PEP 759 - External Wheel Hosting

Resource	Link
PEP Link	https://peps.python.org/pep-0759/
DPO Discussion	PEP 759, External Wheel Hosting
Github Repository

Summary

The intent of this PEP was to provide a safe mechanism for hosting wheels on external indexes (i.e. other than PyPI). It proposed a new file format called a .rim file which, like .whl files, are zip files. However, unlike .whl files, these zip files only contain the .dist-info metadata directory, and do not contain any package contents.

The PEP proposed a new file inside this metadata directory called EXTERNAL-HOSTING.json which contained some additional keys which are used to locate and verify the wheels on the external index. The primary effect of this file was to change the download URL for the actual wheel on the original index's Simple Index. Hashes are included to act as a checksum so that the external artifact could be verified to avoid bait-and-switching on the external index.

See the PEP for additional details.

Resolution

As of 31-Jan-2025, the PEP was withdrawn. The primary reason was that in the author's opinion, there was little appetite from the Python packaging community to support .rim files. Instead, the consensus appeared to be to make it easier and safer to use multiple indexes, including the adoption by index software authors for PEP 708.

Even so, PEP 759 had its fans. With a withdrawn status, PEP 759 is not officially rejected, and may be reopened in the future, if its advocates can build sufficient support.