{"id":4209,"date":"2025-04-02T12:35:32","date_gmt":"2025-04-02T10:35:32","guid":{"rendered":"https:\/\/europe.wordcamp.org\/2025\/?post_type=wcb_session&#038;p=4209"},"modified":"2025-06-09T14:59:15","modified_gmt":"2025-06-09T12:59:15","slug":"core-web-vitals-mystery-demystified","status":"publish","type":"wcb_session","link":"https:\/\/europe.wordcamp.org\/2025\/session\/core-web-vitals-mystery-demystified\/","title":{"rendered":"Core Web Vitals Mystery Demystified"},"content":{"rendered":"<p>I am often hired to teach performance to WordPress developers, and every time I see the same problem: good, experienced developers feel unconfident when they face performance issues.  They try to do various things but get no or insignificant improvement. This creates frustration and the stereotype that performance is a black box that only a few \u201cchosen ones\u201d can open.    This is absolutely not true.    What they really lack is a system to follow when identifying performance issues, to be able to solve the exact problems that cause these issues and get significant improvement with the effort they invest.    I am going to present the algorithm that I use every single time I improve Core Web Vitals and explain step by step how to identify the issues that really need to be solved so that other developers can apply it in their daily work.<\/p>\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-wordpress-tv-embed wp-block-embed-wordpress-tv-embed wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe title=\"VideoPress Video Player\" aria-label='VideoPress Video Player' width='500' height='281' src='https:\/\/video.wordpress.com\/embed\/HBKKxzTV?hd=1&amp;cover=1' frameborder='0' allowfullscreen allow='clipboard-write'><\/iframe><script src='https:\/\/v0.wordpress.com\/js\/next\/videopress-iframe.js?m=1739540970'><\/script>\n<\/div><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>I am often hired to teach performance to WordPress developers, and every time I see the same problem: good, experienced developers feel unconfident when they face performance issues. They try to do various things but get no or insignificant improvement. This creates frustration and the stereotype that performance is a black box that only a [&hellip;]<\/p>\n","protected":false},"author":13364672,"featured_media":5376,"template":"","meta":{"jetpack_post_was_ever_published":false,"_wcpt_session_time":1749212100,"_wcpt_session_duration":1800,"_wcpt_session_type":"session","_wcpt_session_slides":"https:\/\/europe.wordcamp.org\/2025\/files\/2025\/06\/Sabrina-Zeidan.pdf","_wcpt_session_video":"https:\/\/wordpress.tv\/2025\/06\/07\/core-web-vitals-mystery-demystified\/","_wcpt_speaker_id":[4105],"footnotes":""},"session_track":[54],"session_category":[47],"class_list":["post-4209","wcb_session","type-wcb_session","status-publish","has-post-thumbnail","hentry","wcb_track-track2","wcb_session_category-session-development"],"jetpack_shortlink":"https:\/\/wp.me\/pfPHvs-15T","jetpack_sharing_enabled":true,"session_date_time":{"date":"June 6, 2025","time":"14:15"},"session_speakers":[{"id":"4105","slug":"sabrina-zeidan","name":"Sabrina Zeidan","link":"https:\/\/europe.wordcamp.org\/2025\/speaker\/sabrina-zeidan\/"}],"session_cats_rendered":"Development","_links":{"self":[{"href":"https:\/\/europe.wordcamp.org\/2025\/wp-json\/wp\/v2\/sessions\/4209","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/europe.wordcamp.org\/2025\/wp-json\/wp\/v2\/sessions"}],"about":[{"href":"https:\/\/europe.wordcamp.org\/2025\/wp-json\/wp\/v2\/types\/wcb_session"}],"version-history":[{"count":2,"href":"https:\/\/europe.wordcamp.org\/2025\/wp-json\/wp\/v2\/sessions\/4209\/revisions"}],"predecessor-version":[{"id":7991,"href":"https:\/\/europe.wordcamp.org\/2025\/wp-json\/wp\/v2\/sessions\/4209\/revisions\/7991"}],"speakers":[{"embeddable":true,"href":"https:\/\/europe.wordcamp.org\/2025\/wp-json\/wp\/v2\/speakers\/4105"}],"author":[{"embeddable":true,"href":"https:\/\/europe.wordcamp.org\/2025\/wp-json\/wporg\/v1\/users\/sabrinazeidan"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/europe.wordcamp.org\/2025\/wp-json\/wp\/v2\/media\/5376"}],"wp:attachment":[{"href":"https:\/\/europe.wordcamp.org\/2025\/wp-json\/wp\/v2\/media?parent=4209"}],"wp:term":[{"taxonomy":"wcb_track","embeddable":true,"href":"https:\/\/europe.wordcamp.org\/2025\/wp-json\/wp\/v2\/session_track?post=4209"},{"taxonomy":"wcb_session_category","embeddable":true,"href":"https:\/\/europe.wordcamp.org\/2025\/wp-json\/wp\/v2\/session_category?post=4209"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}