Configuration

OpenCode uses a simple JavaScript configuration file that gives you complete control over your build process.

Configuration File

Create an opencode.config.js file in your project root:

// opencode.config.js
export default {
  // Project info
  name: 'my-app',
  version: '1.0.0',
  
  // Development server
  dev: {
    port: 3000,
    host: 'localhost',
    hot: true,
    open: true
  },
  
  // Build configuration
  build: {
    target: 'es2022',
    outDir: 'dist',
    minify: true,
    sourcemap: true
  },
  
  // Plugins
  plugins: []
}

Dev Server Options

Option	Type	Default	Description
port	number	3000	Development server port
host	string	'localhost'	Server hostname
hot	boolean	true	Enable hot module replacement
open	boolean	false	Open browser on start
https	boolean	false	Enable HTTPS
proxy	object	{}	API proxy configuration

Build Options

Option	Type	Default	Description
target	string	'es2020'	JavaScript target version
outDir	string	'dist'	Output directory
minify	boolean	true	Minify output
sourcemap	boolean	false	Generate sourcemaps
clean	boolean	true	Clean outDir before build

API Proxy

Configure proxy rules for API requests during development:

export default {
  dev: {
    port: 3000,
    proxy: {
      '/api': {
        target: 'http://localhost:8080',
        changeOrigin: true,
        rewrite: (path) => path.replace(/^\/api/, '')
      }
    }
  }
}

Environment Variables

Access environment variables in your config:

export default {
  build: {
    minify: process.env.NODE_ENV === 'production',
    sourcemap: process.env.NODE_ENV !== 'production'
  }
}

Or use a .env file:

# .env
VITE_API_URL=https://api.example.com
VITE_DEBUG=true

TypeScript Configuration

For TypeScript projects, you can use opencode.config.ts:

import { defineConfig } from 'opencode';

export default defineConfig({
  build: {
    target: 'es2022',
    minify: true
  },
  plugins: [
    // TypeScript is included by default
  ]
});

Multiple Configurations

Export different configs for different environments:

import { defineConfig } from 'opencode';

export default defineConfig(({ mode }) => {
  if (mode === 'development') {
    return {
      dev: { port: 3000 },
      build: { sourcemap: true }
    };
  }
  
  return {
    build: {
      minify: true,
      sourcemap: false
    }
  };
});