Creating a new Vue project - Performance Optimization Steps

Performance: Creating a new Vue project

MEDIUM IMPACT

This affects the initial page load speed and bundle size of the Vue app.

Setting up a new Vue project for fast loading

Vue

npm init vue@latest
# Select minimal features: no router, no state management, no testing
npm install
npm run dev

Reduces bundle size by excluding unused features, speeding up initial load and rendering.

📈 Performance Gainsaves 150kb+ in bundle, reduces LCP by 300-500ms

Setting up a new Vue project for fast loading

Vue

npm init vue@latest
# Choose default options with all plugins and features enabled
npm install
npm run dev

Including all optional plugins and features by default adds unnecessary code and increases bundle size.

📉 Performance Costadds 200kb+ to bundle, blocks rendering longer during initial load

Performance Comparison

Pattern	DOM Operations	Reflows	Paint Cost	Verdict
Default full feature setup	Moderate DOM nodes	Multiple reflows during hydration	High paint cost due to large bundle	[X] Bad
Minimal feature setup	Minimal DOM nodes	Single reflow after hydration	Lower paint cost with smaller bundle	[OK] Good

Rendering Pipeline

Creating a new Vue project sets up the JavaScript bundle and HTML structure that the browser loads and renders. The size and complexity of the generated bundle affect how long the browser spends parsing, compiling, and executing scripts before painting the page.

→Network

→Script Parsing

→Style Calculation

→Layout

→Paint

⚠️ BottleneckScript Parsing and Execution due to large bundle size

Core Web Vital Affected

LCP

This affects the initial page load speed and bundle size of the Vue app.

Optimization Tips

1Choose minimal features during Vue project setup to reduce bundle size.

2Avoid adding unnecessary plugins or dependencies initially.

3Use browser DevTools Network tab to monitor bundle size and load times.

Performance Quiz - 3 Questions

What is a key performance benefit of selecting minimal features when creating a new Vue project?

A Smaller JavaScript bundle size leading to faster page load

B More DOM nodes created for better UI

C Longer script parsing time for better debugging

D Increased CSS complexity for richer styles

DevTools: Network

How to check: Open DevTools > Network tab, reload the page, and observe the size of the main JavaScript bundle file.

What to look for: Look for smaller JS bundle sizes and faster load times indicating better performance.

Practice

1. What is the correct command to start creating a new Vue project using the latest recommended method?

easy

A. npm create vue@latest

B. vue create project

C. npm install vue

D. npm run vue

Solution

1. Step 1: Understand the official Vue project creation command

   The recommended way to create a new Vue project is using npm create vue@latest, which scaffolds the project with the latest setup.

2. Step 2: Compare with other commands

   Other commands either install Vue or run scripts but do not create a new project scaffold.

3. Final Answer:

   npm create vue@latest -> Option A

4. Quick Check:

   Use npm create vue@latest to start a Vue project [OK]

Hint: Use 'npm create vue@latest' to start a new Vue project [OK]

Common Mistakes:

• Using 'vue create' which is from older Vue CLI
• Trying to install Vue instead of creating project
• Running npm scripts unrelated to project creation

2. Which of the following commands correctly runs the development server after creating a Vue project?

easy

A. vue serve

B. npm start

C. npm run dev

D. npm run start

Solution

1. Step 1: Identify the standard Vue dev server command

   After creating a Vue project, the usual command to start the development server is npm run dev.

2. Step 2: Understand why other options are incorrect

   npm start or npm run start are common in other projects but not default in Vue. vue serve is not standard in Vue 3 projects created with the latest tool.

3. Final Answer:

   npm run dev -> Option C

4. Quick Check:

   Run dev server with npm run dev [OK]

Hint: Use 'npm run dev' to start Vue dev server [OK]

Common Mistakes:

• Using 'npm start' which is not default in Vue projects
• Trying 'vue serve' which is outdated
• Confusing 'npm run start' with 'npm run dev'

3. After running npm create vue@latest and answering setup questions, what will happen when you run npm run dev inside the project folder?

medium

A. The Vue app compiles and opens a local server showing the default welcome page.

B. It installs Vue dependencies but does not start any server.

C. It throws an error because the project is not built yet.

D. It deletes the project files and exits.

Solution

1. Step 1: Understand the purpose of 'npm run dev'

   This command starts the development server, compiles the Vue app, and serves it locally.

2. Step 2: Recognize expected behavior after project setup

   After setup, running this command shows the default Vue welcome page in the browser.

3. Final Answer:

   The Vue app compiles and opens a local server showing the default welcome page. -> Option A

4. Quick Check:

   Dev server runs and shows app page [OK]

Hint: Run 'npm run dev' to see your Vue app live locally [OK]

Common Mistakes:

• Expecting 'npm run dev' to only install dependencies
• Thinking the command builds but does not serve
• Confusing errors with missing setup steps

4. You ran npm create vue@latest but got an error saying 'command not found'. What is the most likely cause?

medium

A. You forgot to create a project folder before running the command.

B. You do not have Node.js and npm installed or they are not in your system PATH.

C. You need to run the command inside an existing Vue project folder.

D. The command requires an internet connection but you are offline.

Solution

1. Step 1: Understand the error 'command not found'

   This error usually means the system does not recognize the command because Node.js and npm are missing or not set up properly.

2. Step 2: Evaluate other options

   Creating a folder or internet connection issues do not cause 'command not found'. Running inside a Vue project folder is not required to create a new project.

3. Final Answer:

   You do not have Node.js and npm installed or they are not in your system PATH. -> Option B

4. Quick Check:

   Missing Node.js/npm causes 'command not found' [OK]

Hint: Check Node.js and npm installation if command not found error appears [OK]

Common Mistakes:

• Assuming folder creation is required before command
• Thinking command must run inside Vue project
• Ignoring system PATH setup for Node.js/npm

5. You want to create a Vue project with TypeScript support and router enabled. Which step should you do during npm create vue@latest setup to achieve this?

hard

A. Edit the package.json file after creation to add TypeScript and Router dependencies.

B. Manually install TypeScript and Vue Router after project creation.

C. Run npm create vue@latest --typescript --router to auto-enable features.

D. Select TypeScript and Router options when prompted during the setup questions.

Solution

1. Step 1: Understand the interactive setup process

   When running npm create vue@latest, it asks questions to customize your project, including enabling TypeScript and Router.

2. Step 2: Recognize the correct way to enable features

   Selecting these options during setup automatically configures the project with needed dependencies and settings.

3. Step 3: Evaluate other options

   Manual installs or editing files after creation are possible but not the recommended or easiest way. Command line flags such as npm create vue@latest --typescript --router are not supported.

4. Final Answer:

   Select TypeScript and Router options when prompted during the setup questions. -> Option D

5. Quick Check:

   Choose features during setup for easy config [OK]

Hint: Pick features during setup prompts to configure project easily [OK]

Common Mistakes:

• Trying to add features only after project creation
• Assuming command line flags auto-enable features
• Editing package.json manually instead of using setup