Product Manager Announcement: Grok to Fully Take Over Recommendation Algorithm Next Week, Described as the "Most Significant Change Ever Made on X"

According to 1M AI News monitoring, X Product Lead Nikita Bier posted stating, "Grok will fully take over the algorithm next week, which will be the most significant change we have made on X." Previously, on March 20, Elon Musk had teased that X would undergo a major update to its AI recommendation algorithm and simultaneously open-source the full code.

Per disclosed information, the new algorithm, internally codenamed "Phoenix," is based on the same Transformer architecture as xAI's Grok model, replacing the previous rule-based + machine learning hybrid system with end-to-end learning. During the retrieval phase, a dual-tower model matches users to candidate posts, and during the ranking phase, a Transformer predicts interaction probability. The code will be released on GitHub on the same day as the update, with subsequent bi-weekly syncs and developer guidelines.

Musk had previously admitted that the existing algorithm was "very dumb and needs a major upgrade," but emphasized that "at least you can see us working hard to improve in real-time, something no other social platform dares to do." Currently, no other mainstream social platform (Meta, TikTok, YouTube) has open-sourced their production-level recommendation algorithm. X partially disclosed the old version's code in 2023, but that version was incomplete and has since been completely rewritten.

Nikita Bier joined X as Product Lead in July 2025, having previously founded two startups and sold the products to Facebook and Discord, respectively.