← All workClinic infrastructure · security
Clinic Data Vault
A separate, encrypted site that keeps a versioned copy of everything in the clinic system — and brought it all back when the main database went down.
AES-256encryption at rest
everyversion kept in history
2-stepowner login
1full restore done in production
Clinic data is sensitive and the main app runs on free-tier databases. I wanted a copy that lives on its own, can't be read by the main app, and keeps every past version.
Inside Clinic Data Vault
How it works
- Database triggers in each branch write changes to an outbox table.
- After every request (and on a schedule) the main app pushes the outbox to the vault with an HMAC-signed, write-only key.
- The vault encrypts each record with AES-256 and keeps a history table with every version.
- Only the owner can open it: password plus authenticator code.
It paid off
- In late October the shared database hit its compute quota and the whole clinic app went down.
- I restored every table from the vault into a new database per branch, checked counts table by table, and the app was back the same day.
- Then I split the system into one database per branch so one branch can't take down the others.
Stack
Node.js on Vercel FunctionsPostgres (Neon)HMAC-signed syncAES-256-GCMTOTP 2-step loginDB triggers + outbox