, etc.).
  386 We do not require contributors to spend time on cleaning it up, because core maintainers can squash PRs during the merge.
  387 Reviewers can add a link:https://github.com/jenkinsci/jenkins/pulls?q=is%3Aopen+is%3Apr+label%3Asquash-merge-me[squash-merge-me] label during reviews to highlight that it is needed.
  388 
  389 At the same time, we do not require any pull request to be merged as a single commit.
  390 Multiple commits are useful in many cases.
  391 
  392 When do we merge pull requests as is?
  393 
  394 * There is only one commit with a reasonable commit message
  395 * There are multiple atomic commits. Each commit has a reasonable message and can be compiled on its own
  396 ** Example:
  397 *** **Commit 1**: `[JENKINS-1234] - Reproduce the issue in tests`
  398 *** **Commit 2**: `[JENKINS-1234] - Fix the issue by updating Foo` 
  399 * There are multiple commit authors who expressed the desire to keep commit history as is.
  400   By default we do not consider multiple authors as a blocker for squash, because GitHub now 
  401   link:https://help.github.com/en/github/committing-changes-to-your-project/creating-a-commit-with-multiple-authors[supports co-authors]
  402 
  403 When do we squash commits?
  404 
  405 * We squash commits when core maintainers decide to do so (`squash-merge-me` label), usually when the conditions above are not met.
  406 * There is no strong requirement to squash merge pull requests at the moment, so there might be deviations from the merge policy in practice.
  407 
  408 == Weekly release process
  409 
  410 link:https://www.jenkins.io/download/weekly/[Jenkins Weekly releases] are managed by the Jenkins Release Team which has access to the dedicated release environment within the Jenkins Infrastructure.
  411 References:
  412 
  413 * link:https://www.jenkins.io/download/weekly/[Jenkins Weekly Releases Documentation]
  414 * link:https://github.com/jenkins-infra/release[Jenkins Release Environment and the release process]
  415 * link:https://github.com/jenkinsci/packaging[Native Jenkins packages and installers for platforms]
  416 * link:https://github.com/jenkinsci/docker[Docker packaging for Jenkins]
  417 
  418 == LTS Process
  419 
  420 Jenkins also offers the link:https://jenkins.io/download/lts/[LTS Release Line].
  421 It is maintained by the Jenkins Release Team which coordinates link:https://jenkins.io/download/lts/#backporting-process[backporting] and release candidate testing.
  422 Any Jenkins contributors are welcome to participate in backporting and release candidate testing.
  423 
  424 * Backporting discussions happen through the developer mailing list.
  425 * Backports are submitted as pull requests with the link:https://github.com/jenkinsci/jenkins/labels/into-lts[into-lts] label.
  426 * Release candidate testing is announced in the developer mailing list.
  427   Discovered issues should be submitted to Jenkins Jira and then referenced in the release candidate testing thread.
  428 
  429 == Tools
  430 
  431 * link:https://issues.jenkins-ci.org/secure/Dashboard.jspa?selectPageId=20340[Core maintainers board] -
  432   Lists unresolved recent regressions, unresolved recent core bugs, and popular new issues.
  433 * link:https://github.com/jenkinsci/core-pr-tester[Core Pull Request Tester]
  434 * link:https://github.com/jenkinsci/core-changelog-generator[Core Changelog Generator]
  435 * link:https://github.com/jenkins-infra/backend-commit-history-parser[Toolkit for LTS backporting]
  436 * link:/update-since-todo.sh[Javadoc @since version updater]
  437 
  438 == Feedback
  439 
  440 The process documented in this document is not set in stone.
  441 If you see any issues or want to suggest improvements,
  442 just submit a pull request or contact us in the communication channels referenced above.
  443 Any feedback will be appreciated!