Build optimization for production in Vue - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ component_behavior

intermediate

How does Vue handle production build optimizations?

When you run a Vue app in production mode, what main optimization does Vue's build process apply to the component templates?

A It disables all component reactivity to improve speed.

B It converts all components into plain HTML files without JavaScript.

C It compiles templates into efficient render functions that avoid runtime template compilation.

D It bundles each component as a separate JavaScript file to load on demand.

💡 Hint

Think about how Vue avoids extra work when rendering templates in production.

Vue's production build compiles templates into render functions ahead of time. This avoids the need to compile templates in the browser, making rendering faster and smaller.

📝 Syntax

intermediate

Which Vue CLI command builds for production?

You want to create an optimized production build of your Vue app using Vue CLI. Which command should you run?

A vue-cli-service test

B vue-cli-service serve

C vue-cli-service dev

D vue-cli-service build

💡 Hint

The command for production build is different from the one that runs a development server.

vue-cli-service build creates a production-ready optimized build. serve runs a dev server, and others are unrelated.

🔧 Debug

advanced

Why does your production build include unused CSS?

You notice your Vue app's production CSS bundle is very large and includes styles not used in your app. What is the most likely cause?

A You did not enable CSS tree-shaking or purge in your build config.

B Vue automatically removes unused CSS, so this is a bug.

C Your components are missing <style scoped> tags, causing CSS duplication.

D You used inline styles instead of external CSS files.

💡 Hint

Think about how unused CSS can be removed during build.

Vue's build tools do not remove unused CSS automatically unless you configure tools like PurgeCSS or enable CSS tree-shaking.

🧠 Conceptual

advanced

What is code splitting in Vue production builds?

In Vue production builds, what does code splitting do?

A It merges all JavaScript into one big file for faster parsing.

B It breaks the app's JavaScript into smaller chunks loaded on demand to improve load speed.

C It removes all comments and whitespace from the code.

D It converts JavaScript code into CSS styles for faster rendering.

💡 Hint

Think about how loading smaller files on demand helps user experience.

Code splitting divides JavaScript into smaller files that load only when needed, reducing initial load time and improving performance.

❓ state_output

expert

What is the size difference after enabling Vue production mode?

You build your Vue app twice: once in development mode and once in production mode. Which statement best describes the size difference of the main JavaScript bundle?

A The production bundle is significantly smaller due to minification, dead code elimination, and template compilation.

B The production bundle is larger because it includes extra debugging info.

C The development bundle is smaller because it skips optimizations.

D Both bundles are the same size because Vue does not change code size between modes.

💡 Hint

Consider what build tools do differently for production.

Production builds use minification, remove unused code, and precompile templates, making bundles smaller and faster.