Everything You Need to Become an Expert WordPress Developer

Becoming a skilled developer takes time and dedication. The ever-evolving world of frameworks and web technologies means there’s always something new to learn. One of the most popular PHP CMS platforms out there is WordPress, which powers nearly 20% of all self-hosted websites.

If you’re interested in PHP development, mastering WordPress is a must. But how do you go about doing it?

In this post, I’ll walk you through the key areas of WordPress that every developer should master. To make it easier, you can create your own structured WordPress learning plan where you delve into specific areas for a few weeks or months at a time. This approach will help you stay focused and progress through WordPress at an impressive speed.

Discover the Art of Modern WordPress Theming

Before diving into the intricate details, let’s take a moment to familiarize ourselves with the WordPress dashboard if you’re new to this platform.

However, assuming you already have a basic grasp of WordPress, and are seeking to unleash your coding skills to build on its foundation, I’ve got you covered.

In my opinion, theming is where you should start. Sure, plugins are awesome, and custom functions are incredibly handy. But when it comes to WordPress, theming is an absolute must. Whether you’re crafting a theme from scratch or adding your personal touch to an existing one, you need to feel at ease with WordPress’ versatile theming system.

When you’re creating a WordPress theme, you only need two files: style.css and index.php. These are the essentials that make your theme work. There’s a neat trick in WordPress theming – if you don’t have a homepage.php, WordPress will automatically use index.php for the homepage. The same goes for author.php – if it’s missing, WordPress will default to archive.php for the author archive page.

WordPress theming is pretty clever, and it becomes easy to understand once you grasp the hierarchy. Here’s a handy list of the minimum files that every WordPress theme should have:

– style.css: This is the official stylesheet for your theme. It contains important information about your theme.

– index.php: This is the fallback page for anything that doesn’t have a specific theme file.

– home.php: This file is responsible for displaying your blog’s homepage, whether it’s static or archive content.

Let’s talk about different types of layouts you can use for your website. There are several template files that you can work with in WordPress, each serving a specific purpose.

First, we have the “single.php” file. This template is used for displaying a single post or article. So, whenever you click on a post or article on your website, the content will be shown using this layout.

Next, we have the “page.php” file. This template is used for displaying a single page on your website. It provides a consistent layout for all the pages on your site.

Then we have the “archive.php” file. This template is like a catch-all for different types of archives. It can be used for categories, tags, authors, and dates. So, if you want to display a collection of posts or articles from a certain category or tag, this layout will be used.

Lastly, we have the “404.php” file. This is the default error page layout that is shown when a page is not found on your website. It provides a simple and informative layout to let your visitors know that the page they are looking for does not exist.

It’s worth mentioning that advanced themes may include more specific files to help define better content and page layout designs. This allows you to customize your website even further.

If you want to learn more about these template files and how they work, you can check out the template files list in WordPress’ official documentation. They also provide a handy diagram explaining how theme file hierarchies operate.

So, now you have a better understanding of the different types of layouts you can use for your website. Explore these options and get creative with your design!

When it comes to building a website, each theme is like its own unique package. Think of it as a standalone entity that comes with its own special features and tools. These themes are written in PHP, which allows for the inclusion of a theme file that acts like a library of functions. This way, you can limit certain features to just one theme.

But there’s another option called child theming, which can be a great way to build on top of an existing theme. It’s a bit more advanced, though, and not everyone is a fan because it can get pretty complex.

Personally, I believe it’s worth understanding how child themes work so you can decide if they’re right for your project. They might just be the perfect fit!

Getting Started with Plugins

When it comes to WordPress development, there are two major areas to focus on: themes and plugins. Themes control the look and feel of your website, so it’s best to start there. Once you have a good grasp of themes, you can move on to plugin development.

Creating a WordPress plugin may seem challenging at first, but with practice, it becomes much easier. Thankfully, there are plenty of online resources available to help you learn and master plugin development.

It’s important to mention that there is a vast collection of free plugins that you can use to build your WordPress website without ever having to write your own code. However, as a skilled WordPress developer, it’s beneficial to have an understanding of how plugins work and how to create one if the need arises.

Two really important terms you need to understand are filters and actions. They both take some code and give back something, but they do it in different ways.

Filters are meant to give back code, like a string of HTML or an updated variable. Actions give back code directly into predefined hooks found in WordPress themes, plugins, or even in the WordPress core.

Take a look at this Stack thread to learn more.

These different ways of doing things have functions that are similar to each other. For example, add_action() and add_filter() act similarly for actions and filters, respectively. The same goes for do_action() and apply_filters().

Creating plugins involves a lot of reading and practice. You’ll feel confused at times, but that’s just part of the learning process.

I highly recommend checking out this Tuts+ guide that covers the basics of actions and filters. WP Engineer also has a fantastic post on creating your own hooks, which goes deeper into building themes and plugins with extendable code.

Now, let’s talk about the internal features you can develop in WordPress. There are several classes and APIs that are available to all developers, offering different functionalities. Some of these features, like the rewrite API or the REST API, are more advanced. However, if you’re new to development, it’s a good idea to start with the basics.

One of the essential files in WordPress is the functions.php file. People have different opinions about it, but personally, I’m a big fan. This file stores theme-specific functions and settings that define how the theme works using shortcodes, hooks, and filters.

In my theme’s functions file, I can create custom PHP functions that I can use in other theme files. Some people think this is not a good idea, but it’s actually the best way to keep all the theme-specific functions organized in one place.

If you want to see some examples of what you can do with a theme’s functions.php file, you should check out this list of free code snippets.

Another cool feature that you can use in WordPress is shortcodes. A shortcode is a piece of PHP code that you can directly add to your content. It’s usually represented by square brackets in the WordPress editor, like

If you want to learn more about shortcodes and see some examples, you should take a look at the shortcodes documentation.

Lastly, I want to mention custom post types. This feature allows you to create different types of content that go beyond just blog posts and pages. You can define your own custom post types and give them unique attributes and behaviors.

I hope this gives you a better understanding of some of the advanced features you can use in your WordPress theme!

Before WordPress 3.0, there were only a few types of posts available by default: attachments, posts, and pages. These are usually more than enough and they work well for most WordPress websites.

However, with the introduction of Custom Post Types (CPTs), developers have the ability to create new types of posts, such as newsletters, eCommerce products, and user-submitted content.

What’s great is that these custom post types can have their own unique taxonomies, in addition to the default tags and categories. You can define CPTs either with a plugin or by adding code to your theme’s functions.php file. Once you understand how they work and learn how to create your own, you’ll have a lot of flexibility.

Custom Fields

Many developers don’t realize the full potential of custom fields until they start using them. When you write a new post in the admin panel, you’ll see different options for adding tags, categories, and a featured image.

Have you ever wanted to add extra content to your website? Well, with custom fields, you can do just that! These special fields allow you to add more widgets and information to your pages, giving them an extra boost of usefulness.

One popular plugin that makes use of custom fields is Yoast, a fantastic SEO tool. They use custom fields to update the title and meta content on your posts and pages, giving you even more control over your website’s SEO.

But custom fields aren’t limited to just SEO. In fact, you can use them to store all sorts of useful information. Want to have multiple featured images? No problem! Need alternate author bios? You got it! The possibilities are endless once you learn how to create and use custom fields.

Take Your WordPress Skills to the Next Level

I’ve covered a lot of ground in this article, and mastering everything might take some time. WordPress is easy to start with, but becoming a true expert takes practice and dedication. However, with custom fields in your arsenal, you’ll be one step closer to becoming a WordPress master!

When diving into theme/plugin development, it’s worth exploring specific WordPress APIs to broaden your understanding of all that WordPress has to offer.

Here are a few suggestions to help you get started:

1. Settings API: This handy API allows you to create custom settings pages and input fields, giving you greater control over the configuration of your WordPress site.

2. Options API: The Options API is the go-to method for storing database content. With this API, you can easily save and retrieve data, making it an essential tool for developers.

3. Rewrite API: Want to give your WordPress site a unique touch? The Rewrite API lets you rewrite URLs and create custom permalinks, allowing you to tailor your site’s structure to your liking.

4. Transients API: If you need to store temporary data in a database cache, the Transients API is the way to go. It helps you efficiently manage and retrieve temporary data, improving the performance of your site.

5. WP_Query: Sometimes, you need to write custom database queries to fetch specific information from your WordPress database. WP_Query offers a class that simplifies the process, allowing you to create custom queries with ease.

6. Walker: Managing tree data structures, like page hierarchies, can be challenging. Thankfully, the Walker class comes to the rescue. This class helps you navigate and manipulate tree structures in a straightforward manner.

By exploring these APIs, you can take your WordPress development skills to the next level, empowering you to create more powerful and customized themes and plugins. Good luck!

Don’t forget that learning is an ongoing journey. If you want to become a talented developer, all you need is dedication and a love for what you do.

By keeping these subjects handy and practicing regularly, I promise you’ll gain a wealth of knowledge and join the league of accomplished WordPress developers.