# Build Caching in Nano-Remix

The nano-remix package now includes intelligent build caching to improve performance by avoiding unnecessary rebuilds.

## How it Works

The caching system tracks:

- File modification timestamps
- Last build times
- Output file existence

Routes are only rebuilt when:

1. Source files have been modified since last build
2. Output files don't exist
3. Cache is explicitly disabled or forced

## Usage Examples

### Development Mode (with caching)

```typescript
import { nanoRemix } from "@workshop/nano-remix"

// Default behavior - uses intelligent caching
export default {
  fetch: (req: Request) => nanoRemix(req),
}
```

### Development Mode (without caching)

```typescript
import { nanoRemix } from "@workshop/nano-remix"

// Disable caching for development if you want immediate rebuilds
export default {
  fetch: (req: Request) =>
    nanoRemix(req, {
      disableCache: true,
    }),
}
```

### Production Setup

```typescript
import { nanoRemix, preloadAllRoutes } from "@workshop/nano-remix"

// Pre-build all routes on startup for production
const server = {
  async fetch(req: Request) {
    return nanoRemix(req)
  },
}

// Build all routes once on server startup
await preloadAllRoutes()

export default server
```

### Cache Management

```typescript
import { clearBuildCache, getBuildCacheStats } from "@workshop/nano-remix"

// Clear cache (useful for development)
clearBuildCache()

// Get cache statistics for monitoring
const stats = getBuildCacheStats()
console.log("Cache entries:", stats.length)
```

## Configuration Options

```typescript
type Options = {
  routesDir?: string // Custom routes directory
  distDir?: string // Custom output directory
  disableCache?: boolean // Disable caching entirely
}
```

## Performance Impact

With caching enabled:

- ✅ First request to a route: Normal build time
- ✅ Subsequent requests: Near-instant response (no rebuild)
- ✅ File changes: Automatic rebuild on next request
- ✅ Production: Pre-build all routes once

This should significantly improve your server performance, especially for routes that haven't changed!