Building Better React Bundles: Fixing SSR Hydration & Cookie Storage

When constructing modern web applications, developers frequently face two major hurdles: dealing with client-side state in a Server-Side Rendered (SSR) environment, and maintaining small, tree-shakable bundles. In the latest release of react-hook-lab, we address both challenges directly by introducing a robust new useCookie hook and standardizing library exports to keep your builds light and fast.

The Danger of Standard Client-Side Storage

Most basic React implementations for persistent browser storage run into hydration conflicts. Because the server cannot read browser cookies during initial compilation, the pre-rendered HTML often differs from the first client-side render, causing jarring screen flashes and layout shifts. The new useCookie hook uses a strict, safe post-hydration execution path to prevent this behavior entirely.

Code Example 1: Creating Hydration-Safe Cookies

import React from 'react';
import { useCookie } from 'react-hook-lab';

export function UserWelcome() {
  const [userName, setUserName, clearName] = useCookie('user_profile_name', {
    initialValue: 'Guest',
    days: 14,
    path: '/',
  });

  return (
    <div>
      <h1>Welcome back, {userName}!</h1>
      <input 
        type="text" 
        placeholder="Update name..." 
        onChange={(e) => setUserName(e.target.value)} 
      />
      <button onClick={() => clearName()}>Logout</button>
    </div>
  );
}

Orchestrating Global APIs Safely

Another common source of bugs is managing network state safely inside components. Issues such as unmounted state updates, memory leaks, and redundant network calls frequently complicate otherwise simple components. Our refined useResource hook provides unified subscription management and easy testing APIs.

Code Example 2: Loading Dynamic Data with useResource

import React from 'react';
import { useResource } from 'react-hook-lab';

const fetchTask = async (id) => {
  const response = await fetch(`https://jsonplaceholder.typicode.com/todos/${id}`);
  return response.json();
};

export function TaskViewer({ taskId }) {
  const { data, loading, error } = useResource({
    key: `task-item-${taskId}`,
    fetcher: () => fetchTask(taskId),
  });

  if (loading) return <div>Updating task board...</div>;
  if (error) return <div>Failed to load: {error.message}</div>;

  return (
    <div>
      <strong>Task #{taskId}:</strong> {data?.title}
      <span> - {data?.completed ? 'Done' : 'Pending'}</span>
    </div>
  );
}

Cleaner Bundles via Modular Exports

To ensure developers are not penalized for utilizing a comprehensive utility library, we have removed all internal wildcard exports. This strict named-export architecture allows compiler tools like Rollup and Vite to safely eliminate dead code. Only the hooks you actively import will end up in your final application bundle.

Links & Resources

• GitHub: Saurav-TB-Pandey/react-hook-lab
• NPM: react-hook-lab NPM Package
• Developer Profile: Saurav Pandey on LinkedIn