Vue CLI and Vite setup - Performance & Optimization

Performance: Vue CLI and Vite setup

MEDIUM IMPACT

This affects how fast the development server starts and how quickly the app loads in the browser.

Setting up a Vue project for development with fast reload and build times

Vue

npm create vite@latest my-app -- --template vue
cd my-app
npm run dev

Vite serves source files over native ES modules and only bundles on build, enabling near-instant startup and fast hot module replacement.

📈 Performance Gainstartup under 300ms, reloads only changed modules, reducing blocking and improving LCP

Setting up a Vue project for development with fast reload and build times

Vue

vue create my-app
cd my-app
npm run serve

Vue CLI uses webpack which bundles the entire app before serving, causing slower startup and reload times.

📉 Performance Costblocks rendering for 1-3 seconds on startup, triggers full page reload on changes

Performance Comparison

Pattern	DOM Operations	Reflows	Paint Cost	Verdict
Vue CLI setup	N/A (build tool)	N/A	Higher initial paint delay due to bundled scripts	[X] Bad
Vite setup	N/A (build tool)	N/A	Lower initial paint delay with native modules and fast reload	[OK] Good

Rendering Pipeline

The setup affects the critical rendering path by controlling how fast the browser receives and processes JavaScript modules. Vue CLI bundles delay initial script loading, while Vite streams modules natively.

→Network

→Script Parsing

→Style Calculation

→Layout

→Paint

⚠️ BottleneckNetwork and Script Parsing due to large bundled files in Vue CLI

Core Web Vital Affected

LCP

This affects how fast the development server starts and how quickly the app loads in the browser.

Optimization Tips

1Use Vite for faster development server startup and reload times.

2Avoid full bundling during development to reduce blocking and improve LCP.

3Leverage native ES modules to speed up script parsing and module updates.

Performance Quiz - 3 Questions

Which setup generally provides faster development server startup for Vue projects?

A Vue CLI using webpack bundling

B Both have the same startup speed

C Vite using native ES modules

D Neither affects startup speed

DevTools: Performance

How to check: Open DevTools, go to Performance tab, record page load, and compare script evaluation and time to first contentful paint.

What to look for: Look for shorter scripting and loading times with Vite compared to Vue CLI, indicating faster LCP.