WordPress.org

Bio

Christoph is a WordPress and PHP specialist, with over 25 years of experience in web development. He started first web projects in the late 90s, some of which are still leading in their field. As technical lead on multiple projects with millions page impressions per month, his responsibilities included theme and plugin development, performance optimizations, and feature planning.

Christoph is a contributor to the WordPress ecosystem, host and founder of his local WordPress Meetup in Dortmund, and a frequent speaker at meetups and WordCamps.

Interests

WordPress, PHP, 3D Printing, DIY

WordPress Origin Story

I started of doing mostly TYPO3 when my good friend Hendrik Luehrsen @luehrsen talked in the highest tones about WordPress. Later during my agency days, I started working with WordPress, and in 2012 I attended my first WordCamp in Berlin, which was called WPCamp. On my second WordCamp in 2013, I met Robert Windisch @nullbyte, well and for everyone who knows Robert, this is all you need to know. Since that day, I’ve only missed a 3 WordCamps in Germany, I became founder and host of my local WordPress Meetup and I’m part of the “usual suspects” to buy a WordCamp ticket on release day.

Since 2014 I call myself an in-house developer for WordPress, doing WordPress as a full-time job. During these days I’ve dug very deep into multiple areas of the WordPress code, found a few bugs, suggested some improvements and the best is yet to come.

Contributions Sponsored

Coding Pioneers GmbH sponsors Christoph Daum to contribute 4 hours per week to the following teams: Community and Core.

Member Since: November 6th, 2011
Location: Germany, Bergkamen
Website: christoph-daum.de
GitHub: apermo
Job Title: Senior Software Developer
Employer: Coding Pioneers
Find me on:

Contribution History

Core Contributor
Documentation Contributor
Meetup Organizer
Plugin Developer
Translation Contributor
Translation Editor
WordCamp Speaker

Mentioned in [61789] on WordPress SVN:
Code Quality: Normalize `object` as type being supplied as comment, post, site, term, and user.
2 days ago
Mentioned in [61778] on WordPress SVN:
Docs: Correct `@see` tag syntax for `@param` descriptions in the Recovery Mode services.
3 days ago
Mentioned in [61773] on WordPress SVN:
REST API: Guard against passing `null` as `$prepared_args` to `WP_REST_Posts_Controller::prepare_items_query()`.
5 days ago
Mentioned in [61768] on WordPress SVN:
Code Quality: Replace `void` with `null` in union return types in `general-template.php`.
5 days ago
Mentioned in [61767] on WordPress SVN:
Code Quality: Replace `void` with `null` in union return types in Customizer classes.
5 days ago
Mentioned in [61766] on WordPress SVN:
Code Quality: Replace `void` with `null` in union return types in `link-template.php`.
5 days ago
Confirmed as a speaker for WordCamp Vienna 2026
7 days ago
Mentioned in [61739] on WordPress SVN:
Docs: Correct parameter variable name in `WP_REST_Icons_Controller`.
1 week ago
Submitted pull request #11016 to WordPress/wordpress-develop:
fix: Fixes the broken caching issue in get_blog_details()
1 week ago
Submitted pull request #11012 to WordPress/wordpress-develop:
Docs: Replace void with null in union return types in various core...
1 week ago
Submitted pull request #11009 to WordPress/wordpress-develop:
Docs: Replace void with null in union return types in class-wpdb.php
1 week ago
Submitted pull request #11008 to WordPress/wordpress-develop:
Docs: Replace void with null in union return types in Administration
1 week ago
Submitted pull request #11006 to WordPress/wordpress-develop:
Docs: Replace void with null in union return types in Customize
1 week ago
Submitted pull request #11005 to WordPress/wordpress-develop:
Docs: Replace void with null in union return types in general-template.php
1 week ago
Created ticket #64704 on Core Trac:
Code Modernization: Replace void in PHPDoc union return types with ...
1 week ago
Submitted pull request #11004 to WordPress/wordpress-develop:
Docs: Replace void with null in union return types in link-template.php
1 week ago
Created ticket #64703 on Core Trac:
Code Modernization: Replace void in PHPDoc union return types with ...
1 week ago
Created ticket #64702 on Core Trac:
Code Modernization: Replace void in PHPDoc union return types with ...
1 week ago
Created ticket #64701 on Core Trac:
Code Modernization: Replace void in PHPDoc union return types with ...
1 week ago
Created ticket #64700 on Core Trac:
Code Modernization: Replace void in PHPDoc union return types with ...
1 week ago
Created ticket #64699 on Core Trac:
Code Modernization: Replace void in PHPDoc union return types with ...
1 week ago
Mentioned in [61719] on WordPress SVN:
Code Quality: Return `null` instead of `void` in `paginate_links()`.
1 week ago
Submitted pull request #10999 to WordPress/wordpress-develop:
General: Return null instead of void in paginate_links()
1 week ago
Created ticket #64694 on Core Trac:
paginate_links(): @return uses void instead of null in union type
1 week ago
Mentioned in [61658] on WordPress SVN:
Menus: Prevent error in Menu location checkbox settings.
2 weeks ago
Mentioned in [61649] on WordPress SVN:
Docs: Add missing `null` to `$post` parameter types in various functions.
2 weeks ago
Submitted pull request #10938 to WordPress/wordpress-develop:
docs: add missing null to $post param types
2 weeks ago
Created ticket #64645 on Core Trac:
Docs: Add missing null to $post parameter types in PHPDoc
2 weeks ago
Mentioned in [61441] on WordPress SVN:
Twenty Sixteen: Ensure the Quote block inherits group color settings.
2 months ago
Mentioned in [61311] on WordPress SVN:
Filesystem API: Check for the correct result in some `WP_Filesystem_FTPext` methods.
3 months ago
Mentioned in [60791] on WordPress SVN:
Docs: Clarify documentation for the `template_redirect` hook.
5 months ago
Submitted pull request #9991 to WordPress/wordpress-develop:
64018: Clarify documentation for the action hook before template determination
5 months ago
Created ticket #64018 on Core Trac:
Improve PHPDoc for template_redirect hook
5 months ago
Mentioned in [60777] on WordPress SVN:
External Libraries: Adopt standard `get_temp_dir()` in `Text_Diff::_getTempDir()`.
6 months ago
Created issue #216 in the wp-cli/media-command repository:
Allow multiple image_sizes for regeneration
8 months ago
Created issue #117 in the wp-cli/cron-command repository:
Add --network flag for event run
8 months ago
Confirmed as a speaker for WordCamp Netherlands 2024
9 months ago
Created ticket #63518 on Core Trac:
get_blog_details( get_all: false ) not working as expected
9 months ago
Closed ticket #63484 on Core Trac:
Attempt to read property "name" on bool - wp-admin/nav-menus.php :1221
9 months ago
Completed the course Open source basics and WordPress on learn.wordpress.org
9 months ago
Created ticket #63484 on Core Trac:
Attempt to read property "name" on bool - wp-admin/nav-menus.php :1221
9 months ago
Submitted pull request #8827 to WordPress/wordpress-develop:
fix: Fixes the error that getchmod() can cause a fatal error
10 months ago
Created ticket #63474 on Core Trac:
getchmod() can cause Fatal error
10 months ago
Is the 19th person to arrive at WordCamp Leipzig, Germany 2025
10 months ago
Is the 36th person to arrive at WordCamp Vienna 2025
10 months ago
Submitted pull request #8688 to WordPress/wordpress-develop:
refactor(media): Refactor month retrieval and add new function for easier caching
11 months ago
Created ticket #63279 on Core Trac:
Improve `media_library_months_with_files` inside `wp_enqueue_media()`
11 months ago
Mentioned in [60157] on WordPress SVN:
Docs: Correct the type of the `$return` parameter in `embed_handler_html` filter.
11 months ago
Mentioned in [60149] on WordPress SVN:
Docs: Correct the type of the `$return` parameter in `embed_handler_html` filter.
11 months ago
Submitted pull request #8661 to WordPress/wordpress-develop:
63248 - PHPDoc fix for embed_handler_html filter
11 months ago