Storybook Release Proposal

A Storybook release process based on Semver. In short:

merge bugfix PRs directly into master automatically release (~daily)
merge feature and breaking PRs into a release branch (e.g. release/3.2) and release features in groups along with a marketing push after a preview period (~monthly)

Motivation

During the Storybook 3.x transition we've undergone a series of growing pains as we've opened up the development process. We've had questions about:

how to adhere to semver?
how to do marketing releases (while adhering to semver)?
how to introduce significant new features (e.g. vue support, story hierarchy)?
how to converge on key design decisions (e.g. new addons API)?
how to schedule releases?
how to maintain quality/stability through the process?

This proposal attempts to address all of these concerns in one shot.

Semver

Semver dictates three types of release:

MAJOR version when you make incompatible API changes,
MINOR version when you add functionality in a backwards-compatible manner, and
PATCH version when you make backwards-compatible bug fixes.

We'll do our best to adhere to Semver, but won't be religious about it. In particular, we may occasionally release small bits of new functionality in PATCH releases. We'll try our best to restrict breaking changes to MAJOR releases.

PATCH releases

Every bugfix should go out as soon as we've verified the fix, and based on the current rate of contribution, we should be issuing PATCH releases multiple times per week. Soon we'll automate the process so that a release will go out every time a PR is merged into master, and we've already laid most of the groundwork for this.

MINOR releases

Every new feature, particularly significant ones (e.g. Vue support, deep hierarchy for stories) deserves more attention:

They should be well-tested by the community before we release.
They often have architectural implications for the entire Storybook ecosystem, so should be discussed thoroughly before release. Doing alpha releases allow us to test in the community without necessarily achieving agreement. For example, currently Vue support is in alpha, although it contains potentially controversial changes to addons.
They often deserve proper marketing treatment (blog posts, release announcement, podcast, etc.)

Therefore we merge these into a release branch of the form release/MAJOR.MINOR and we create preview releases and get them tested by the community before merging those branches into master.

NOTE: it is possible to edit the base branch in a PR, so we can expect users to issue PRs to master, but as maintainers as we see feature releases we should set them to merge into the appropriate release branch.

In general we should release 2-3 headline features per minor release for marketing purposes. Each headline feature should get its own blog post on the Storybook medium publication, and the release itself should also get a blog post.

MAJOR releases

We should avoid major releases, and should try to do these at most 1-2x per year. Ideally each breaking change would have been agreed upon by the maintainers and validated in backwards-compatible feature releases. At some point once a change has been thoroughly vetted, we deprecate the old way and give some time for people to upgrade to the new way. Finally MAJOR releases should have killer features that reward users for upgrading, and should not be used to scratch our own architectural itches -- unless those itches are really killing development in some meaningful way.

Discussion

For PATCH changes, all discussion can occur in issue/PR comments (and random slack chat as needed).
For MINOR feature changes, there are multiple stages of discussion:
- The feature may be discussed in an issue before it is implemented (ex: storybookjs/storybook#151)
- Once it's implemented, the discussion may be occur on the PR (ex: storybookjs/storybook#151)
- If people disagree on an implementation and it can't be resolved in discussion, they may issue alternative PR's with different ideas
- Ultimately the maintainers will reach a concensus before merging the changes. There is no set process for this, but we're all adults.
- Since MINOR features are released in alpha before they are fully released, new issues may be created by end users, etc.
For MAJOR infrastructural changes, the discussion may take place over time, in gists like this one, issues, slack discussions, etc.
- Once the breaking changes have been reduced to an actual implementation, it looks pretty much like a feature release (only with higher stakes and probably a longer stabilization process).

FAQ's

How does my PR get merged?

For PATCH PR's, any maintainer can review, test, approve, and merge it.
For MINOR/MAJOR PR's, once a maintainer reviews, tests, and approves it, s/he should clear it with the other maintainers before merging it into the release branch.

@alexndrebodin I agree about creating new branches for every minor release. I've created a release/3.2 branch and set Vue and substory work to merge into that. Technically, according to this proposal, the Vue work should have already been merged into that branch before we release an alpha, but the whole process is still under development so it's fine.

@alexandrebodin I think the base branch should always be master. Most of the PR's we get are PATCH fixes, and I think we should get those out as they come in:

new contributors get to see their work released quickly / people get unblocked
users won't get frustrated if the MINOR releases take longer
helps us pay down tech debt continuously

@usulpro Yeah I think we can certainly have long-running feature branches and merge them into the current release branch when we are finished. In some cases, we might want to merge them into the next release branch, or next MAJOR release branch instead.

shilman/RELEASE.md