I am using bitwarden_RS in a serverless environment (Cloud RUN - uses Knative) with postgres backend (managed).
It’s working fine, you just need to disable the attachment functionality.
Here my env settings to auto-configure my containers:
USER_ATTACHMENT_LIMIT 0
ORG_ATTACHMENT_LIMIT 0
DATABASE_URL postgresql://user:password@IP:port/dbName
SMTP_HOST xxxxxxxxx
SMTP_PORT xxxxxxxxx
SMTP_SSL true
SMTP_USERNAME xxxxxxxxx
SMTP_PASSWORD xxxxxxxxx
SMTP_FROM xxxxxxxxx
DOMAIN https://xxxxxxxxx.xx
ADMIN_TOKEN admintoken
SMTP_FROM_NAME xxxxxxxxx
SIGNUPS_ALLOWED false