Request for Review of ZEP0001

[jstriebel]

Dear Zarr council members, ^{(@zarr-developers/steering-council @zarr-developers/implementation-council)}

It's time to apply the Zarr enhancement proposal process for the
first time! We kindly ask you to review the proposal

ZEP 1 - Zarr specification version 3 with its specs

• Zarr core specification (version 3.0)
• Codecs

Please note that some changes are still in progress, especially regarding the file
hierarchy, see issues

• #178: Issue overview: From URI to open array
• #177: Consider to drop /meta prefix

An overview of all open issues and PRs around ZEP 1 can be found
in this project board.

We will feature-freeze the specification from 19. December, only
incorporating changes that have previously been discussed after the freeze. Then, we
would like you to vote if ZEP 1 should be marked as "Provisionally
Accepted"¹, by the end of January. "Provisionally Accepted" would signal that the
specifications are ready to be implemented, but gives us the freedom to improve
them if any further problems arise during the first implementations. We hope
that this timeline is in everybody's interest and helps us to move forward with
Zarr v3. More information about this vote and the implications will follow separately.

We recognize that reviewing ZEP 1 is a lot of effort and many of you have been
following the progress for some time already. In addition we are just about to
test the ZEP process for the first time. If you have any questions about the
ZEPs, the specs or the process, please feel free to reach out to us, we are also
happy to jump onto a call.

If you mostly want to get a brief overview of the key differences between Zarr v2
and v3, the section "Comparison with Zarr v2" might help (some more changes might
still be added in the next few weeks):
https://zarr-specs.readthedocs.io/en/latest/core/v3.0.html#comparison-with-zarr-v2

Thank you all so much for your awesome work on Zarr! We highly value your input and
opinions, and hope that gathering those leads us to the next version of Zarr 🚀

All the best,
@jstriebel, @jbms & @joshmoore

---

¹ from ZEP 0 — Purpose and process:

To allow the gathering of additional design and interface feedback before
committing to long term stability for specification change or standard library
API, ZEP may also be marked as “Provisional”. This is short for “Provisionally
Accepted” and indicates that the proposal has been accepted for inclusion in
the reference implementation or storage specification, but additional user
feedback is needed before the full design can be considered “Final”. Unlike
regular accepted ZEPs, provisionally accepted ZEPs may still be Rejected or
Withdrawn even after the related changes have been included in a Zarr release.

[jstriebel]

Then, we would like you to vote if ZEP 1 should be marked as "Provisionally Accepted", by the end of January.

Since some more work regarding the spec is still in progress, we plan to start the voting phase end of February instead, giving one month time for the votes until end of March. Please contact @joshmoore, @jbms, @MSanKeys963 or me if you have any questions regarding this.