Use uvicorn --factory for fast_web — save ~100MB of RAM - #13404
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fast_web with --reload was importing the whole app in both parent and worker (172MB + 171MB). Switch to factory uvicorn --factory openlibrary.asgi_app:create_app per https://fastapi.tiangolo.com/deployment/ and https://uvicorn.dev/#application-factories Remove app = create_app() from openlibrary/asgi_app.py, update docker/ol-web-fastapi-start.sh (prod now openlibrary.asgi_app:create_app()). Saves ~100MB overall, no compose changes.
cdrini
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Aug 25, 2026
Co-authored-by: Drini Cami <cdrini@gmail.com>
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Lgtm! Confirmed working smoothly on testing. Woohoo less RAM! 🥳
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fast_web with --reload was importing the app in both parent and worker (172MB + 171MB).
Switch to factory
uvicorn --factory openlibrary.asgi_app:create_appper https://fastapi.tiangolo.com/deployment/ and https://uvicorn.dev/#application-factories. Removeapp = create_app()fromopenlibrary/asgi_app.py, updatedocker/ol-web-fastapi-start.sh(prod nowopenlibrary.asgi_app:create_app()).Saves ~100MB overall, no compose changes.