SolidJs vs React: A Comprehensive Comparison

When it comes to building dynamic user interfaces, React has long been a popular choice among developers. However, with the emergence of new frameworks like SolidJs, many are beginning to explore alternatives. In this blog, we'll dive deep into SolidJs vs React.

We will examine their key differences, pros and cons, and how they stack up against each other. Let's begin:

1. Reactivity Model

React

React uses a virtual DOM and a reconciliation process to update the UI. When state changes, React re-renders the entire component, but the virtual DOM helps in minimizing actual DOM updates.

Example:

import React, { useState, useCallback } from 'react';

function Counter() {
  const [count, setCount] = useState(0);

  // useCallback to memoize the increment function
  const increment = useCallback(() => {
    setCount(prevCount => prevCount + 1);
  }, []);

  console.log("Counter component rendered");

  return (
    <div>
      <p>Count: {count}</p>
      <button onClick={increment}>Increment</button>
    </div>
  );
}

function App() {
  return (
    <div>
      <h1>React Counter</h1>
      <Counter />
    </div>
  );
}

export default App;

In this React example:

• We use the useState hook to manage the counter state.
• The entire Counter component re-renders on each state change, as indicated by the console log.
• We use useCallback to memoize the increment function, preventing unnecessary re-creations.

SolidJS

SolidJS employs fine-grained reactivity, updating only the parts of the UI that need to change. This leads to fewer DOM updates and often better performance.

Example:

import { createSignal } from 'solid-js';

function Counter() {
  const [count, setCount] = createSignal(0);

  const increment = () => setCount(count() + 1);

  // This will only run once during initialization
  console.log("Counter component created");

  return (
    <div>
      {/* Only this text node will update when count changes */}
      <p>Count: {count()}</p>
      <button onClick={increment}>Increment</button>
    </div>
  );
}

function App() {
  return (
    <div>
      <h1>SolidJS Counter</h1>
      <Counter />
    </div>
  );
}

export default App;

In this SolidJS example:

• We use createSignal to create a reactive state.
• Only the text node displaying the count will update when the state changes.
• The component itself is not re-rendered, as evidenced by the console log only appearing once.

2. Performance

React

React generally performs well, but performance can degrade in complex applications with frequent state changes.

SolidJS

SolidJS excels in performance due to its fine-grained reactivity model. It often outperforms React in benchmarks, especially in scenarios with intensive UI updates.

Example: To-Do List Application

Let's compare a to-do list implementation in both frameworks to highlight the performance differences:

React Version:

import React, { useState } from 'react';

function TodoItem({ todo, toggleComplete }) {
  console.log(`Rendering TodoItem: ${todo.text}`);
  return (
    <li>
      <input
        type="checkbox"
        checked={todo.completed}
        onChange={() => toggleComplete(todo.id)}
      />
      {todo.text}
    </li>
  );
}

function TodoList() {
  const [todos, setTodos] = useState([
    { id: 1, text: 'Learn React', completed: false },
    { id: 2, text: 'Build an app', completed: false },
  ]);

  const toggleComplete = (id) => {
    setTodos(todos.map(todo =>
      todo.id === id ? { ...todo, completed: !todo.completed } : todo
    ));
  };

  console.log('Rendering TodoList');

  return (
    <ul>
      {todos.map(todo => (
        <TodoItem key={todo.id} todo={todo} toggleComplete={toggleComplete} />
      ))}
    </ul>
  );
}

export default TodoList;

In this React example:

• The entire TodoList component re-renders when any todo item is toggled.
• Each TodoItem also re-renders, even if its state hasn't changed.

SolidJS Version:

import { createSignal, For } from 'solid-js';

function TodoItem(props) {
  const [completed, setCompleted] = createSignal(props.todo.completed);

  console.log(`Creating TodoItem: ${props.todo.text}`);

  return (
    <li>
      <input
        type="checkbox"
        checked={completed()}
        onChange={() => setCompleted(!completed())}
      />
      {props.todo.text}
    </li>
  );
}

function TodoList() {
  const [todos] = createSignal([
    { id: 1, text: 'Learn SolidJS', completed: false },
    { id: 2, text: 'Build an app', completed: false },
  ]);

  console.log('Creating TodoList');

  return (
    <ul>
      <For each={todos()}>{(todo) => 
        <TodoItem todo={todo} />
      }</For>
    </ul>
  );
}

export default TodoList;

In this SolidJS example:

• The TodoList component is created once and doesn't re-render.
• Each TodoItem manages its own completed state.
• When a todo is toggled, only the specific checkbox updates, without affecting other components.

3. Learning Curve

React

• Has a steeper learning curve due to concepts like the virtual DOM, hooks, and the overall ecosystem.
• Requires understanding of JSX, component lifecycle, and state management patterns.

SolidJS

• Easier to grasp for those familiar with reactive programming.
• Might take time to adjust if you're coming from a React background, especially understanding the lack of a virtual DOM.

Example: State Management

Let's compare how state is managed in both frameworks:

React (using hooks):

import React, { useState, useEffect } from 'react';

function UserProfile() {
  const [user, setUser] = useState(null);
  const [loading, setLoading] = useState(true);

  useEffect(() => {
    fetchUser().then(data => {
      setUser(data);
      setLoading(false);
    });
  }, []);

  if (loading) return <div>Loading...</div>;

  return (
    <div>
      <h1>{user.name}</h1>
      <p>Email: {user.email}</p>
    </div>
  );
}

SolidJS:

import { createResource, Show } from 'solid-js';

function UserProfile() {
  const [user] = createResource(fetchUser);

  return (
    <Show when={!user.loading} fallback={<div>Loading...</div>}>
      <div>
        <h1>{user().name}</h1>
        <p>Email: {user().email}</p>
      </div>
    </Show>
  );
}

In these examples:

• React uses multiple useState hooks and an useEffect for data fetching.
• SolidJS uses createResource for data fetching and Show for conditional rendering, resulting in more declarative and concise code.

4. Community and Ecosystem

React

• Boasts a large community, extensive documentation, and a vast ecosystem of libraries and tools.
• Widely adopted in industry, with many job opportunities.

SolidJS

• While growing, its community and ecosystem are still smaller compared to React.
• Gaining traction among developers looking for high-performance alternatives.

Example: Routing

Let's compare routing solutions in both ecosystems:

React (using React Router):

import { BrowserRouter, Routes, Route, Link } from 'react-router-dom';

function App() {
  return (
    <BrowserRouter>
      <nav>
        <Link to="/">Home</Link>
        <Link to="/about">About</Link>
      </nav>
      <Routes>
        <Route path="/" element={<Home />} />
        <Route path="/about" element={<About />} />
      </Routes>
    </BrowserRouter>
  );
}

SolidJS (using Solid App Router):

import { Router, Routes, Route, Link } from '@solidjs/router';

function App() {
  return (
    <Router>
      <nav>
        <Link href="/">Home</Link>
        <Link href="/about">About</Link>
      </nav>
      <Routes>
        <Route path="/" component={Home} />
        <Route path="/about" component={About} />
      </Routes>
    </Router>
  );
}

Both examples show similar syntax and structure, demonstrating that SolidJS is developing comparable tools to those in the React ecosystem.

5. Developer Experience

React

• Offers a robust developer experience with a wide array of tools and extensions.
• Has excellent IDE support and a large number of code snippets and examples available online.

SolidJS

• Prioritizes performance and simplicity, which can lead to a more pleasant development experience for those focused on building fast, efficient applications.
• Growing set of developer tools, including the SolidJS DevTools browser extension.

SolidJS vs React: Strengths and Weaknesses

SolidJS

Pros:

1. Exceptional Performance

   • Fine-grained reactivity updates only what's necessary
   • Compiler-based approach eliminates runtime overhead
   • Consistently outperforms React in benchmarks, especially for large datasets

2. Intuitive Reactive Programming Model

   • Signals provide a clear and predictable state management system
   • Fewer surprises and edge cases compared to React's hook system
   • Easier to reason about data flow and component updates

3. Lightweight and Efficient

   • Smaller bundle size, typically 1/3 the size of equivalent React applications
   • Minimal runtime overhead, as components are compiled away
   • Ideal for performance-critical applications or those targeting low-power devices

4. Familiar Syntax for React Developers

   • Uses JSX, making the transition easier for React developers
   • Similar component structure and lifecycle management

Cons:

1. Smaller Community and Ecosystem

   • Fewer third-party libraries and components available
   • Less community-generated content like tutorials and articles
   • May need to build custom solutions more often

2. Limited Tool Support

   • Fewer developer tools compared to React's extensive ecosystem
   • Limited integration with popular IDEs and code editors
   • Fewer testing utilities and established testing patterns

3. Less Mature Documentation

   • Documentation, while improving, is not as comprehensive as React's
   • Fewer real-world examples and best practices available
   • May require more experimentation to solve complex problems

4. Potential Job Market Limitations

   • Fewer job opportunities compared to the abundant React positions
   • May not be suitable for teams that prioritize using widely-adopted technologies

React

Pros:

1. Large and Active Community

   • Vast pool of resources, tutorials, and community support
   • Regular updates and improvements driven by Facebook and the community
   • Easier to find solutions to problems and get help when needed

2. Rich Ecosystem

   • Extensive library of third-party components and tools
   • Well-established patterns for state management, routing, and more
   • Integration with a wide range of other tools and services

3. Industry Standard

   • Widely adopted in the industry, from startups to large enterprises
   • Abundant job opportunities and career growth potential
   • Well-understood best practices and architectural patterns

4. Flexible and Powerful

   • Can be used for web, mobile (React Native), and desktop applications
   • Supports both declarative and imperative programming styles
   • Suitable for small to large-scale applications

Cons:

1. Performance Overhead

   • Virtual DOM reconciliation can be slower for complex, frequently updating UIs
   • May require careful optimization for peak performance
   • Generally slower than SolidJS in benchmarks, especially for large lists

2. Steeper Learning Curve

   • Concepts like JSX, Virtual DOM, and hooks can be challenging for beginners
   • Best practices evolve frequently, requiring developers to stay updated
   • Managing component lifecycles and side effects can be complex

3. More Boilerplate Code

   • Often requires more code to achieve the same functionality as SolidJS
   • State management in large applications can become verbose
   • Hooks can lead to repetitive code patterns

4. Potential for Runtime Errors

   • Issues like stale closures and incorrect hook usage can cause subtle bugs
   • Some errors only manifest at runtime, making them harder to catch during development

5. Frequent API Changes

   • Regular updates can lead to deprecations and breaking changes
   • Keeping up with best practices and new features can be time-consuming
   • Migrating large codebases to new React versions can be challenging

Quick Decision Checklist: SolidJS or React?

To help you decide whether to choose SolidJS or React for your next project, here's a quick checklist based on the factors discussed:

1. Performance:

   • Need high performance for complex, interactive UIs? → SolidJS
   • Sufficient with good performance and a more general-purpose solution? → React

2. Learning Curve:

   • Comfortable with fine-grained reactivity and simpler concepts? → SolidJS
   • Prefer the extensive ecosystem and don't mind the steeper learning curve? → React

3. Ecosystem and Community:

   • Need a large community and a mature ecosystem with many libraries? → React
   • Okay with a smaller community and growing ecosystem? → SolidJS

4. Developer Experience:

   • Value simplicity and minimalistic code? → SolidJS
   • Prefer rich tooling, extensions, and extensive documentation? → React

5. Project Size:

   • Building a small to medium-sized application? → SolidJS
   • Building a large-scale application with complex state management? → React

6. Tooling and Debugging:

   • Need specialized debugging tools? → React
   • Can work with lightweight, custom tooling? → SolidJS

7. State Management:

   • Need straightforward and reactive state management? → SolidJS
   • Require advanced state management solutions like Redux? → React

By using this checklist, you can make a more informed decision tailored to your project's requirements and your team's familiarity with these frameworks.

Conclusion

In the SolidJs vs React debate, the choice ultimately depends on your specific needs. If you're building a complex application where performance is critical, SolidJs might be the better option. However, if you need a mature ecosystem with a large community, React is still a solid choice.

As always, for more information and resources, you can check out the official documentation for SolidJS. We hope this blog gave you insights to easily make the SolidJS vs React choice!