Title: Debugging for Developers
Author: Destiny Kanno
Published: 11 August 2026

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# Debugging for Developers

   60 mins   Intermediate   development     Updated August 11, 2026

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In this hands-on meetup activity, participants will explore four complementary debugging
tools such as WP_DEBUG, Query Monitor, browser DevTools, and Xdebug to eliminate
guesswork and resolve code issues efficiently. Running primarily within the browser-
based WordPress Playground, attendees will learn how to configure error logs, isolate
database and hook execution data, and catch frontend or block editor JavaScript 
failures. Finally, participants will witness a facilitator-led live demonstration
using the Playground CLI to watch PHP code execute in real-time using Xdebug step-
debugging.

### Learning Objectives

By the end of this activity, participants will be able to:

 * **Configure Safe Debugging Environments:** Set up `WP_DEBUG`, `WP_DEBUG_LOG`,
   and `WP_DEBUG_DISPLAY` within `wp-config.php` to capture runtime activity without
   exposing stack traces to site visitors.
 * **Interpret Core PHP Errors:** Correctly analyze PHP errors, warnings, and notices
   from a generated `debug.log` file to identify the precise file, line, and root
   cause of a fault.
 * **Utilize Query Monitor for Optimization:** Navigate the Query Monitor interface
   to uncover slow database queries, trace mis-ordered hook priority conflicts, 
   and monitor outbound HTTP API failures.
 * **Diagnose Client-Side Script Failures:** Inspect and debug JavaScript errors
   or failed REST API traffic across the front end and the block editor using browser
   DevTools.
 * **Analyze Real-Time Code Execution:** Explain the mechanics of Xdebug breakpoints
   and differentiate the visibility of step-by-step variable evaluation from standard
   log-based debugging.
 * **Evaluate and Select Debugging Tools:** Match specific problem types—such as
   logic bugs, layout crashes, or loading delays—to the most effective debugging
   tool for the job.

## What's included

### Facilitator Guide

Step-by-step instructions for running the session, including timing cues and discussion
prompts.

### Slide Deck

Presentation slides for the full workshop as a PDF, ready to present or print.

## Download this kit

This download includes a facilitator guide and presentation slide deck.

 [  Download kit ](https://learn.wordpress.org/files/2026/08/Debugging-for-Developers.zip)

 Free · No account required · 396 KB