Vite Performance Review Service

Why Vite Performance Matters

Vite promises lightning-fast development and optimised production builds. But performance can degrade due to:

• Configuration issues — Suboptimal Rollup settings or plugin configurations
• Bundle bloat — Poor code splitting shipping unnecessary code
• Dev slowdowns — Excessive pre-bundling or plugin overhead
• Build inefficiency — Missing tree shaking or optimisation opportunities

The review identifies where your Vite setup deviates from optimal patterns.

What We Analyse

Build Configuration

Your vite.config.ts/js significantly impacts performance:

Rollup Options

• Output configuration review
• Manual chunk splitting strategies
• External dependency handling
• Tree shaking configuration

Build Settings

• Target browser configuration
• Minification settings
• Source map generation
• Asset handling

Bundle Analysis

Understanding what ships to production:

Chunk Strategy

• Vendor chunk configuration
• Dynamic import boundaries
• Shared chunk identification
• Loading waterfall analysis

Size Audit

• Per-chunk size breakdown
• Dependency contribution
• Unused code identification
• Compression effectiveness

Plugin Efficiency

Plugins can significantly impact build times:

Plugin Audit

• Transform time per plugin
• Redundant plugin identification
• Configuration optimisation
• Alternative recommendations

Common Plugin Issues

• Babel over-transformation
• Unnecessary polyfills
• Heavy PostCSS processing
• Redundant TypeScript checking

Dev Server Performance

Fast development iteration matters:

Startup Analysis

• Pre-bundling efficiency
• File system caching
• Plugin initialisation
• Module graph building

HMR Performance

• Update propagation speed
• Unnecessary reloads
• Circular dependency impact
• Large module handling

Dependency Handling

Dependencies often cause the biggest issues:

Pre-bundling

• optimizeDeps configuration
• Include/exclude strategies
• Force re-bundling issues
• Cache invalidation

ESM Compatibility

• CommonJS transformation overhead
• Mixed module issues
• Problematic dependencies
• Alternative packages

Common Optimisation Opportunities

Code Splitting Configuration

// vite.config.ts
export default defineConfig({
  build: {
    rollupOptions: {
      output: {
        manualChunks: {
          // Separate vendor chunks by usage pattern
          'react-vendor': ['react', 'react-dom'],
          'ui-vendor': ['@radix-ui/react-dialog', '@radix-ui/react-dropdown-menu'],
          'utils': ['lodash-es', 'date-fns']
        }
      }
    }
  }
})

Dependency Optimisation

export default defineConfig({
  optimizeDeps: {
    // Pre-bundle large dependencies
    include: ['lodash-es', 'axios'],
    // Exclude already ESM-compatible packages
    exclude: ['@vueuse/core']
  }
})

Build Performance

export default defineConfig({
  build: {
    // Target modern browsers for smaller bundles
    target: 'esnext',
    // Reduce minification time in development
    minify: process.env.NODE_ENV === 'production' ? 'esbuild' : false,
    // Analyse bundle composition
    rollupOptions: {
      output: {
        // Consistent chunk naming for caching
        chunkFileNames: 'assets/[name]-[hash].js'
      }
    }
  }
})

Plugin Optimisation

Before: Heavy plugin chain

plugins: [
  react(),
  legacy({ targets: ['ie >= 11'] }), // Adds significant overhead
  visualizer(), // Should only run when needed
]

After: Optimised plugins

plugins: [
  react(),
  // Only add legacy support if actually needed
  ...(needsLegacy ? [legacy({ targets: ['defaults'] })] : []),
  // Only visualize in analysis mode
  ...(process.env.ANALYZE ? [visualizer()] : [])
]

Framework-Specific Guidance

Vite + React

• React Refresh configuration
• Automatic JSX runtime
• Component lazy loading
• Suspense boundaries

Vite + Vue

• Vue plugin optimisation
• Script setup compilation
• Component auto-import efficiency
• Vuex/Pinia code splitting

Vite + Svelte

• Svelte compile options
• Component preprocessing
• Kit-specific optimisations
• Adapter configuration

Vite + Library Mode

• External dependency handling
• Multiple entry points
• Declaration file generation
• CSS extraction strategies

What You’ll Receive

Configuration Audit

• Current configuration analysis
• Suboptimal settings identified
• Recommended configuration changes
• Plugin efficiency report

Bundle Report

• Detailed size breakdown
• Chunk composition analysis
• Dependency impact assessment
• Optimisation opportunities

Implementation Guide

• Prioritised recommendations
• Configuration code examples
• Migration steps if needed
• Measurement methodology

Getting Started

To begin a Vite performance review, provide:

• Repository access or vite.config file
• Current build times and bundle sizes
• Framework being used (React, Vue, etc.)
• Specific performance concerns
• Target browser requirements

A quote will be provided within 24-48 hours based on project scope.