This SPEC recommends that projects test against nightly wheels of several widely-used projects in the Scientific Python ecosystem.

There are two main motivations for this recommendation:

  1. Testing against nightly wheels will help identify when changes to the main branch of the widely-used projects break downstream projects.
  2. By using the nightly wheels projects will not have to build packages from source, which can be difficult and time consumming.


We recommend that projects add a cron job to test against the nightly wheels and when errors are encountered to automatically open an issue in their project so they can investigate.

The nightly wheels for conda can be found here.

We have a GitHub action to upload new nightly wheels and remove old ones:

Core Project Endorsement

Ecosystem Adoption