Product Lead Announcement: Grok will fully take over the recommendation algorithm next week, calling it "the most important change ever made on X."

According to 1M AI News monitoring, X product lead Nikita Bier posted that “Grok will fully take over the algorithm next week, which will be the most significant change we’ve made on X.” Previously, Elon Musk announced on March 20 that X would undergo a major update to its AI recommendation algorithm and would open-source the complete code.

According to disclosed information, the new algorithm, internally codenamed “Phoenix,” is based on the same Transformer architecture as the Grok model under xAI. It replaces the previous rule-based + machine learning hybrid system with end-to-end learning. The retrieval stage uses a dual-tower model to match users with candidate posts, and the ranking stage employs a Transformer to predict interaction probabilities. The code will be released on GitHub on the same day as the launch, with updates every four weeks and developer notes.

Musk previously admitted that the current algorithm is “very dumb and needs significant improvement,” but emphasized, “At least you can see us working on it in real-time—no other social platform dares to do this.” Currently, no other mainstream social platforms (Meta, TikTok, YouTube) have open-sourced their production recommendation algorithms. X partially 공개ed an older version of the code in 2023, but that version was incomplete and has been completely rewritten.

Nikita Bier joined X as product lead in July 2025, after founding two startups and selling products to Facebook and Discord.