Deployment FAQ

Frequently asked questions about building and deploying EreoJS applications.

Which platforms support Bun?

Bun runs on macOS, Linux, and Windows (via WSL). Deployment platforms that support Bun include:

Platform	Support	Notes
Self-hosted (VPS)	Full	Install Bun directly
Docker	Full	Use the oven/bun base image
Fly.io	Full	Dockerfile-based deployment
Railway	Full	Auto-detects Bun projects
Render	Full	Custom build/start commands
Vercel	Partial	Via Edge Functions adapter
Cloudflare	Partial	Via Workers adapter

For platforms that do not natively support Bun, use a Docker container with the official Bun image.

See the Deployment guides for platform-specific instructions.

How do I set up a production environment?

Set the NODE_ENV environment variable to production and configure your secrets:

# Build the application
NODE_ENV=production bun run build

# Start the production server
NODE_ENV=production bun ereo start

Use environment variables for sensitive configuration. EreoJS reads .env.production automatically in production mode:

# .env.production
DATABASE_URL=postgres://user:pass@host:5432/mydb
SESSION_SECRET=your-secret-here

See the Environment Variables guide for details on env file loading order.

Where are static assets served from?

Static assets in the public/ directory are served from the root URL path. After building, bundled assets (JS, CSS) are output to dist/client/:

public/
  favicon.ico          # Served at /favicon.ico
  robots.txt           # Served at /robots.txt
  images/
    logo.png           # Served at /images/logo.png

dist/
  client/              # Built JS/CSS bundles (auto-served)
  server/              # Server bundle

In production, configure your reverse proxy or CDN to serve dist/client/ with long cache headers, since filenames include content hashes.

How do I enable HTTPS?

For local development, EreoJS can generate self-signed certificates:

// ereo.config.ts
export default defineConfig({
  server: {
    https: true, // Auto-generates self-signed cert for localhost
  },
})

In production, terminate HTTPS at your reverse proxy (Nginx, Caddy) or use your platform's built-in HTTPS support (Fly.io, Railway, Vercel all handle this automatically).

How do I configure a custom domain?

Custom domains are configured at the platform level, not in EreoJS itself. Each deployment platform has its own process:

• Fly.io --- fly certs add yourdomain.com
• Railway --- Add domain in the project dashboard
• Vercel --- Add domain in project settings
• Self-hosted --- Configure DNS to point to your server IP and set up HTTPS with Caddy or Nginx

What does the build output directory look like?

Running bun run build produces:

dist/
  client/              # Client-side bundles
    assets/
      index-[hash].js
      index-[hash].css
  server/              # Server-side bundle
    index.js
  static/              # Pre-rendered static pages (SSG routes)
    about.html
    pricing.html

The dist/ directory is self-contained. Deploy it along with node_modules and package.json to run the production server.

To customize the output directory:

// ereo.config.ts
export default defineConfig({
  build: {
    outDir: './build', // Default: './dist'
  },
})

See the Config Reference for all build options.