Frontend Performance Roadmap

Step by step guide to becoming an Android developer.

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Propose
Alternatives
Options

1HTML

Minified HTML – remove comments and whitespaces.
Pre-load URLs where possible.
Minimize number of iframes.

2CSS

Minified CSS – remove comments, whitespaces, etc.
Concatenate CSS into a single file.
Make CSS files non-blocking.
Inline the critical CSS (above-the-fold).
Avoid embedded / inline CSS.
Analyse stylesheet complexity.

3Fonts

Use WOFF2 font format.
Use preconnect to load fonts faster.
Prevent Flash of Invisible Text (FOIT).

4Images

Choose image formats appropriately.
Prefer vector images rather than bitmap.
Avoid using Base64 images.
Load offscreen images lazily.
Serve images close to display size.

5JavaScript

Minify your JavaScript.
Avoid multiple inline <script> snippets.
Non-blocking JavaScript: use async / defer.
Keep dependencies up to date.
Monitor dependency size.
Check performance issues in JS files.
Use Service Workers for caching & heavy tasks.

6Networking & Delivery

Use CDN for assets.
Keep page weight < 1500 KB (ideally < 500 KB).
Keep page load time < 3 seconds.
Keep Time To First Byte (TTFB) < 1.3 seconds.
Minimize HTTP requests.
Serve files from the same protocol.
Avoid unreachable requests (404).
Set proper HTTP cache headers.
Enable GZIP / Brotli compression.

7Cookies

Cookie size < 4096 bytes.
Cookie count < 20.

8Performance Tools

Lighthouse.
WebPageTest.
Chrome DevTools.
Bundlephobia.
Squoosh.app (image optimization).

9Resources

Framework-specific guides.
Recommended talks / guides.
Related Roadmaps