PEP 784: Adding Zstandard to the standard library

PEPs
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I can see lots of support for adding Zstandard to the standard library, but no consensus for the compression package.

There’s just under a month until Python 3.14’s feature freeze.

Here’s two options.

One:

  • Keep this PEP more-or-less as is: add Zstd, and compression package. I don’t expect this to be decided in time for 3.14, but there is plenty of time before 3.15’s feature freeze in May 2026.

Two:

  • Focus this PEP only on adding Zstandard to the stdlib. There’s not a lot of time, but there is still a chance to revise the PEP, submit to the SC for consideration, have a PR reviewed and merged before the freeze.

  • And defer the compression package to another PEP targeting 3.15. Zstandard can join the 10-year deprecation along with the other compression modules. Plenty of time until May 2026 to try to find consensus.

Some figures in this 2020 thread show Zstandard would be a great choice for packaging: it’s much faster and produces smaller files.

But to be useful in packaging, it needs widespread adoption. And an extra year headstart is important. Therefore I recommend focussing this PEP only on adding zstd to the stdlib and aim for 3.14.

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