Super minimal secured secret storage
The main case is one-time sharing secret with your friend. After first read message will be destroyed (be careful with messengers preview) also you can set time-to-live of message for some secure reasons.
First of all change secrets in backend/settings.py. Configure PostgreSQL with etc/schema.sql.
Setup uvicorn and run server.
Add crontab rules from etc/crontab for auto-cleanup expired secrets.
You can change DB backend on any, just rewrite functions in backend/db.py file.