The Fix
pip install celery==5.0.3
Based on closed celery/celery issue #6047 · PR/commit linked
Production note: Most teams hit this during upgrades or environment changes. Roll out with a canary and smoke critical endpoints (health, OpenAPI/docs) before 100%.
@@ -210,7 +210,7 @@ To use this with your project you need to follow these steps:
.. code-block:: python
- CELERY_CACHE_BACKEND = 'django-cache'
+ CELERY_RESULT_BACKEND = 'django-cache'
Option A — Upgrade to fixed release\npip install celery==5.0.3\nWhen NOT to use: This fix should not be applied if the documentation is already accurate.\n\n
Why This Fix Works in Production
- Trigger: Users were unable to configure Django cache for task results, leading to confusion.
- Mechanism: Documentation incorrectly stated that CELERY_CACHE_BACKEND is no longer used
- Why the fix works: Fixes issue #6047 by correcting a typo in the documentation and adding documentation for the cache_backend setting for the Django Celery backend. (first fixed release: 5.0.3).
- If left unfixed, the same config can fail only in production (env differences), causing startup failures or partial feature outages.
Why This Breaks in Prod
- Documentation incorrectly stated that CELERY_CACHE_BACKEND is no longer used
- Production symptom (often without a traceback): Users were unable to configure Django cache for task results, leading to confusion.
Proof / Evidence
- GitHub issue: #6047
- Fix PR: https://github.com/celery/celery/pull/6535
- First fixed release: 5.0.3
- Reproduced locally: No (not executed)
- Last verified: 2026-02-09
- Confidence: 0.75
- Did this fix it?: Yes (upstream fix exists)
- Own content ratio: 0.78
Discussion
High-signal excerpts from the issue thread (symptoms, repros, edge-cases).
“Thanks for the report @rob101. Have you verified this behavior with latest versions? If yes, then would you like perhaps to open a Pull Request…”
“would love to know the current status and glad to see a PR!”
Failure Signature (Search String)
- Users were unable to configure Django cache for task results, leading to confusion.
Copy-friendly signature
Failure Signature
-----------------
Users were unable to configure Django cache for task results, leading to confusion.
Error Message
Signature-only (no traceback captured)
Error Message
-------------
Users were unable to configure Django cache for task results, leading to confusion.
What Broke
Users were unable to configure Django cache for task results, leading to confusion.
Why It Broke
Documentation incorrectly stated that CELERY_CACHE_BACKEND is no longer used
Fix Options (Details)
Option A — Upgrade to fixed release Safe default (recommended)
pip install celery==5.0.3
Use when you can deploy the upstream fix. It is usually lower-risk than long-lived workarounds.
Fix reference: https://github.com/celery/celery/pull/6535
First fixed release: 5.0.3
Last verified: 2026-02-09. Validate in your environment.
When NOT to Use This Fix
- This fix should not be applied if the documentation is already accurate.
Did This Fix Work in Your Case?
Quick signal helps us prioritize which fixes to verify and improve.
Prevention
- Capture the exact failing error string in logs and tests so you can reproduce via a minimal script.
- Pin production dependencies and upgrade only with a reproducible test that hits the failing path.
Version Compatibility Table
| Version | Status |
|---|---|
| 5.0.3 | Fixed |
Related Issues
No related fixes found.
Sources
We don’t republish the full GitHub discussion text. Use the links above for context.