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optimization

How do you optimize build times for large JavaScript projects?

optimization
build-time
caching
esbuild
turborepo
Quick Answer

Optimize builds with: incremental/cached builds (Turborepo, Nx), parallel processing, using faster tools (esbuild, SWC), persistent caching, avoiding unnecessary work (affected only), and proper CI caching. Profile builds to find bottlenecks.

Detailed Explanation

Build Optimization Strategies:

  1. Faster Tools:

    • esbuild: 10-100x faster than webpack
    • SWC: Fast Rust-based transpiler
    • Vite: esbuild for dev
  2. Caching:

    • Turborepo remote caching
    • GitHub Actions cache
    • Build artifact caching
  3. Parallelization:

    • Concurrent builds
    • Thread workers
    • Distributed builds
  4. Incremental:

    • Only build changed
    • Affected detection
    • TypeScript incremental

Code Examples

Build optimization configuration
// Using esbuild for fast builds
import esbuild from 'esbuild';

await esbuild.build({
  entryPoints: ['src/index.ts'],
  bundle: true,
  minify: true,
  sourcemap: true,
  target: 'es2020',
  outdir: 'dist',
  // Fast because:
  // - Written in Go
  // - Parallel processing
  // - Minimal passes
});

// Turbo remote caching
// turbo.json
{
  "remoteCache": {
    "signature": true
  },
  "pipeline": {
    "build": {
      "outputs": ["dist/**"],
      "cache": true
    }
  }
}

// TypeScript incremental compilation
// tsconfig.json
{
  "compilerOptions": {
    "incremental": true,
    "tsBuildInfoFile": ".tsbuildinfo"
  }
}

Resources

esbuild Documentation

docs

Turborepo Caching

docs

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