Optimizing JavaScript for Web Performance

In this Hasty Treat, Scott and Wes continue their discussion of website page speed — five more things that make your site slow!

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03:01 - Shipping too much JS

• Code splitting
• Webpack Bundle Analyzer
• Look at dependencies of libraries
• Use fewer libraries

06:38 - Not bundling code

• Build process

08:24 - Not compressing code

• Google Closure Compiler
• Gzip via your server serving assets
• Minify CSS + JS

11:45 - Loading JS asynchronously

• Where should I put tags in HTML markup?
• Solution: Lazy load JS as needed
• Solution: Show HTML first, load JS in the footer
• Solution: Use Async + Defer

16:42 - Missing indexes on DB

• What is a DB index?
• Where should you add them?
• MongoDB Compass

• Syntax 239: Hasty Treat - 5 Things That Make Your Site Slow
• Google PageSpped

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