Attending: Sanket Verma (SV), Josh Moore (JM), Davis Bennett (DB), Ryan Abernathey (RA), Dennis Heimbigner (DH), Hailey Johnson HJ), Ward Fisher (WF), Jonathan Striebel (JS)


SV is going to speak at PyData Global 2022 next week and also going to run a sprint along with JM. Details for the talk are here and sprint here. During the meeting a proposal to host a Discord server for chunked formats was raised by DB which later converted to creating a Discord server for the Zarr community. JM gave updates revolving around zarr-java, and lastly SV initiated the discussion on how we can separate Zarr (file storage format) from zarr-python (Python implementation of the Zarr spec).


  • ZEP1 Update, see here
    • Check out the ZEP1 GH Project board here; maintained by Jonathan Striebel
  • PyData Global 2022 Sprint next-to-next week(1st-3rd Dec.), anyone interested in helping out?
    • Need to know by this week
    • Also: Sanket giving a talk, “The Beauty of Zarr”

Meeting Minutes:

  • DB: Discord for Chunked Formats?
    • Had problem and TypeScript Community was very helpful.
    • New thread gets created per issue
    • Downside: not indexed by google
    • WF: like it, use it socially, want this to be a solution
    • WF: have people pushing people to github
    • RA: pangeo uses discourse. bringing more dialogue together?
      • critical is the granularity so we get take home
    • DB: activation for forum post is 10x to discord message
    • WF: discord seems more synchronous
      • wouldn’t work for NC since there wouldn’t be enough critical mass
      • gitter straddles the line, since there’s a lot to catch up on
      • but one for sync and async would be good
    • RA: don’t see the other chunked formats being psyched to be in a channel with us. workflow might be the more useful framing
  • zarr-java: discussions tomorrow about bringing back two forks of jzarr
    • JM (re-surfacing) care with Python discord? Yes.
      • HJ: always start by clarifying library vs file format
    • WF: good feedback on Zarr at unidata user committee meeting
      • being asked for in THREDSS
    • DH: recent discussion around ragged arrays
      • most people encounter zarr through python
      • that leads to an imprinting
      • when they run into nczarr, they are perplexed (things missing)
      • still a big problem
    • JS: incompatibilities between libraries could bring us down
      • v3 is spec first with feedback from different implementors
      • hopefully to drop python-specifics and possible to know what the incompatibilities are
      • claim: “Zarr is X”, not just “a community project”
        • posters, repos, webpages, etc…
        • currently hard to grasp
    • SV: how to separate from Python
      • DH: go through tutorial and move things that are not in the v2 spec
      • DH: probably many go through the tutorial
      • DH: e.g. fortran community
      • JM: good points, but the same will be true for nczarr. v3 will give us the chance to label things more clearly.
      • WF: have to be clear about “NetCDF”. Was specific talking to the user committee about the “Zarr data model”, or “Zarr data storage”
        • specificity in language. data model and the format should be cross-language.
      • DH: ultimately goal is the nczarr extensions to be v3 extensions
      • JM: wonderful :tada: when would be a good time to plan for that?
      • DH: currently working on DAP4, but will shoehorn some time for bullet point list of extensions (and why)