VPS Setup

Purpose

The actual server setup steps — directly from the earlier conversation, formalized as a reference doc.

Spec (starting point, from the original conversation)

• Ubuntu Server 24.04
• 4 cores / 8 GB RAM / 160 GB SSD (adjust up once real traffic data exists — this was an illustrative starting spec, not a locked requirement)

Setup Sequence

Buy VPS
  ↓
Install Ubuntu
  ↓
SSH in (key-based only — see Security below)
  ↓
Install Node
  ↓
Install Nginx
  ↓
Install SSL (Let's Encrypt)
  ↓
Deploy app
  ↓
Configure firewall
  ↓
Configure backups
  ↓
Configure monitoring

Note: PostgreSQL is NOT installed on the VPS itself (see Hosting Strategy — managed Postgres instead), which simplifies this sequence compared to the original fully-self-hosted version discussed earlier.

Security Baseline (from the original conversation)

• Firewall: only ports 80, 443, 22 open
• SSH: key-based only, no password login
• HTTPS: Let's Encrypt via Nginx
• No direct public exposure of any database (not applicable here anyway, since Postgres is managed and off-VPS)

Open Questions

• None blocking — this is a direct carryover of the already-agreed-upon setup from the earlier conversation.

Update (2026-08-03): Two runtimes now needed

Following the FastAPI backend decision, the VPS needs both Node (for the Next.js frontend) and Python (for the FastAPI backend) installed, not just Node. Updated setup sequence:

flowchart TD
    A[Buy VPS] --> B[Install Ubuntu]
    B --> C[SSH in, key-based only]
    C --> D[Install Node - for frontend]
    D --> E[Install Python + pip/uv - for backend]
    E --> F[Install Nginx]
    F --> G[Install SSL - Let's Encrypt]
    G --> H[Deploy frontend - Next.js]
    H --> I[Deploy backend - FastAPI, via uvicorn/gunicorn]
    I --> J[Configure firewall]
    J --> K[Configure backups]
    K --> L[Configure monitoring]

Nginx now routes to two upstream processes (frontend on one port, FastAPI backend on another) instead of one — see System Architecture's updated diagram.

Update (2026-08-04): Multi-Worker Deploy (Load Balancing Active)

FastAPI backend now deploys as gunicorn managing multiple uvicorn workers (not a single process), with Nginx load-balancing across them — see 06. Scaling Strategy for the full reasoning. Worker count sized to VPS CPU cores once provisioned. No change to the Node/Python dual-runtime setup above, just how the backend process itself runs.

Update (2026-08-23): Frontend Moved to Vercel — VPS Is Backend-Only

Per Hosting Strategy's 2026-08-07 decision, the frontend (Next.js) now deploys on Vercel, not this VPS. The "Install Node - for frontend" and "Deploy frontend - Next.js" steps in the 2026-08-03 setup sequence above are no longer needed on the VPS. Nginx no longer routes to two upstream processes — it fronts the single FastAPI backend process only (see Reverse Proxy (Nginx) for the updated topology). From this point, VPS setup is backend/Python + Nginx only:

flowchart TD
    A[Buy VPS] --> B[Install Ubuntu]
    B --> C[SSH in, key-based only]
    C --> D[Install Python + pip/uv - for backend]
    D --> E[Install Nginx]
    E --> F[Install SSL - Let's Encrypt]
    F --> G[Deploy backend - FastAPI, via uvicorn/gunicorn]
    G --> H[Configure firewall]
    H --> I[Configure backups]
    I --> J[Configure monitoring]