shrub/MAINTAINERS.md

Maintaining

Overview

We use a three-stage release pipeline. Each stage of the release pipeline has its own dedicated branch and corresponding testing moon. Features and bug fixes progress through each stage--and are subject to testing along the way--until they're eventually released to the live network. This pipeline automates our release process, making it much easier to quickly and reliably ship code. It's also simple to reason about.

Branches and Moons

The branches and their corresponding moons that comprise the stages of the release pipeline are:

----------------------------------------------------------------------------------------------
 Branch     |            Moon          |   Target audience   |            Contains
----------------------------------------------------------------------------------------------
`develop`   | `~binnec-dozzod-marzod`  | Kernel developers   | Latest `develop` branch commit
`release`   | `~marnec-dozzod-marzod`  | Early Adopters      | Latest `release` branch commit
`release`   | `~doznec-dozzod-marzod`  | App Developers      | Latest release candidate
`master`    | `~zod`                   | Everyone else       | Latest release

WARNING: If you lack the requisite skills to troubleshoot and fix kernel issues, you should not sync from develop/~binnec. If you're not prepared to breach your ship in response to an issue stemming from an early release, do not use pre-release moons.

develop is the default branch in the repo, which means that all new pull requests target it by default. The general flow of a new feature or bug fix through the pipeline is:

feature branch ---->   develop ---->  release ---------> master
                          |              |                 |
                    deployed to    deployed to         deployed to
                    ~binnec moon ~marnec/~doznec moon  network

If an issue arises in the course of testing the release branch (because more people are using marnec than binnec), a PR can be opened to target release. If that's the case, the master needs to be merged back into develop after release merges into master to ensure that develop gets the fix.

Release Workflow

Developers work on feature branches built against develop. While doing this, they continually merge in changes from develop to their feature branch. When their feature is ready (and they've tested it), they open a pull request. After code review approval and passing tests, their feature can merge into develop. Every merge into develop immediately triggers a deploy to the binnec moon. If your merge breaks binnec it's your responsibility to fix it.

Once a week on Tuesday, a release branch is cut off of develop. This release gets deployed to marnec to be tested for the rest of the week. Any fixes that have to go into the release can go straight into the release branch. New work that didn't make the release continues on feature branches against develop (eventually merging there). After initial testing on marnec, a release candidate is tagged and merges into ~doznec where early adopters and app developers can pick it up and test or update their apps for a new kelvin. If it's a new kelvin, we also send an email to urbit-dev with instructions for testing the breaking changes.

Then on the next Tuesday the release branch merges into master and tagged using the tag instructions below, we create a GitHub release (marked latest) using that tag on master which documents the changes that went into the release. In the Github UI you can get the changelog by selecting the tag prior to it from the previous release when creating the new release. Then the release is deployed to the broader network via zod. Master is then merged back into develop where any fixes that went straight to release get picked up. Lastly, a new release branch is cut from develop and the process begins again.

Tagging

When we branch release to deploy to ~marnec, we need to tag it as a release candidate (RC), like urbit-os-vx.y-rc1. Here 'x' is the major version and 'y' is an OTA patch counter. After this any change that goes into release gets a new tag that increments the rc.

After we ship a release to the live network, add a tag that is not a release candidate, like urbit-os-vx.y, to the master branch, since that's what was released.

Applying the Tag Locally

Use an annotated tag with the -a git argument. Make sure to follow the naming convention for RCs and live releases, described above.

To add a tag to the local repo, run this:

git tag -a <tagname>

This will bring up an editor, where you should add the release notes, which should look like this:

<tagname>

This release will be pushed to the network as an over-the-air update.

Release notes:

  [..]

Contributions:

  [..]

To fill in the "contributions" section, copy in the shortlog between the last release and this release, obtained by running this command:

git shortlog --no-merges LAST_RELEASE..

Pushing the Tag to the Main Repo

Once you have added a tag, push it to the main repository using the following command:

git push origin <tagname>