This is extremely incomplete. I’d welcome recommendations for individuals who should be added to this list (and I suppose any who should be removed :)).
Individuals
- Agbonghama, Collins.
- Alexander, Carl
- Writes high quality articles on WP development.
- Awais, Ahmad
- Created popular create-guten-block toolkit, also WPGulp.
- Bahl, Jason.
- Created the popular WPGraphQL plugin.
- Currently works for Gatsby full-time (working on WPGraphQL).
- Balkhi, Syed
- Founder of WPBeginner, OptinMonster, WPForms, IsItWP, RafflePress, and so on. – 3/18/20
- Barron, Brenda
- Prolific author of WP related articles, quality is high.
- Blackbourn, John (johnbillion)
- Currently at Human Made. – 9/26/19.
- Formerly employed by Code For the People and WordPress.com VIP.
- Author of the popular developer tools Query Monitor and User Switching.
- Bueltge, Frank
- WP Core Contributor. – 9/26/19.
- Author of a number of WP plugins including Adminimize, AddQuicktag, and Search & Replace.
- Chan, Lester
- Prolific WP plugin author including WP-DBManager, WP-PageNavi, WP-Polls, WP-PostRatings, WP-PostViews, WP-Print, WP-Sweep, and WP-UserOnline. – 9/26/19.
- Coleman, Jason
- Co-author of Building Web Apps with WordPress 2nd Edition. – 9/26/19.
- Author of Paid Membership Pro plugin.
- Condon, Elliot
- Author of the extremely popular WP plugin Advanced Custom Fields (ACF). – 9/26/19.
- Coyier, Chris
- Founder of CSS Tricks, co-founder of CodePen, co-author of Digging Into WordPress. – 3/18/20.
- Dils, Carrie
- Erickson, Bill
- Popular and long-time author of tutorials on WP, frequent WordCamp speaker, has authored 24 free WP plugins. – 3/18/20.
- Flores, Nile.
- Formerly of Yoast, serial WordCamp speaker, WP blogger.
- Godley, John
- Author of popular WP plugins including Redirection and Search Regex. – 9/26/19.
- Goldman, Jake
- President/Founder of 10up, author of numerous WP plugins, and contributor to WP core. – 9/26/19.
- Haden, Josepha
- Executive Director for WordPress. – 3/18/20.
- Hayes, David
- Prolific writer on WP development at WP Shout! – 9/26/19.
- Hou-Sandi, Helen
- Director of Open Source Initiatives at 10up, WP lead developer. – 3/18/20.
- Hughes, John
- Hulse, Dion.
- Jaquith, Mark
- Member of the WP Core Team. – 9/26/19.
- Author of a number of plugins including Page Links To and Subscribe to Comments.
- Krogsgard, Brian
- Founder and editor of Post Status. – 3/18/20.
- Krol, Karol
- Author of WordPress Complete, currently in its 7th edition. – 9/26/19.
- Lefebvre, Yannick
- Author of WordPress Plugin Development Cookbook. 9/26/19.
- Lema, Chris
- Currently a VP at Liquid Web. Previously with Crowd Favorite, author of popular tutorials, speaker at WordCamps. – 3/18/20.
- Little, Mike
- Co-Founder of WordPress, currently at Human Made. – 9/26/19.
- Losoviz, Leonardo
- Leonardo writes consistently about whats to push WordPress using modern paradigms whether that be serverless, modern PHP, etc.
- McCollin, Rachel
- Author of WordPress 4.0 Site Blueprints (2015), WordPress: Pressing the Limits (2013), WordPress Mobile Web Development Beginner’s Guide (2012), and WordPress Theme Development Beginner’s Guide (2013).
- Also prolific author of high quality WP articles across the web.
- McCue, Ryan
- Currently at Human Made, developer of WP REST API. – 9/26/19.
- McFarlin, Tom
- Messenlehner, Brian
- Co-Founder and President of AppPresser, co-author of Building Web Apps with WordPress. – 9/26/19.
- Meyer, Fred
- Prolific author of WP development articles on WP Shout!
- Mills, Alex (Passed: 2/2019)
- WP Core Contributor, author of a number of popular WordPress plugins (Developer, Regenerate Thumbnails, SyntaxHighlighter Evolved).
- Miyoshi, Takayuki
- WP Core Contributor. – 9/26/19.
- Author of the popular plugins Contact Form 7, Flamingo, and Really Simple CAPTCHA – 9/26/19.
- Mullenweg, Matt
- Co-Founder of WordPress, CEO of Automattic. – 9/26/19.
- Nacin, Andrew
- Currently with the U.S. Digital Service, lead WP developer. – 3/18/20.
- Nimesh, Rakhitha.
- Ozz, Andrew
- One of the lead developers of WordPress. – 9/26/19.
- Author of popular plugins including Classic Editor and TinyMCE Advanced. – 9/26/19.
- Pataki, Daniel
- CTO of Kinsta. – 10/26/19.
- Prolific author of WP development articles, formerly editor of Smashing Magazine’s WP section.
- Author of several plugins including some for ACF.
- Pines, Ben.
- Founder of Elementor.
- Pollock, Josh
- Core Contributor. – 9/26/19.
- Currently with Saturday Drive. – 9/26/19.
- Plugin author (Caldera Forms).
- Written numerous articles on WP.
- Ratnayake, Rakhitha Nimesh
- Author of WordPress Web Application Development, currently in its 3rd edition. – 9/26/19.
- Richard, Ohz
- Co-author of Professional WordPress Plugin Development, WP core contributor. – 9/26/19
- Sabin-Wilson, Lisa
- Author of multiple for Dummies books on WordPress including WordPress, All-in-One, and Web Design. – 9/26/19.
- Savchenko, Andrey “Rarst”
- Longtime WP developer.
- Schlesser, Alain
- Contributor to a number of WP projects including WP Core and WP-CLI.
- Starr, Jeff
- Prolific author of WP plugins including BBQ: Block Bad Queries, Blackhole for Bad Bots, Custom Fields for Gutenberg, Disable Gutenberg, GA Google Analytics, and User Submitted Posts.
- Stathopoulos, Ari
- Best known for his plugin Kirki Customizer Framework he has written several other plugins including WordPress Reset.
- Sternberg, Justin
- Previously worked for WebDevStudios.
- Prolific plugin author including CMB2.
- Tadlock, Justin
- Co-author of Professional WordPress Plugin Development book.
- WP Core Contributor.
- Author of the highly popular Members plugin.
- Create the popular theme framework Theme Hybrid, along with various WP themes.
- Author of numerous plugins including Breadcrumb Trail, Custom Classes, Get the Image. – 9/26/19
- Torbert, Michael
- Author of All in One SEO Pack among other plugins. – 9/23/19.
- Unver, Baris.
- de Valk, Joost
- Founder of Yoast SEO. – 9/26/19
- Williams, Brad
- CEO and Co-Founder of WebDevstudios (WDS).
- Co-author of Professional WordPress: Design and Development and Professional WordPress Plugin Development. – 9/26/19.
- Williamson, Pippin
- Founder of Sandhills Development.
- Author of Easy Digital Downloads.
- Wood, Samuel (“Otto”)
- WP core contributor.
- Authored several plugins including PHP Code Widget and Theme Check.
- Yingling, Jason.
Organizations
- 10up
- Automattic
- Company behind WordPress.com, WooCommerce, Jetpack, Longreads, VaultPress, Akismet, Gravatar, and numerous other software/products.
- Awesome Motive
- Parent company of WPBeginner, WPForms, MonsterInsights, SeedProd, and OptinMonster.
- Beaver Builder
- Elegant Themes
- Creators of the popular Divi Builder.
- Elementor
- Envato
- Runs ThemeForest, CodeCanyon, and Tuts+.
- Human Made
- Created Altis “the next-generation digital experience platform.”
- Created S3-Uploads, Cavalcade, Smart Media, Limit Login Attempts, Asset Manager Framework, React WP Scripts, hm-gutenberg-tools, roles-to-taxonomy, batcache, and so on.
- IncSub
- Parent company of WPMU Dev, CampusPress, and Edublogs.
- Kinsta
- Managed web hosting.
- Modern Tribe
- Authors of The Event Calendar.
- OnTheGoSystems
- Parent company of WPML, ICanLocalize, and WP Types.
- Pagely
- Focused on enterprise services for WP including managed hosting.
- PostStatus
- PressLabs
- Web hosting company focused on WP that has open sourced a number of powerful tools for WordPress, most recently the Presslabs Stack built on Kubernetes.
- Rocketgenius
- Creators of Gravity Forms.
- Sandhills Development
- Creators of Easy Digital Downloads, AffiliateWP, and Restrict Content Pro.
- Themify
- Torque
- UpdraftPlus
- Web Dev Studios
- Creators of Custom Post Types UI, CMB2, Automatic Featured Images for Video, etc.
- Wordfence
- WPBeginner
- WP Engine
- Managed hosting provider, acquired Flywheel (managed hosting), popular Local dev environment.
- WP Mayor
- WP Ninjas
- Creators of Ninja Forms.
- WP Shout
- WP Tavern
- WPMUDEV
- Yoast
Further Study / Partial Bibliography
- 25 Most Successful WordPress Businesses and Companies Today. wpbeginner, 6/2019.