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Understanding Webpack's Require
How webpack's require function manages modules, and how that knowledge helps you debug a bundle.
Top 10 JavaScript Interview Questions based on Array Polyfills
10 interview questions that ask you to write polyfills for JavaScript array methods.
Add Social Authentication to Remix Run Project | Remix Server
Add Google login to a Remix app that runs on the Remix server, with sessions.
How to fix errors like ReferenceError Window is Not Defined in Remix Powered Web App | JavaScript Frameworks
Why Remix throws ReferenceError: window is not defined, and how to run browser-only code safely.
Add Pagination to Remix Run
Add pagination to a Remix app by keeping the current page in the URL.
Optimising Web Performance for Low-Powered Devices
Detect low-powered devices from CPU, memory and network signals, then ship them a lighter bundle.
Production monitoring and the long tail
Part 8 of 8 on image optimisation: monitor image performance in production so it doesn't regress.
Image CDNs and delivery infrastructure
Part 7 of 8 on image optimisation: deliver images at scale with image CDNs.
Prioritising Critical Images
Part 6 of 8 on image optimisation: load the most important image on the page as early as possible.
Lazy Loading Images
Part 5 of 8 on image optimisation: lazy load images below the fold so they don't compete with critical files.
Responsive Images: srcset, sizes, and picture
Part 4 of 8 on image optimisation: serve the right image size and format with srcset, sizes and picture.
Reducing Image Bytes
Part 3 of 8 on image optimisation: cut the number of images and the bytes the browser downloads.
Measuring Image Performance with Core Web Vitals
Part 2 of 8 on image optimisation: measure image performance with Core Web Vitals before you change anything.
Foundations: Why Image Optimisation Matters & How Browsers Load Images
Part 1 of 8 on image optimisation: why images slow pages down and how browsers load them.
Cars24 Frontend Interview Experience
The frontend interview rounds at Cars24, focused on JavaScript, React, machine coding and performance.
How I got promoted at my job?
The steps that led to a promotion at work, shared from experience.
3,124
Video
How to refactor large codebases?
How to approach refactoring a large codebase.
2,689
Video
Implementing JavaScript Promise Polyfill
Write a polyfill for JavaScript promises from scratch.
2,856
Video
How React SSR Actually Works (Without Frameworks)
Build server-side rendering for React without a framework to see how SSR works.
3,058
Video
What is the significance of the React Fiber architecture?
Why React Fiber matters: it lets React pause, prioritise and resume rendering work.
How to improve job search using Google
Use Google search operators to find job openings that match what you want.
Why people fail at interviews?
Common reasons people fail interviews, such as weak fundamentals or unclear requirements, and how to fix each one.
Zomato Frontend Interview Experience | SDE 2
The SDE 2 frontend interview rounds at Zomato, shared by a devtools.tech user.
Microsoft Frontend Interview Experience
The frontend interview rounds at Microsoft, from the recruiter screen onwards, shared by a devtools.tech user.
Best Code Practices for Real-World Applications - Part 1
Six code practices for real apps, from avoiding stale closures in React to fetching data in parallel.
Guide to Effective Interview Preparation
How to use devtools.tech for structured interview preparation, whether you're interviewing now or not.
Flipkart Frontend Interview Experience | UI Engineer 2
The UI Engineer 2 interview rounds at Flipkart, from machine coding onwards, shared by a devtools.tech user.
Internationalization (i18n) in React
Build a React app that supports many languages and regions without changes to its core logic.
Uber Frontend Interview Experience (SDE-2)
The SDE-2 frontend interview rounds at Uber, from the CodeSignal test onwards, shared by a devtools.tech user.
Blinkit Frontend Interview Experience (SDE 1)
The SDE 1 frontend interview rounds at Blinkit, shared by a devtools.tech user.
Walmart Global Tech Frontend Interview Experience (SDE 3)
The SDE 3 frontend interview rounds at Walmart Global Tech, shared by a devtools.tech user.
Mastering Critical Rendering Path
How the browser turns HTML, CSS and JavaScript into pixels, and how to make that faster.
URLs and Routing - Practical Example
Apply URL and routing decisions to a real-world app and see their effects in practice.
URLs and Routing in Frontend Applications
Why URL design is an architecture decision in frontend apps, and how it shapes routing and caching.
Re-rendering vs Unmount in React
When React re-renders a component and when it unmounts it, through one small code example.