plan for the upcoming v7.0 release

[Matthew Flatt]

The next release of Racket will be version 7.0:

* Version 7.0 is a milestone on our path to replace the old,
C-implemented runtime system with Chez Scheme.

* As such, version 7.0 reflects MAJOR INTERNAL CHANGES that make
Racket-on-Chez possible --- especially the switch to a new
implementation of the macro expander.

* Version 7.0 does *not* mean that we're switching to Racket-on-Chez as
the main Racket implementation. We're not there yet.

We do not expect Racket users to see a big difference between Racket
v6.12 and Racket v7.0. But, since the internals differ significantly, a
major-version bump tracks that change.

The internal changes make bugs and unintended incompatibilities more
likely than for a typical Racket release. To mitigate that risk, we
skipped a release cycle to give the v7 changes time to settle. We also
plan an extra "beta" testing cycle to give users a few weeks to try out
a candidate v7 release.

The v7-beta process will be similar to a normal release process, except
that we'll stop before the step of pushing v7 to the download sites.
Instead, https://pre-release.racket-lang.org/ will freeze with a "beta"
version for a few weeks. After getting feedback on that beta version,
we'll restart testing (because we anticipate changes and repairs from
the beta phase) and finish up the v7 release normally.

Here's the schedule:

* June 7: branch date for Racket v7-beta

We create a branch of the main Racket repository, and thereafter
apply only bug fixes or changes approved by release management.

* June 20-something: v7-beta "release" date

We freeze the build at https://pre-release.racket-lang.org/,
publicly announce that beta testing has started, and request your
feedback.

* July 15: start v7 testing with v7-beta branch -> v7 branch

We restart our release-time tests to check repairs for problems
that were detected during beta testing.

* Late July: v7 release


Thanks in advance for your help making the v7 transition a success!

- Racket release management