Motivation

PYTHON-5882 exposed a gap in Django MongoDB Backend's CI coverage: a new MongoDB server-side validation for Queryable Encryption (Location9188700) was only caught on Python 3.14/3.14t in PyMongo because the test-non-standard-latest-* tasks run against MongoDB nightly builds, and those tasks are only scheduled for a subset of Python versions in the non-standard matrix.

As a result, the breakage went undetected for all other Python versions until it was manually investigated. If nightly server builds were included in the standard CI matrix, such regressions would surface immediately across all configurations.

Goal

Update CI to run a subset of tasks against the latest MongoDB nightly server build so that new server-side validations and behavior changes are caught promptly, regardless of which Python version triggered the discovery.

Proposed Changes

• Add a nightly MongoDB server build variant to the Evergreen (or equivalent) CI configuration for this project.
• Ensure the nightly variant runs at minimum the encryption/QE-related test suites.
• Ideally run nightly builds on a schedule (e.g. nightly cron) rather than only on every patch, to avoid slowing down developer workflows.

References

• PYTHON-5882: Root cause was a new server-side QE contention validation that was only exercised by nightly-server tasks limited to Python 3.14/3.14t.