# Lmiguelvargasf Nova Backend Async Tasks > Backend async tasks (Celery) - Skill: `tomevault-io/lmiguelvargasf-nova-backend-async-tasks` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/lmiguelvargasf-nova-backend-async-tasks` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/lmiguelvargasf-nova-backend-async-tasks/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/lmiguelvargasf-nova-backend-async-tasks --- # Backend async tasks (Celery) ## When to use - You are adding or changing a Celery task in `backend/src/backend/apps/**/tasks.py`. - You need to update the Celery Beat schedule in `backend/src/backend/celery_app.py`. - You are adding DB access inside a Celery worker process. ## Steps 1. Define tasks only in a `tasks.py` file under the relevant app module. 2. Decorate tasks with `@app.task` imported from `backend.celery_app`. 3. Return a typed result (`int`, `None`, etc.). Keep task-specific parameters local unless they must be environment-configured. 4. For DB access: - Use `asyncio.run()` to bridge async work. - Always acquire a session via `get_task_session()` from `backend.celery_app`. 5. For periodic jobs, update `app.conf.beat_schedule` in `backend/src/backend/celery_app.py` and use `celery.schedules.crontab`. ## Constraints and guardrails - Never use the global `alchemy_config` engine inside a task; it is not fork-safe for Celery workers. - Always use `get_task_session()` to manage DB connections safely across worker processes. ## References - `backend/src/backend/apps/**/tasks.py` - `backend/src/backend/celery_app.py` - `backend/tests/apps/users/test_tasks.py` --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/lmiguelvargasf) — claim your Tome and manage your conversions.