Vitali Zaidman

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Mocking function calls within a module

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// f.jsexport function b(){
return 'b';
}
export function a(){
return b();
}

The Naive Approach

test('a', () =>…


Sometimes we respond to React element mounts. The first instinct is to useRef & useEffect. But It’s wrong. What you really need is often useCallback.

setRef returned from useCallback


How can you run tests on version X and version Y of a library, with real-world examples of testing React 16 and React 17


React.memo / React.PureComponent usage guide

What’s a Pure Component?


What is issue #14099 in React’s repo and how it affects you?

Why do we need useCallback in the first place?


When working remotely, you benefit much more from good working processes and proactive team members and you are punished much more severely for sloppy work processes and personal carelessness



TypeScript support, Custom hooks tracking (like React-Redux’s useSelector), Tracking of all pure components.

TypeScript Support

Improved Overall Stability

Tracking of all Pure Components


A key concept of React we tend to forget, quickly explained.

How come a React element’s parent might not be the one who renders it?


All you need to know about your role as a developer to improve your website’s position in Google search results.

Vitali Zaidman

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