A definitive guide to WordPress block development

Wp block editor book nobg

Dive into the definitive resource for WordPress developers seeking to master the Block Editor (Gutenberg) ecosystem. This comprehensive guide covers everything from extending existing blocks to building custom implementations and enterprise-grade solutions. With practical examples, progressive learning structure, and thorough explanations, this book will transform you into a Block Editor expert.

The WordPress Block Editor has fundamentally transformed how developers and content creators interact with WordPress. What began as a new content editor has evolved into the foundation of the entire WordPress experience, touching everything from post editing to site customization, theme development, and enterprise solutions.

Rather than treating the Block Editor as just another feature, this book approaches blocks as the fundamental building units of the WordPress ecosystem—a perspective that aligns with WordPress’s own direction and future.

Sample Content

Extending and Customizing Core Blocks

Before diving into building custom blocks from scratch, it’s essential to understand how to extend and customize WordPress’s existing core blocks. The Block Editor ecosystem provides powerful mechanisms for modifying core block behavior without reinventing the wheel. This approach offers several advantages: faster development cycles, better compatibility with WordPress updates, and leveraging the robust foundation that core blocks provide.

Understanding Core Block Extension Points

WordPress core blocks are designed with extensibility in mind. Rather than being monolithic components, they expose various extension points that allow developers to modify their behavior, appearance, and functionality. These extension points follow WordPress’s philosophy of providing sensible defaults while allowing in-depth customization when needed.

The primary methods for extending core blocks include:

  • Block Variations: Creating alternative versions of existing blocks with different default attributes
  • Block Styles: Adding custom CSS classes and styling options to existing blocks
  • Block Filters: Using WordPress’s filter system to modify block behavior at registration or rendering time
  • Block Supports: Leveraging and extending the built-in support system for features like colors, typography, and spacing
  • Block Transforms: Creating conversion paths between different block types
// Creating a Call to Action variation of the Group block
import { registerBlockVariation } from '@wordpress/blocks';

registerBlockVariation('core/group', {
  name: 'cta-section',
  title: 'Call to Action Section',
  description: 'A pre-styled section designed for conversion-focused content',

  attributes: {
    backgroundColor: 'accent',
    className: 'is-style-cta',
    align: 'wide',
  },

  innerBlocks: [
    ['core/heading', {
      level: 2,
      content: 'Ready to get started?',
      align: 'center'
    }],
    ['core/paragraph', {
      content: 'Join thousands of satisfied customers today.',
      align: 'center'
    }],
    ['core/buttons', {}, [
      ['core/button', {
        text: 'Sign Up Now',
        backgroundColor: 'primary'
      }]
    ]]
  ],

  scope: ['inserter'],
  icon: 'megaphone',
});
Code language: JavaScript (javascript)

About the Author

Paulo Carvajal, web developer.

Paulo Carvajal

Website | LinkedIn | GitHub

Paulo Carvajal is a senior web developer and WordPress specialist with over two decades of experience in front-end development and content management systems. Based in Bilbao, Spain, he has dedicated the past 15 years to advancing custom WordPress solutions, focusing on component-based development.

Paulo started Vudumedia and was its lead developer for twenty years. He made custom websites and apps for clients in different industries by using modern JavaScript frameworks, PHP development, and RESTful API design.

Recently, he has contributed as a senior developer to large-scale projects at leading digital consultancies including Flat 101 and VML-The Cocktail, where his work focused on architecting scalable, maintainable WordPress platforms. This includes headless solutions using technologies such as Vue.js and Next.js, and multisite environments.

Paulo holds a Bachelor’s degree in Fine Arts with a specialization in Audiovisual Media from the University of the Basque Country (UPV/EHU), which informs his design sensibility, attention to accessibility, and user-centered approach in digital environments.

In this book, Paulo shares his practical knowledge and technical insights into building, extending, and optimizing WordPress blocks, providing developers with a thorough and hands-on foundation for working with the modern WordPress architecture.

You can learn more about his work at paulocarvajal.com or connect with him on LinkedIn.

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