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Fetch the complete documentation index at: https://mintlify.com/pvnm4/Social-Media-Backend/llms.txt

Use this file to discover all available pages before exploring further.

The repository ships with a render.yaml Blueprint file that lets you provision both the FastAPI web service and a managed PostgreSQL database on Render.com in a single click. No manual service configuration is required — Render reads the Blueprint and creates every resource with the correct settings, environment variables, and inter-service wiring automatically.

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What render.yaml configures

The render.yaml file at the root of the project defines the full infrastructure for the application: 
databases:
  - name: fastapi-db
    databaseName: fastapi_tutorial
    user: fastapi_user
    plan: free # Free tier: 1 GB storage, expires after 90 days
    ipAllowList: [] # Allow connections from any IP

services:
  - type: web
    name: fastapi-tutorial
    runtime: python
    plan: free # Free tier: 512 MB RAM, spins down after 15 min inactivity
    buildCommand: "pip install uv && uv sync"
    startCommand: "uv run uvicorn app.main:app --host 0.0.0.0 --port $PORT"
    envVars:
      - key: PYTHON_VERSION
        value: 3.14
      - key: DATABASE_URL
        fromDatabase:
          name: fastapi-db
          property: connectionString
Here is what each section does: databases block Provisions a free-tier PostgreSQL instance on Render with:
  • Instance name: fastapi-db (used internally to reference the database from services)
  • Database name: fastapi_tutorial
  • Database user: fastapi_user
  • Plan: free — 1 GB storage, expires after 90 days
  • ipAllowList: [] — allows inbound connections from any IP address, which is required for the web service to reach the database
services block Provisions a Python web service with:
  • Build command: pip install uv && uv sync — installs uv and then uses it to install all dependencies declared in pyproject.toml
  • Start command: uv run uvicorn app.main:app --host 0.0.0.0 --port $PORT — Render injects the $PORT variable automatically; the application binds to it
  • Python version: 3.14, pinned via the PYTHON_VERSION environment variable
DATABASE_URL wiring The fromDatabase directive automatically injects the PostgreSQL connection string from fastapi-db into the DATABASE_URL environment variable of the web service. Render resolves this at deploy time, so there is no need to copy and paste connection strings manually.
The application’s app/database.py constructs its SQLAlchemy URL from individual DATABASE_* variables (DATABASE_HOSTNAME, DATABASE_PORT, DATABASE_USERNAME, DATABASE_PASSWORD, DATABASE_NAME), not from DATABASE_URL. After deployment you will need to supply those individual variables (see step 6 below).

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Deployment steps

1

Push the repository to GitHub

Render deploys from a connected Git repository. Fork the project or push it to a GitHub repository under your own account:
git remote set-url origin https://github.com/YOUR_USERNAME/Social-Media-Backend.git
git push -u origin main
2

Create a Render account

Sign up for a free account at render.com if you do not already have one. No credit card is required for the free tier.
3

Create a new Blueprint deployment

In the Render dashboard, click New in the top navigation bar, then select Blueprint from the dropdown menu.
4

Connect your GitHub repository

Authorize Render to access your GitHub account and select the repository that contains render.yaml. Render will scan the repository root for the Blueprint file.
5

Review and apply the Blueprint

Render detects render.yaml and displays a summary of the resources it will create:
  • 1 PostgreSQL database (fastapi-db)
  • 1 web service (fastapi-tutorial)
Review the list, then click Apply to begin provisioning. Render will build the service and start the database in parallel.
6

Set additional environment variables

The Blueprint wires DATABASE_URL automatically, but the application reads individual DATABASE_* variables. Add the following manually in the Render dashboard under Environment for the fastapi-tutorial service:
VariableExample valueDescription
DATABASE_HOSTNAMEdpg-xxx.oregon-postgres.render.comHostname from the Render database info page
DATABASE_PORT5432PostgreSQL port
DATABASE_USERNAMEfastapi_userDatabase user defined in render.yaml
DATABASE_PASSWORD(from Render DB page)Auto-generated by Render
DATABASE_NAMEfastapi_tutorialDatabase name defined in render.yaml
SECRET_KEYa-long-random-stringUsed to sign JWT tokens
ALGORITHMHS256JWT signing algorithm
ACCESS_TOKEN_EXPIRE_MINUTES60Token lifetime in minutes
You can find the individual database credentials on the Render dashboard under Databases → fastapi-db → Info.
7

Render builds and deploys automatically

After saving the environment variables, Render triggers a new deploy. Monitor progress in the Logs tab of the fastapi-tutorial service. A successful deploy ends with a log line from Uvicorn confirming the server is running.Once deployed, your API is available at the URL shown in the service dashboard (e.g., https://fastapi-tutorial.onrender.com).

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Run database migrations after deployment

The Blueprint does not run Alembic migrations automatically. After the first successful deploy, run the migrations using the Render Shell feature:
  1. In the Render dashboard, open the fastapi-tutorial service.
  2. Click the Shell tab to open an interactive terminal inside the running container.
  3. Run:
alembic upgrade head
This creates all tables (posts, users, votes) in the fastapi_tutorial database.

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Important notes

Free tier limitations: Render’s free PostgreSQL database expires and is deleted after 90 days. Export your data before the expiry date if you need to keep it. The free web service spins down after 15 minutes of inactivity — the first request after a period of no traffic will incur a cold start delay of up to 30 seconds while the service wakes up.
  • DATABASE_URL is automatically injected — the fromDatabase directive in render.yaml wires the full PostgreSQL connection string from fastapi-db into the web service at build time. You do not need to copy it manually.
  • Automatic redeploys — once connected, Render redeploys the service automatically on every push to the configured branch (default: main). Each redeploy runs uv sync to pick up any new dependencies.
  • Zero-downtime deploys — on paid plans, Render performs rolling deploys. On the free plan, there is a brief downtime window during each redeploy.

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